You see only what you know.-- Goethe
The book's sequence follows the traditional order for the introductory pathology course. It was intended to save time for our students, so they would have more time to spend on the most important content of pathology -- understanding why things happen, and why specimens appear as they do.
No matter what your own school is like, the author knows that your faculty wants you to be actively involved in learning. Students are not sponges (to soak up content without thinking) or parrots (to mouth words without understanding). Students are sharks, and it's our job to bloody the waters. Hence this book -- so that you won't ever need to feel lost or helpless, but can get right into the feeding frenzy. Oh by the way, don't get behind in your study of pathology.
Obviously, this book is no substitute for your own hospital or classroom pathologist! The sequence is traditional for a pathology course; hence, there is no table of contents. But notice that this book has an index, which should come in especially handy if you are using it in conjunction with a videodisc guide.
Don't study this too hard. Use it, review it, and enjoy it!
ABOUT THE AUTHOR
In his spare time, he enjoys advising the local chapter of the Lambda Chi Alpha general social fraternity, reading the classics, playing keyboard, singing psalms with the brothers, writing for children, and jumping out of perfectly good airplanes. He has no idea whether he is related to the real Dr. Friedlander, 19th century pathologist Carl who discovered "Friedlander's bacillus".
Comments, suggestions, and corrections for this little book are welcome. So are friendly calls. Phone the author at 816-283-2208.
Edward R. Friedlander, M.D.
Chairman, Dept. of Pathology
University of Health Sciences
1750 Independence Blvd.
Kansas City, Missouri 64124
First Edition -- 1993 Instructions: This will get you on the right track most of the time when you are dealing with biopsy or autopsy microscopic slides.
START:
Tell me, and I forget.
Show me, and I might remember.
Involve me, and I understand.
Consistency
Soft:...Like your earlobe.
Firm:...Like your strongest, leanest muscle when you flex it.
Hard:...Like your knuckle.
Remember the normal consistencies of organs, and that fixed organs are harder than unfixed ones.
Color
Red: ...Fresh blood or fresh myoglobin
Red-orange:...Bilirubin; hemosiderin (sometimes)
Orange:...Carotene
Yellow:...Lipid (adipose tissue; adrenal cortex; most necrosis);
elastic fibers (vessels; yellow ligaments)
Green:...Biliverdin
Blue:...Something non-white seen through a reflective surface
(blood
in your veins through your skin; carbon pigment under the pleura;
blue
iris; cornea in osteogenesis imperfecta).
Purple:... ???
White:...Tumor; granuloma; collagen (fibrous tissue; scar; etc.);
calcium flecks
Gray: ...Lung alveolar tissue
Brown:...Feces; hemosiderin; lipofuscin; melanin; cytochromes (as
in
the liver); formalin-fixed or stale hemoglobin/myoglobin;
debris
Black:...Carbon ("anthracotic pigment"); very abundant melanin;
homogentisic acid ("alkapton"); formalin-fixed hemoglobin turns
dark
brown or black
SELECTED CLASSIC STAINS
Hematoxylin and Eosin: |
Blue : Nucleic acid (DNA, messenger RNA, ribosomes,
transfer
RNA), bacteria, calcium ...Pink : Protein (arginine and lysine)
|
Periodic acid - Schiff (PAS): |
Magenta : Basement membrane, glycogen, mucin, fungus,
cartilage,
alpha-1PI
|
Diastase PAS (dPAS): |
Magenta : Basement membrane, mucin, fungus, cartilage,
alpha-1PI;
NOT glycogen
|
Congo red : |
Brick red with apple green birefringence : All amyloids
|
Trichrome: |
Green or blue : Collagen
|
Reticulin: |
Black : Reticulin fibers
|
Alcian blue: |
Blue : Acid mucopolysaccharide, acid ground substance
|
Mucicarmine: |
Purple-pink : Epithelial mucin
|
Elastic (Verhoeff, van G.): |
Black : Elastic tissue
|
Fontana: |
Black : Melanin
|
Hydrogen peroxide: |
Bleached : Melanin
|
Acid-fast ZN |
Red : Mycobacteria, nocardia, lead inclusions, ceroid
|
Prussian blue: |
Blue : Hemosiderin
|
Rubeanic acid / rhodanine: |
Coppery : Copper
|
Silver: |
Black : Fungi, bacteria, pneumocystis,
argentaffin/argyrophil
(depends on the recipe)
|
Luxol fast blue: |
Blue : Phospholipid (i.e., myelin)
|
Oil Red O: |
Red : Lipid phase, fat, exogenous oils
|
SELECTED IMMUNE STAINS
"Mud"
Alpha-1 antitrypsin (alpha-1AT = alpha-1PI): |
Macrophages and their tumors
|
Alpha-1 antichymotrypsin (à1CT): |
Macrophages and their tumors
|
Carcinoembryonic antigen: |
Adenocarcinomas
|
CD1 (T6): |
Dendritic macrophages ("Langerhans histiocytes") and their tumors
(i.e., "histiocytosis X")
|
Cytokeratin (keratin): |
Almost all epithelial cells and their tumors (adenomas,
papillomas,
carcinomas); myoepithelial cells and their tumors; meningiomas;
embryonal cell carcinomas; mesotheliomas
|
Desmin: |
Smooth, skeletal, and cardiac muscle cells and their tumors
|
Epithelial membrane antigen (EMA): |
Exocrine glands, exocrine adenocarcinomas; renal cell carcinomas;
other
things
|
Factor VIII: |
Endothelial cells and their tumors
|
Glial fibrillary acid protein: |
Glial cells and their tumors; a few others
|
HMB-45: |
Malignant melanomas
|
Leukocyte common antigen (LCA): |
Lymphocytes and malignant lymphomas, other white cells and some
leukemias
|
Neurofilament protein: |
Neurons; neuroblastomas; neuroectodermal cells and their
tumors
|
Neuron specific enolase (NSE): |
Neurons; neuroblastomas; neuroectodermal cells and their
tumors
|
Myoglobin: |
Skeletal and cardiac muscle cells and their tumors
|
OC125 (CA125): |
Serous tumors of the ovary
|
S100: |
Glial cells, Schwann cells, Langerhans histiocytes, Schwann
cells,
melanocytes, chondrocytes, reticulum cells of lymphoid tissue,
myoepithelium, salivary gland cells, sweat gland cells, and most
tumors
derived from any of these.
|
Ulex lectin: |
Endothelial cells and their tumors
|
Vimentin: |
Most mesenchymal cells and most of their tumors, many other
tumors
|
Does it stain blue with hematoxylin? |
Nucleic acid (DNA, messenger RNA, ribosomes, transfer RNA),
bacteria,
or calcium |
Does it stain pink with eosin? |
Arginine & lysine (i.e., protein) |
Does it stain a gaudy magenta color with PAS (periodic acid-
Schiff)? |
Basement membrane, glycogen, mucin, fungus, or cartilage |
Does it lose its PAS-positivity on treatment with diastase
(spit)? |
Glycogen |
Does it stain brick-red with Congo red, and exhibit the
characteristic apple-green birefringence in some direction on
polarized
light examination? |
Amyloid |
Does it stain dark blue or dark green on trichrome (Masson /
Mallory)
stain? |
Collagen |
Does it stain black on reticulin stain, and does it look
like
long black threads? |
Reticulin |
Does it stain purple-pink with the mucicarmine stain? |
Epithelial mucin |
Does it stain blue with alcian blue? |
Acid mucin (i.e., sulfo- or carboxy- mucin), acid ground
substance
NOTE: Exactly how the weakly-acidic mucins like carboxymucin
stain
depends on the recipe used for the stain. |
Does it stain red-brown on immunoperoxidase stain, against a pale
background?
Does it stain bright green (less often, bright red) on
immunofluorescence, against a dark background? |
One specific protein, and you must ask which! |
Is it dense bone where spongy bone should be? Is it excess basement membrane material in a vessel wall? Is it excess basement membrane and/or mesangial matrix in a glomerulus? Is it an area in the brain where the oligodendroglia have been damaged and have been replaced by astrocytes?
Anywhere else in the body, is it just excess dense collagen? |
Sclerosis
|
Is it a very thick basement membrane anywhere except the
bronchial
epithelium? |
Consider late effect of diabetes |
Is it grossly black and obviously gangrenous? Are the cells intact, but with nuclei that are dark, shrivelled ("pyknosis"), and devoid of chromatin texture? Are the cells intact, but with nuclei that have broken up into fragments ("karyorrhexis")?
Are the cells intact, but without nuclei at all ("karyolysis"),
at
least in the business cells (i.e., they are "ghosts")? |
Coagulation necrosis
|
Is it an area of the brain that has softened and melted away
after
trauma or infarction? Is it an area in an organ in which something has softened and melted away, maybe from a bacterial infection and/or the action of neutrophils?
Is it pus? |
Liquefaction necrosis
|
Is it myocardial or skeletal muscle cells crossed transversely by
hypereosinophilic bands?
Is this perhaps: |
Contraction band necrosis |
Is it a portion of heart wall that is thinned but still solid, in
the
distribution of a known artery? Is it a portion of brain that is swollen or absent, in the distribution of a known artery, or in the watershed areas? Is it a discrete, wedge-shaped area with its base on the surface, in the lung (bloody), kidney (pale), liver (blue or pale), or spleen (pale)? Is it a segment of bowel that is dark and engorged with blood?
Is it an area of coagulation necrosis with a sprinkling of
neutrophils
(alive or dead)? |
Infarct
|
Is it yellow and liquid, like pus?
Is it a free cell with a moderate amount of pinkish-staining
cytoplasm, and a segmented live nucleus? |
Neutrophils ("PMN's") |
Is it a free cell with a bilobate nucleus and abundant,
red-
staining granules? |
Eosinophil |
Is it a free cell in a smear, and does it have deep purple-
staining granules concealing an inconspicuous nucleus? |
Basophil |
Is it a free, living cell with a dark-staining, small round
nucleus,
and scanty cytoplasm? |
Lymphocyte (non-proliferating) |
Is it a big, oval, purple free cell with an eccentric nucleus
with
heterochromatin chunks under the nuclear membrane, and a pale
Golgi
spot next to the nucleus? |
Plasma cell |
Is it a free cell about twice the size of an RBC, with a
reticulated
nucleus bearing a dent?
Is it a free cell in connective tissue that you can tell has
eaten
something? |
Monocyte - macrophage |
Is it a cluster of cells with abundant, pink cytoplasm, poorly-
defined cytoplasmic boundaries, and elongated, reticulated,
indented
nuclei, typically lying helter-skelter?
Does it meet the above criteria more or less, and does it contain
a
Langhans or foreign-body giant cell? |
Granuloma
NOTE: The "gestalt" is purple rice-krispies spilled on a frayed
pink
tablecloth. |
Is it neutrophils plus cell debris, and does it appear to
be
liquid? |
Pus |
Is it pus in a confined space, its wall red (gross) and/or
composed of
granulation tissue (micro)?
|
Abscess |
Is it flecks of whitish-yellow dead material all over the
peritoneal
surfaces?
Is it basophilic (i.e., calcium-rich) acellular debris with
identifiable remnants of fat cells? |
Fat necrosis |
Is it obviously-dead, finely-granular, crumbly-looking
material? |
Caseous necrosis |
Is it caseous necrosis with a granuloma?
And do you perhaps have some reason to believe it is
tuberculosis,
histoplasmosis, blastomycosis, or coccidioidomycosis? |
Caseating granuloma |
Is it a granuloma with coagulation necrosis, with other evidence
of
syphilis? |
Gumma |
Is it a bodybuilder's skeletal muscles? Is it the heart muscle of an aerobic athlete, or a patient with systemic hypertension? Is it heart muscle from a patient with aortic stenosis or insufficiency, or mitral insufficiency?
Is it the right ventricle of a patient with longstanding
increased
pulmonary vascular resistance? |
Hypertrophy |
Is it a proliferation of normal-appearing cells, more than
expected in
the normal organ, and the inciting agent makes sense
physiologically? |
Hyperplasia |
Is it wasted muscles from someone with nervous system disease,
undernutrition, or disuse? Is it the adrenal cortex of someone on exogenous steroids, or with anterior pituitary insufficiency?
Is it a brain with wide sulci and deep gyri? |
Atrophy
|
Is it a large airway or endocervix with stratified squamous
epithelium, without bizarre cellular features? Is it bone in a scar? Is it bone in an otherwise-normal cartilage?
Is it some other adult tissue transformed into a different adult
tissue? |
Metaplasia |
Is it an epithelium with bizarre cells, scrambled architecture,
mitotic figures off the basement membrane, and/or failure of
maturation? |
Dysplasia / carcinoma in situ |
Are the business cells of the organ unusually basophilic, with
large,
euchromatin-rich nuclei, and large, round nucleoli? |
Regeneration / repair
|
Is it a V-shaped white depression in the spleen or kidney? Is it a V-shaped scar with its base against the visceral pleura? Is it a sharply-circumscribed, liquified area of brain without inflammation or granulation tissue? Is it a white scar running deep through a portion of myocardium?
Is it patchy fibrosis involving the subendocardial region of the
heart? |
Healed infarct
|
Is it bright red and looks like it really hurts? Are there dilated arteries with lots of neutrophils, especially pavementing neutrophils?
Are there neutrophils in the tissue, outside the blood vessels?
(This
almost always means acute inflammation.) |
Acute inflammation |
Is it a granuloma without any visible necrosis, and no large
foreign
body?
Is there perhaps a strong clinical hint that it is sarcoidosis or
berylliosis or zirconium disease ("armpit sarcoid", etc.)? |
Non-caseating granuloma |
Is it a giant cell with all nuclei located peripherally? |
Langhans giant cell |
Is it a giant cell with nuclei located more or less randomly
throughout the cytoplasm? |
Foreign-body giant cell |
Does it look like a pink star in a clear, round space, inside a
giant
cell? |
Asteroid body |
Is it a calcified, laminated chunk inside a giant cell? |
Schaumann body |
Is it a ball of concentrically-laden collagen, with or without a
caseating center, in a place suspicious for an infectious
granuloma
(i.e., lung, hilar node, spleen, liver?) |
Healed granuloma
|
Is it a mix of pus and granuloma in the lung, with chunks of
stuff that
doesn't look like anything from "Histology"? |
Aspiration pneumonia |
Is it a portion of a normal body surface which has undergone
necrosis
and sloughed, with loss of both epithelium and at least some of
the
underlying connective tissue? Is there now a crater filled with
fibrin
and necrotic debris? |
Ulcer |
Is it a portion of colon that appears to have sticky green
mustard
painted over much of its mucosa?
Is it a portion of colonic mucosa with patchy necrosis of its
upper
half, these areas being covered with tufts of fibrin and
debris? |
Pseudomembranous enterocolitis |
Is it a portion of airway covered with a pseudomembrane?
Is it a yellow heart with fatty change in each myocardial
cell? |
Diphtheria
|
Is it a fibrin meshwork with a few, active-looking spindle cells
entering it? Is it a mix of fibrin and spindle-shaped cells, perhaps with some remaining debris? Is it a mix of spindle-shaped cells and small blood vessels with walls made of simple cuboidal epithelium? Is it edematous tissue with prominent blood vessels and relatively little collagen or other recognizable features?
Is it fairly well-organized connective tissue with less collagen
than
you would expect, and more blood vessels? |
Granulation tissue
|
Is it a nice, clean, neatly-sutured healing wound? |
Healing by primary intention |
Is it a healing wound that isn't nice, clean, and
neatly-sutured? |
Healing by secondary intention |
Is it a large, yellow liver without other pathology? Is it a liver with one or more oil-drops in most of the cells? Is it a tiger-striped heart from a patient with extreme anemia?
Is it a heart that is almost entirely yellow? (Do you perhaps
know the
patient had diphtheria?) |
Fatty change |
Is it clear, needle-shaped spaces, tending to orient
parallel? |
Cholesterol crystals
|
Are they cholesterol crystals within the intima of a blood
vessel?
Is it the intima of an artery with unwholesome-looking yellow
stuff? |
Atherosclerosis NOTE: More about this later!
|
Are they cholesterol crystals free in the lumen of an artery,
with or
without a foreign-body reaction? |
Atheroembolization |
Is it a yellow nodule around the eyes, or on an extensor surface
or
elsewhere?
Is it composed of many foamy macrophages stuck tightly
together? |
Xanthoma
|
Is it fat cells between normal-appearing cardiac muscle
fibers?
Is it real fat in a lymph node, pancreas, or other organ? |
Fatty ingrowth |
Is it liver, and do the nuclei appear to have pale white
centers? |
Glycogenosis of nuclei |
Is it white and crystalline, and in the joint, kidney, or pinna
of a
person with gout? |
Uric acid |
Is it white and crystalline, and in the small pulmonary arteries
and
capillaries? |
IV drug abuser (talc, pill-filler) |
Are they red inclusions in the nuclei of proximal tubular cells,
with a
history suggestive of heavy-metal poisoning? |
Lead / bismuth inclusions
|
Is it a yellow person with kidney failure? |
Urochrome pigment |
Is it a yellow person with hemolysis, liver cell disease, and/or
blocked bile ducts? |
Jaundice |
Is it a yellow person whose palms and soles are the most
yellow? |
Carrot eater ("carotenemia") |
Is it black pigment in the lung, or in a jailhouse tattoo? |
Carbon pigment |
Is it brown pigment at the poles of cardiac nuclei? Is it a tiny, brown heart? Is it brown pigment in a "tortoiseshell colon" (melanosis coli)?
Is it brown pigment in the liver cells in Dubin-Johnson
syndrome? |
Lipofuscin
|
Is it lipofuscin and also acid-fast? |
Ceroid |
Is it brown pigment in the basal layer of the dermis? Is it brown pigment in macrophages, not hemosiderin, in or near with a pigmented skin lesion? Is it a dark-brown or black nodule on the skin? Does it bleach on exposure to hydrogen peroxide?
Does it stain black with the "Fontana" stain for melanin? |
Melanin
|
Is it brown pigment at the site of repetitive trauma, or near a
piece
of shrapnel? Is it a rusty-brown, cirrhotic liver? Is there a history of hemochromatosis or multiple blood transfusions for aplastic anemia? Does it look like barbells in a microscopic view of lung, i.e., is it covering an asbestos fiber?
Does it stain blue (gross or microscopic) with ferrocyanate
("Prussian
Blue")? |
Hemosiderin
|
Is it black cartilage? |
Alkaptonuria / ochronosis |
Is it gray matter in the brain, and is it yellow? |
Kernicterus |
Is it calcified, and is it a scar, caseous necrosis, a dead
worm,
an old granuloma, tissue with scleroderma or a scleroderma
variant, a
deformed cardiac valve, an old blood vessel, an atherosclerotic
plaque,
a Schaumann body, old fat necrosis, old cartilage, pseudogout,
malakoplakia, or a papillary tumor with psammoma bodies? |
Dystrophic calcification
|
Is it calcified, and is it still the normal shape from
"Histology", and is it lung, renal tubular basement
membrane,
gastric fundus basement membrane, or the internal elastic
membrane of a
small blood vessel? |
Metastatic calcification
|
Is it pink-staining, without an internal structure that is
visible on
light microscopy? |
"Hyaline" |
Is it hyaline, and is it a perfect sphere in or near a plasma
cell? |
Russell body |
Is it hyaline, not inflamed, not necrotic, and is it the wall of
an
arteriole? Is there perhaps a history of benign high blood
pressure
and/or diabetes? |
Hyaline arteriolar sclerosis |
Is it hyaline, and is it in the nucleus of a cell, and is it
surrounded by a clear zone? |
Probably a DNA-virus inclusion ("Cowdry A inclusion") |
Is it hyaline, and spherical, and in the cytoplasm of a
non-pigmented
neuron? |
Negri body of rabies |
Is it hyaline, and irregularly shaped, and inside a liver
cell? |
Mallory's alcoholic hyaline |
Is it an extremely hard scar with a smooth, elevated surface?
Is it collagen in a scar that is so densely woven that it appears
hyaline? |
Keloid |
Is it large round masses of hyaline basement-membrane material in
a
glomerulus? |
Nodular diabetic glomerulosclerosis |
Is it amyloid, and does it lose its congophilia on
treatment with
potassium permanganate? |
Amyloid A ("amyloid AA") |
Is it the solid, sealant material that forms the framework of a
scab? Is it a shaggy meshwork of threads, like spider web, at a site of tissue injury? Is it masses of hyaline material, perhaps with cells invading and devouring it, at a site of tissue injury? Is it the crusty stuff on a mat burn or other very superficial abrasion of the skin? Is it masses of hyaline material in granulation tissue? Is it the non-cellular, solid component of a blood clot? Is it "hyaline membranes" lining the small air spaces of injured lung? Is it shaggy stuff hanging off the external surface of the heart?
Is it sticky stuff "loculating" an accumulation of inflammatory
fluid? |
Fibrin
|
Is it shaggy, sticky material binding together two internal
surfaces,
but easily broken with a finger? |
Fibrinous adhesions
|
Is it dense scar or string-like white cords binding together two
internal surfaces, too tough to break with a finger? |
Fibrous adhesions
|
Is it fluid that is visible grossly, but is not apparent
microscopically? Is it an effusion, and the principal diagnosis cirrhosis, congestive heart failure, nephrotic syndrome, or protein malnutrition?
Is it an effusion with a relatively low specific gravity and
protein
content? |
Transudate |
Is it fluid that persists as pink-staining material in a section
after
processing? Is it free fluid from cancer or inflammation?
Is it an effusion with a relatively high specific gravity and
protein
content? |
Exudate |
Is it edema most severe around the ankles? |
Cardiac edema |
Is it edema most severe around the eyes? |
Renal edema |
Is it edema of an extremity or the genitals, often with
roughening of
the skin, after surgery, cancer, or filariasis has obliterated
lymphatic channels? |
Lymphatic obstruction |
Is it a brain with flattened gyri and narrow sulci? |
Cerebral edema |
Is it red blood cells not in a vessel? |
Hemorrhage |
Is it a hemorrhage in the tissues, under 3 mm? |
Petechia |
Is it a hemorrhage in the tissues, over 3 mm? |
Purpura / Ecchymosis |
Is it a hemorrhage in the tissues resulting from trauma? |
Contusion / bruise / ecchymosis |
Is it a palpable mass of blood outside the vessels? |
Hematoma |
Is it a red, throbbing organ? |
Hyperemia |
Is it a blue, non-throbbing, blood-filled organ? Is it a "nutmeg liver"? Has something occluded the venous drainage?
Is the heart unable to pump enough blood out of the organ? |
Congestion
|
Is it an artery with several small lumens instead of one large
one? |
Recanalized thrombus |
Is it a mass of blood with lines of Zahn? |
Ante-mortem thrombus |
Is it blood in a vessel or elsewhere, and it has separated into
one
layer each of "chicken fat" and "current jelly"?
Are all the RBC's on one side of the lumen, with a meniscus? |
Post-mortem thrombus |
Is it a mass of fat, with or without marrow, in a pulmonary or
other
artery?
Is it a brain with lots of petechiae distributed throughout the
white
matter? |
Fat embolus / bone marrow embolus |
Is it a mass of squamous cells in a pulmonary artery? |
Amniotic fluid embolus |
Is it an artery with pink stuff in its media, with abundant
inflammatory cells? |
Probably type III immune injury; if living bacteria are present,
consider mycotic aneurysm |
Is it an artery with pink stuff in its media, with scanty
inflammatory
cells, but with other evidence of recent injury such as necrosis
and/or
intimal swelling? |
Malignant hypertension or radiation injury |
Is it sections of artery, not in the lung, with type III immune
injury
lesions of different ages (acute, chronic, healed)? |
Probably polyarteritis nodosa; rule out lupus, etc. |
Is it an artery with fibrosis and large discontinuities in the
elastica? |
Probably old healed type III immune injury
Less likely: Old healed bacterial vasculitis ("mycotic
aneurysm"), old
trauma |
Is it an artery in the head, throat, ear (any portion), nose,
lung,
kidney, or elsewhere, with evidence of both type III and type IV
injury?
Is it a patient with several of the following: |
Wegener's granulomatosis
NOTE: Miss it and the patient dies. Make the diagnosis and
treatment
is relatively easy and very effective. |
Is it an amyloid spleen with most of the amyloid in the white
pulp? |
Sago spleen |
Is it an amyloid spleen with most of the amyloid in the red
pulp? |
Lardaceous spleen |
Is it a butterfly rash on the face? |
Lupus or dermatomyositis or acne rosacea |
Is it an immunofluorescence photo with green granules along the
basement membrane of the skin? Is it an immunofluorescence photo with all different kinds of green chunks in a glomerulus?
Is there impressive fibrous onion-skinning of the adventitia of
the
splenic arterioles? |
Lupus |
Is it a photomicrograph of muscle, with atrophy of the cells
worst at
the edges of the bundles? Are there purple pads on the knuckles?
Does the patient perhaps have an autoantibody (anti-Jo, etc.)
against a
transfer RNA synthetase? |
Polymyositis / dermatomyositis
|
Are there lymphocytes wrecking havoc on the salivary or lacrimal
glands? |
Sjogren's syndrome |
Is his or her face so stiff that a smile is impossible? Does some other part of the skin look like thick, smooth linoleum? Is the skin smooth and shiny, with telangiectasias? Is it a skin biopsy with thinning of the epidermis, flattening of the dermal-epidermal junction, and very dense collagenization of the dermis, in the absence of a history of exposure to radiation?
Does the patient perhaps have an autoantibody (anti-Scl-70, etc.)
against topoisomerase and/or a nucleolar anti-nuclear antibody
pattern? |
Scleroderma or morphea |
Is there dystrophic calcification of the finger pads? Is the esophagus fibrotic and inflexible along its length?
Are there only a few big blood vessels in the nail bed, instead
of lots
of little ones? |
Scleroderma or CREST
|
Is this a newborn with tetany and immunodeficiency, hypoplastic
or
absent thymus, few or no T-cells, absent parathyroids, and
perhaps also
a cleft palate, a cardiac septal defect, and/or some other
midline
deformity? |
DiGeorge's thymic hypoplasia |
Is it a brain disease with lots of microglial cells and
multinucleate
cells? |
AIDS encephalopathy |
Is it a silver stain of lung, showing silver-positive organisms
in the
alveoli, looking like squashed ping-pong balls? Is it an H&E stain of lung, showing pink froth in the alveoli, and no inflammatory reaction?
Is it a Giemsa stain of lung washings, showing cysts with eight
little
round creatures in them? |
Pneumocystosis |
Is it brown spots from the skin of someone with AIDS or a
transplant?
Is the histopathology something in a range from granulation
tissue to a
vascular spindle-cell sarcoma, but it either |
Kaposi's sarcoma
|
Is it a tumor of small blue cells from an AIDS patient? |
Lymphoma
|
Is it a gross lesion that is round like a ball, and isn't
anywhere in
your "Gross Anatomy" book?
Is it an orderly group of euploid-looking cells, but in a place
or
arrangement not in your "Histology" book? |
Benign tumor (or maybe a choristoma or a hamartoma or a
carcinoid) |
Is it a cauliflower-shaped growth? Is it an ulcer formed by necrosis of a cauliflower-shaped growth? Is the growth (grossly or microscopically) extending tentacles into the surrounding healthy tissue? Are its cells bizarre and/or variably-sized? Is the nuclear-cytoplasmic ratio higher than you would expect for it tissue? Are there lots of mitotic figures where you don't expect them? Are the cells arranged helter-skelter, and it is more than just an intra-epithelial process? Is there a tripolar mitosis, or some other really bizarre mitotic figure? Is it a tumor with hemorrhage and/or necrosis, grossly or microscopically?
Is it a tumor that has metastasized? |
Cancer
|
Is it a benign tumor making glands? |
Adenoma |
Is it a benign tumor composed of a fibrous stalk, like the trunk
of a
tree, surrounded by benign cells, like the leaves of a tree? |
Papilloma (papillary adenoma) |
Is it a cancer with singly keratinized (i.e., orange-staining,
glassy-
looking on H&E) cells? Is it a cancer in which it is easy to see desmosomes (i.e., "prickles") between the cells? Is it a cancer making "pearls" (i.e., poor attempts to make hairs)?
Is it a cancer with cells seen on electron microscopy to be
packed with
tonofilaments? |
Squamous cell carcinoma
|
Is it a cancer making glands? Is it a cancer making inside-out glands (i.e., does it exhibit a papillary growth pattern)? Is it a cancer that stains positive for epithelial mucin (i.e., mucicarmine positive)?
Is it a cancer that stains positive for CEA (carcinoembryonic
antigen)
and/or EMA (epithelial membrane antigen)? |
Adenocarcinoma
NOTE: Biphasic, mixed adenocarcinoma-and-spindle-cell tumor?
Think of
mesothelioma or synovial sarcoma |
Is it a round, apparently well-circumcised tumor, arising where
there
is endoderm, with a white or yellow color on cross-section? In addition to the above, are the cells benign-appearing and uniform, making nests, ribbons, or little gland-like structures? In addition, does it show neurosecretory granules on electron microscopy?
Does the patient perhaps have:
Does the tumor perhaps take the argentaffin and/or argyrophil
silver
stains? |
Carcinoid tumor |
Is it a cancer composed of cells with very scanty cytoplasm? |
"Malignant tumor of small blue cells" / "LEMON tumor"
Consider: |
Is it individual cancer cells invading the epidermis? |
Paget's disease or malignant melanoma NOTE: Paget's disease cells usually stain positive for CEA and/or mucin. Melanoma cells usually show melanin and/or S100 staining.
NOTE: "Paget's disease of bone" / "osteitis deformans" is a
different
entity. |
Is it respiratory epithelium bearing "smudge cells", epithelial
cells
with large, homogenized nuclei? |
Adenovirus pneumonitis |
Is it respiratory epithelium with prominent multinucleated cells
which
are clearly of epithelial origin? |
Respiratory syncytial virus
|
Is it a white Koplik's spot by the duct from the parotid
gland?
Is it a multinucleated giant cell bearing large, herpes-like
intranuclear inclusions? |
Measles
|
Is it skin vesicles, each bearing a central dimple, all of
nearly-
identical age and appearance?
Is it vesicle fluid with cells bearing large intracytoplasmic
inclusions ("Guarneri bodies")? |
Smallpox |
Is it a group of little blisters on the lip, hand, or genitals,
or
along a dermatome? Is it an acute vesicular eruption over most of the skin, with lesions of different ages?
Is it a cell from a necrotizing lesion with one or several pale,
very
swollen nuclei, each bearing a large, eosinophilic intranuclear
inclusion? |
Herpes (simplex / zoster) Varicella ("chickenpox"), shingles, and fever blisters should be familiar to you.
|
Is it a very large cell, with a very large nucleus bearing a
single
very large inclusion? Are there perhaps also many small,
hard-to-see
intracytoplasmic inclusions? |
Cytomegalovirus (CMV) |
Is it liver with little inflammatory infiltrate, and necrosis
primarily in the mid-zonal areas? |
Yellow fever |
Is it a cell from the cornea with many small intracytoplasmic
bodies?
Is it a urethral discharge in a man without gonorrhea or
trichomonas or
a jalape¤o habit? |
Chlamydia |
Is it a tiny bacterium in an endothelial and/or capillary smooth
muscle cell?
Is it a severe vasculitis involving capillaries, with necrosis of
endothelial cells? |
Rickettsial disease
(Organisms also in smooth muscle: RMSF) |
Is it stellate microabscesses with some granuloma formation, in
lymphoid tissue? |
Lymphogranuloma venereum, cat scratch fever, brucellosis, plague, tularemia, glanders, melioidosis, listeria, or yersinia infection |
Is it a blood cell, about 15-25 microns across, with a reticulated
nucleus
and abundant, pale-gray staining, vacuolated cytoplasm? |
Atypical lymphocyte of infectious mononucleosis, etc. (activated
T-
cell, "virocyte") |
Is it large gram-positive cocci in clusters? |
Staphylococci |
Is it large gram-positive cocci in chains? |
Streptococci |
Is it pairs of slightly-elongated, gram-positive cocci, joined at
their poles, usually encapsulated? |
Pneumococci (Streptococcus pneumoniae) |
Is it pairs of small gram-negative cocci, typically inside
neutrophils? |
Neisseria (i.e., gonococci or meningococci) |
Is it tiny bacilli that needed to be stained with silver for
photography? |
Cat scratch fever or Legionnaire's disease |
Is it a mix of various shaped bacteria, mostly gram-negative? |
Anaerobes |
Is it a gram-negative rod attached firmly to the respiratory
mucosa,
but without invasion? |
Whooping cough |
Is it a wiggly-looking, gram-negative rod, seen best on Giemsa or
silver stain, in an "upset stomach" or a gastric or duodenal
ulcer
crater? |
Helicobacter |
Are all of his or her muscles maximally tensed, bent into
opisthotonos, with a "sardonic smile" of lockjaw? |
Tetanus |
Is it a rapidly-spreading, necrotizing process without
inflammation but
with gas formation? Are there large, gram-positive bacilli
here? |
Gas gangrene |
Is it a systemic infection or serious lung infection caused by
gram-
positive bacilli in a person who contacted infected wool?
Is there a blackened eschar where the person contacted wool? |
Anthrax |
Is there an ulcer where the person touched a sick rabbit? |
Tularemia |
Is it a tiny gram-negative coccobacillus in a person with fever
of
unknown origin and a history of exposure to livestock? |
Brucellosis |
Is it a necrotizing, suppurative lymph node infection with
rapidly-
progressing, severe systemic complaints? |
Plague |
Is it an infection by a spiral organism? |
Syphilis, relapsing fever, Helicobacter, Lyme disease, rat-bite
fever
(Spirillum) |
Is it a painless, indurated ulcer on the genitals, mouth, or
anus?
Does the darkfield view perhaps show syphilis spirochetes? |
Chancre of primary syphilis |
Is it a widespread rash that involves the palms and soles? |
Syphilis, RMSF, Kawasaki's mucocutaneous lymph node syndrome,
toxic-
shock / scalded skin syndromes |
Is it a necrotizing lesion centered on the periosteum? Is it a granuloma with a center containing coagulation necrosis and/or with other evidence of tertiary syphilis? Is it demyelinated posterior columns in the absence of cobalamin deficiency? Is it a dilated proximal aorta without severe atherosclerosis, or with a tree-bark intima?
Is it an atrophic brain without evidence of Alzheimer's or other
idiopathic neuro-degenerative disease? Are the meninges perhaps
also
opalescent? |
Tertiary syphilis |
Was it person born with a collapsed nose, or Hutchinson teeth, or
mulberry molars, or a rash on palms and soles, or rhagades? |
Congenital syphilis |
Is it a vasculitis with endothelial cell swelling and a
predominantly
plasmacytic perivascular infiltrate? |
Syphilis, any stage |
Is it a spreading, ring-like erythematous rash, perhaps
relapsing,
around a site of a (remembered or forgotten) tick bite? |
Lyme disease, primary ("erythema chronicum migrans") |
Is this a patient with some or all of the following: ..."arthritis"; ...cranial nerve palsies; ...non-suppurative meningitis; ...encephalitis; ...myocarditis; ...stillbirth? And do the lesions show inflammation with an infiltrate mostly of lymphocytes and (especially) plasma cells? And is serology positive for Lyme disease? And is there perhaps a history of tick bite? |
Lyme disease, secondary / tertiary |
Is it a caseating granuloma without visible organisms on H&E even
if
you look very carefully? Is it caseous necrosis without visible organisms on H&E, especially if there is nothing to suggest Wegener's?
Is it a necrotizing lesion with acid-fast bacilli, especially if
they
appear beaded? |
Tuberculosis |
Does he or she have the typical leonine facies? Does he or she have a neuropathy and/or erythema nodosum, plus an infiltrate of macrophages bearing bacilli?
Is it a plaque on the skin, bearing macrophage-laden bacilli? |
Leprosy NOTE: Pathology varies tremendously depending on how good the person's immune response is. |
Is it weakly acid-fast filamentous bacteria in a lung
infection?
Is it weakly acid-fast bacteria in a mutilating, chronic foot
infection in a poverty victim? |
Nocardiosis |
Is it a colony of "ray fungi", i.e., a sulfur granule, in a
tonsillar
crypt or surrounded by pus? |
Actinomycosis |
Is it pseudohyphae, considerably larger than bacteria, that bud
but do
not branch? Does it look like toy balloon animals?
Is it oral, cutaneous, esophageal, or genital thrush, i.e.,
uncomfortable white patches that scrape off easily? |
Candida |
Is it a mold with 45ø angle branching, septate hyphae, and
perhaps even
a fruiting body?
Is it a brown ball in a lung cavity? |
Aspergillus |
Is it a mold with broad, nonseptate hyphae, branching at 90ø
angles,
typically invading a blood vessel? |
Mucor (Rhizopus, others) |
Is it 2-4 micron yeasts, some perhaps budding, perhaps with shrinkage
artifact creating the illusion of a "capsule", and typically
inside a
living macrophage? |
Histoplasmosis |
Is it a thick-walled, large (maybe 25 micron) yeast with broad-based
single
buds? |
North American blastomycosis |
Is it a large yeast with many buds? |
South American blastomycosis (Para-coccidioidomycosis) |
Is it a 5-10 micron yeast with a large polysaccharide capsule and
perhaps
one narrow-based bud, typically in a very immunosuppressed person
and
with no inflammation? |
Cryptococcus |
Is it a large, dPAS-positive cell in fibrin or an ulcer in the
gut,
often with erythrophagocytosis? Is it flask-shaped ulcers in the colon, with their bases on the muscularis mucosa, with organisms as above? Is it a mass of granulation tissue in the cecum, with organisms as above?
Is it spreading necrosis of the liver, with minimal inflammation,
with
organisms as above? |
Amebiasis
|
Is it a crescent-shaped creature on the brush-border of the
bowel, in a
section?
Is it the familiar "friendly ghost face" in a smear? |
Giardia |
Is it tiny, hematoxyphilic, acid-fast spherules living in the
brush
border of the gut? |
Cryptosporidiosis |
Is it a tumbling, pear-shaped protozoan with flagella and a
fin-like
structure, in a vaginal swab or prostatic fluid? |
Trichomonas |
Is it a parasite in an RBC? |
Malaria or babesiosis |
Is it wavy trypanosomes in the blood?
Is it a trypanosomal disease primarily with an
encephalopathy? |
African sleeping sickness |
Is it C-shaped trypanosomes in the blood?
Is it a trypanosomal disease with the chief problem weakness of
the
esophagus, colon, bladder, or heart? |
Chagas's disease ("American trypanosomiasis") |
Is it protozoans growing inside the cells of eye, brain, heart,
or
lymphoid tissue? |
Toxoplasmosis |
Is it a worm that looks like a very long piece of macaroni? |
Ascaris |
Is it a little worm that lays its eggs on the anoderm? |
Pinworm |
Is it a little worm with vicious fangs chomping on the duodenum?
Is
the patient perhaps iron-deficient and/or shoeless? |
Hookworm |
Is it a large worm in a contemporary American? |
Consider Strongyloides |
Is it a large worm encysted beneath the skin?
Is your instructor grinning as if he or she is about to explain
the
origin of the medical caduceus? |
Guinea worm ("Dracunculus")
|
Is it a baby worm coiled in a little shell in muscle or
brain? |
Trichina |
Is it a worm in the blood or a lymph node of a person with
elephantiasis? |
Microfilariasis |
Is it a calcified, mummified baby tapeworm that made it to the
brain to
die? |
Cysticercosis |
Is it a cyst full of thousands of baby tapeworms, in the lung,
liver,
or spleen? |
Echinococcus (hydatid cyst) |
Is it a fluke in the bile duct? |
Clonorchiasis or fasciolopsiasis |
Is it the lung fluke? |
Paragonimiasis |
Is it a dead, calcified worm in a lung? |
Dirofilaria |
Is it a mated pair of worms in a vein? |
Schistosomes |
Is it an oval schistosome egg with a large lateral spine? |
Schistosoma mansoni egg |
Is it an oval schistosome egg with a large terminal spine? |
Schistosoma haematobium egg |
Is it a round schistosome egg with a small lateral spine? |
Schistosoma japonicum egg |
Is it non-caseating granulomas without organisms or eggs or
foreign
bodies visible? |
Sarcoidosis or berylliosis or zirconium ("armpit sarcoid")
granulomas |
Is he or she a child, very malnourished, with extreme tissue
wasting,
and perhaps with tetany?
Is he or she a malnourished adult with extreme tissue
wasting? |
Marasmus |
Is he or she a malnourished child with ascites, dependent edema,
fatty
liver, and pigment loss? |
Kwashiorkor |
Is this a malnourished person's eye with Bitot's spots (debris)
and
hyperkeratosis of the cornea (xerophthalmia) leading to corneal
maceration and ulcers? Is he or she a malnourished person or patient with malabsorption, now complaining of night blindness? Is it squamous metaplasia of a gland's duct, or the airways of a non- smoker?
Is it fatal measles pneumonia in a poor child? |
Vitamin A (retinoic acid) deficiency |
Is it increased CSF pressure in a vitamin faddist or child of a
vitamin faddist? Is he or she a person who is sick after eating polar bear liver? Is it fatty change confined to the little Ito cells of the liver?
Is it loss of the sebaceous glands or even columnar metaplasia of
the
epidermis? |
Vitamin A (retinoic acid) toxicity |
Is there normal osteoid which fails to mineralize? Is there nodularity of a child's costochondral junctions ("rosary")? Is there depression of a child's costochondral junctions? Does the child perhaps also have frontal bossing, a square head and/or lumbar lordosis? Are the legs of a malnourished, dark-skinned or house-bound child bowed?
Are the bones of an older person living on a diet deficient in
calcium, or with vitamin D deficiency or resistance, failing to
mineralize? |
Rickets / vitamin D (cholecalciferol) deficiency /
osteomalacia |
Is he or she a chronic alcoholic or malnourished adult with
ophthalmoplegia and cerebellar ataxia, especially on re-feeding
with
carbohydrate? Does he or she have a history of chronic alcoholism or extreme malnutrition? Does the person now "create a personal reality" (i.e., ties a knot in a non-existent string, invents an autobiography)? Is he or she badly nourished and now in high-output heart failure?
Is he or she a past or present alcohol abuser, or a person with a
history of malnutrition, with a peripheral neuropathy in the
glove-
stocking distribution? |
Thiamine (vitamin B1) deficiency (wet or dry beriberi, Wernicke-
Korsakoff syndrome) |
Is he or she a malnourished person with rhomboid, hyperkeratotic
dermatitis, especially where the sun shines or the skin is
irritated? Is he or she a malnourished person with diarrhea and/or dementia and/or "schizophrenia"?
Is he or she a malnourished person eating primarily maize
("corn",
"grits", "hominy", etc.)? |
Pellagra (niacin deficiency, vitamin B3 deficiency) |
Is he or she a person with megaloblastic anemia and nervous
system
complaints? Is he or she a person with either of the above, and atrophic gastritis? Is he or she a person with either of the above, a negative test for syphilis, and demyelinization of the dorsal columns of the spinal cord?
Is he or she a food cultist who will eat nothing of animal
origin,
ever? |
Cobalamin (vitamin B12) deficiency NOTE: "Pernicious anemia", etc., etc.
|
Is he or she a malnourished person with severe gum changes? Is it petechiae around the body hairs, which have become tightly coiled?
Is he or she a malnourished person with a severe hemorrhagic
tendency? |
Scurvy (vitamin C deficiency) |
Is he or she a malnourished person with megaloblastic anemia,
with
normal cobalamin levels and no nervous system problems?
Is he or she somebody who just plain won't eat those
vegetables? |
Folic acid deficiency |
Is he or she somebody with a hypochromic, microcytic anemia that
isn't
thalassemia? Does the peripheral smear show elongated, pale RBC's ("pencil cells")?
Is that somebody a teenaged girl living on junk food, or somebody
with
a bleeding ulcer or gut cancer or hematuria or hookworm? |
Iron deficiency |
Is it a lung with extremely abundant black pigment concentrated
in
nodules around 1-3 mm across?
Is it a cluster of carbon-laden macrophages packing an alveolus
adjoining a respiratory bronchiole, without significant
fibrosis? |
Coal macules (simple coal worker's pneumoconiosis) |
Is it "eggshell calcification" in a hilar lymph node? Is it a lung or mediastinal lymph node that contain many sharply- demarcated, hard white spheres like pearls?
Is it concentrically-layered fibrosis near a respiratory
bronchiole,
rimmed by macrophages? |
Silicosis
|
Is it rheumatoid nodules in the lung of a person with coal or
silica
dust exposure? |
Caplan's syndrome |
Is it a massive, dense, black lesion occupying most or all of one
lobe
of the lung of a coal worker? |
Progressive massive fibrosis |
Is it silicosis plus abundant carbon? |
Anthracosilicosis |
Does it look like a hemosiderin barbell in the lung? Is it alveolar septa thickened by collagen in a person with a history or other evidence of asbestos exposure? Is it a dense fibrous plaque on the pleura, especially the parietal pleura?
Is it a malignant mesothelioma? |
Asbestos exposure |
Is it cherry-red livor mortis in a body not dead from cold
exposure or
cyanide? Is it symmetric necrosis of the globus pallidus on either side? Is it a body found dead in a car in a closed garage, with the ignition on and the gas tank empty? Is it a body found in a house adjoining such a suicide?
Is it an entire family with ill-defined symptoms including
headache,
all sick at the same time, and all recovering soon after leaving
their
house? |
Carbon monoxide |
Is it birefringent crystals found in the kidney and meninges in a
person with profound metabolic acidosis? |
Ethylene glycol (antifreeze) poisoning |
Is it birefringent crystals in the pulmonary vasculature? Is he or she a person with many depressed skin craters?
Is he or she a person with many fibrous scars over the veins? |
Injected drug abuse |
Is it tissue with hyalinized muscular arteries, perhaps with
endothelial swelling, together with abnormally large and
hyperchromatic
nuclei in cells outside the vessels? |
Radiation effect |
Is it arborizing marks on the skin? Is it a gray char mark where the skin contacted metal or was grounded?
Is it calcified collagen (not just dystrophic calcification, but
electroplating)? Is there perhaps a history of modern style
torture? |
Electrical burn |
Is it fluid in a circular area under a newborn's scalp? |
Caput succedaneum
|
Is it a circular bleed under a newborn's scalp? |
Cephalhematoma |
Is it a brachial plexus injury, perhaps leading to a withered
arm,
sustained during birth? |
Erb's palsy or Klumpke's palsy |
Was it person born with seal limbs (phocomelia)? |
Consider thalidomide effect
NOTE: There are other causes. |
Is he or she a child with short palpebral fissures, a small
maxilla,
and mental retardation? |
Fetal alcohol syndrome |
Are the nose and ears flattened, and the limbs bent out of
shape? |
Oligohydramnios sequence |
Are some or all of the organs in the body backwards (i.e., heart
on the
right, liver on the left, spleen on the right)? |
Situs inversus (complete or partial)
NOTE: Ask about ciliary dyskinesia / Kartagener's! |
Is it an atelectatic lung from a newborn, with fibrin lining the
respiratory bronchioles? |
Hyaline membrane disease (respiratory distress of the
newborn) |
Is it squames in the alveoli of a baby born alive or dead? |
Aspiration of amniotic fluid |
Is it many nucleated red cells circulating in the blood of a
newborn? |
Hemolytic disease of the newborn |
Is he or she a child with cataract, mental retardation, and liver
problems?
Is it a child's liver with fat-laden hepatocytes arranged like
daisy
petals, with or without cirrhosis? |
Galactosemia (the bad kind) |
Is he or she a child with excess salt in the sweat? Is he or she an older child or teen who has had many bacterial lung infections, perhaps with bronchiectasis, without immotile cilia or defective neutrophils or lymphocytes? Is he or she an older child with exocrine pancreatic insufficiency, atrophy of the acini, and viscous plugs in the pancreatic ducts?
Is it a man with normal testes but a missing vas deferens? (May
be
one-dose of the gene.) |
Cystic fibrosis ("mucoviscidosis") |
Is it the body of a baby, aged 1-11 months, with no internal or
external evidence of disease or trauma, no botulism spores in the
small bowel, normal sweat glands and coronary arteries, not found
face-down on bedding with mouth and nose occluded, and an
adequate
death scene investigation has been carried out to remove strong
suspicion of smothering, shaking, hyperthermia, or murder by
insulin,
digitalis, or succinylcholine? |
Idiopathic sudden infant death syndrome |
Is it a tumor on a newborn's sacrum? |
Sacrococcygeal teratoma |
Is it a swollen mass of lymphatic vessels under a child's
chin? |
Cystic hygroma |
Is he or she a retarded person with several of the following: ...a flat facial profile; ...oblique palpebral fissures; ...a large tongue; ...epicanthic folds; ...hypotonic muscles; ...horizonal palmar creases; ...a bent little finger; ...midline cardiac defects; ...mild hypothyroidism? |
Trisomy 21 (Down's syndrome) |
Is he or she a profoundly retarded child with several of the
following: ...increased muscle tone; ...a small jaw; ...a short sternum; ...index and little fingers overlapping middle and ring fingers; ...rocker-bottom feet? |
Trisomy 18 (Edward's syndrome) |
Is he or she a retarded child with a small head, tiny eyes,
arhinencephaly, polydactyly, and multiple other defects, or at
least
most of these?
Does the child have only one eye (cyclops), and/or only one
cerebral
hemisphere (holoprosencephaly)? |
Trisomy 13 (Patau's syndrome) |
Is he or she a retarded child with a tiny head and who mews like
a
cat? |
5p- (cri du chat) |
Is he or she a retarded person with most of these: ...strabismus; ...almond-shaped eye folds; ...a great tendency to overeat and to steal and hide food; ...a gentle demeanor punctuated by violent outbursts? |
Prader-Willi syndrome |
Is he or she a profoundly retarded person with a large jaw, jerky
movements, and who laughs a lot for no apparent reason? |
Angelman syndrome |
Is he or she a retarded child with a single, very thick
eyebrow? |
Cornelia de Lange syndrome |
Is he a sterile, gentle, smooth man with gynecomastia and long
arms and
legs?
Is it a section of testis with Sertoli-only tubules (i.e., no
trace of
spermatogenesis), and an enormous excess of Leydig interstitial
cells? |
XXY (Klinefelter's syndrome) |
Is he a tall, wiry, uncoordinated man with acne and a temper? |
Suspect XYY ("super male") |
Is she a short woman with a webbed neck, small breasts, a shield-
shaped chest, outward-turning elbows, fibrous nubbins ("streak
gonads") instead of ovaries, and who has never menstruated? |
XO (Turner's syndrome) |
Is she a mildly retarded woman whose periods are irregular? |
Suspect XXX ("super female") NOTE: Most XXX's are normal women. |
Do you have histologic evidence that he or she has both ovarian
and
testicular tissue? |
True hermaphrodite |
Is she apparently a woman, but she has no uterus or cycle, and
never
develops body hair? |
Testicular feminization |
Is she a woman with a large clitoris and excessive body hair?
And was
the clitoris large from birth? |
Suspect congenital adrenal hyperplasia (enzyme deficiency)
causing
virilization |
Is he or she a tall, light-boned person with some of: ...arm span greater than height; ...aortic dissection; ...pectus excavatum; ...displacement of the lens of the eye; ...hyper-extensible joints; ...mitral valve prolapse? |
Marfan's syndrome |
Is he or she a person with six or more smooth-edged caf‚-au-lait
spots? Is he or she a person with two or more neurofibromas or acoustic neuromas?
Is he or she a person with elephant-like skin overlying a
neurofibroma? |
Neurofibromatosis (von Recklinghausen's disease) |
Is he or she a person with several of the following: ...ash-leaf poorly-pigmented spots on the skin, with long axis parallel to the dermatomes; ..."adenoma sebaceum" fibrous bumps on nose and chin; ...glial hamartomas lining the cerebral ventricles ("candle gutterings"); ...glial hamartomas ("tubers") replacing the normal cortex; ...scrambled neurons instead of the normal cortical layers; ...cardiac rhabdomyoma; ...renal angiomyolipoma; ...mental retardation; ...seizures; ...behavior problems; ...this seems to be an autosomal dominant affliction with widely variable penetrance? |
Tuberous sclerosis ("epiloia", "Bourneville's disease") |
Is he or she a person with little or no pigment, even in the
eyes? |
Albinism |
Is he or she a person with precocious osteoarthritis and black
cartilages, who notes his or her urine turns dark if it stands in
the
light? |
Alkaptonuria (ochronosis) |
Is it huge crumpled-kleenex ("watered silk") macrophages packing
bone
marrow or spleen? |
Gaucher cell (Gaucher's disease) |
Is it huge foamy macrophages packing bone marrow or spleen? |
Niemann-Pick cell (Niemann-Pick disease) |
Is he a mildly retarded male with a long maxilla? |
Fragile X syndrome |
Is it masses of glycogen under the sarcolemmal membrane? |
McArdle's myophosphorylase deficiency |
Is it excess glycogen in the hepatocytes and proximal tubular
epithelial cells? |
von Gierke's G6Pase deficiency |
Is it glycogen packing the heart and skeletal muscle cells of a
baby? |
Pompe's acid maltase deficiency |
Is he or she a person of normal intelligence but with severe,
bizarre
facial deformities? |
Treacher-Collins syndrome |
Is he or she a person with fragile, stretchable cigaret-paper
skin,
hyper-extensible joints, and perhaps a history of bleeding from
fragile
vessels? |
Ehlers-Danlos syndrome
|
Is it non-caseating granulomas in a person exposed to
beryllium? |
Berylliosis |
Is he or she a person with fused fingers and a depressed center
of the
face? |
Apert's syndrome |
Is it a wound without bruising or tissue bridging, and with sharp
edges, and deeper than it is wide? |
Stab wound |
Is it a wound without bruising or tissue bridging, and with sharp
edges, and wider than it is deep? |
Incised wound |
Is it an open wound with rough, bruised edges, and tissue
bridging in
its depths? |
Laceration |
Is it a massive wound which penetrates to, or even through, the
bone? |
Chop wound |
Is it a gunshot wound with stellate tearing of the skin, an
abrasion
ring, a muzzle imprint, no soot and no powder tattooing, and
cherry red
color of the surrounding tissues, or at least most of these? |
Tight contact entry wound
|
Is it a gunshot wound with an abrasion ring, perhaps a muzzle
imprint,
and a ring of soot, or at least most of these? |
Loose contact entry wound |
Is it a gunshot wound with an abrasion ring, no stellate tearing,
no
muzzle imprint, no cherry red color, and powder tattooing? |
Intermediate range (6"-3' or so) entry wound |
Is it a gunshot wound with an abrasion ring, no stellate tearing,
no
muzzle imprint, no cherry red color, and no powder tattooing? |
Long range entry wound |
Is it a gunshot wound with no abrasion ring, and perhaps with
stellate
tearing? And is there an entry wound someplace else? |
Exit wound |
Is it a gunshot wound to the skull with inward beveling? |
Entry wound
|
Is it a gunshot wound to the skull with outward beveling? |
Exit wound |
Is it a body with nail marks on the neck and conjunctival
petechiae? |
Manual strangulation |
Is it a body found hanged without the usual a V-shaped rope
abrasion
with vital reaction? |
Post-mortem hanging; homicide |
Is it a burned body without soot in the trachea? |
Post-mortem burning; suspect homicide plus arson
|
Is it a yellow, minimally-elevated streak on the inner surface of
a
large artery?
Is it a mass of lipid-laden foam cells in the intima of a large
artery, without fibrosis? |
Fatty streak of atherosclerosis ("the precursor") |
Is it a firm, white, slightly-raised fibrous lesion on the inner
surface of a large artery?
Is it a lesion on the intima of an artery with a fibrous cap
overlying
a variable mixture of lipid-laden foam cells, more fibrous
tissue, and
debris containing lipid and cholesterol "needles"? Is there
perhaps
some loss of the underlying elastic of the media? |
Fibrous plaque of atherosclerosis ("the time bomb") |
Is it a fibrous plaque of atherosclerosis which has ruptured,
causing a
thrombus to form on its surface?
Is it a fibrous plaque of atherosclerosis in a small artery, into
which there has been a hemorrhage, so as to elevate its surface
and
occlude the artery? |
Complicated plaque of atherosclerosis ("the killer") |
Is it a mass of blood tracking between elastic layers of the
aorta
and/or one or more of its branches? |
Dissecting hematoma |
Is it dystrophic calcification of the media of an artery, without
compromise of the lumen or involvement of the intima? |
M”nckeberg's medial calcific sclerosis |
Is it a small artery or arteriole in which the media is altered
and now
consists primarily of hyaline, basement membrane-type material
instead
of smooth muscle? And has it process narrowed the lumen? |
Hyaline arteriolar sclerosis
NOTE: Think hypertension, |
Is it a small artery in which there has been rapid, concentric
proliferation of the intima, with severe narrowing of the
lumen? |
Hyperplastic arteriolar sclerosis
NOTE: Think malignant hypertension, scleroderma, hemolytic-uremic
syndrome, or radiation effect |
Is it a small artery in which the intima is thickened by fibrous
tissue? |
Intimal fibrosis of hypertension / old age |
Is there "fibrinoid" necrosis of the small arteries, often with
thrombus formation, perhaps with intimal edema, intimal myxoid
change,
or intimal onion-skinning, without much other evidence of
vasculitis? |
Malignant hypertension |
Is it a granulomatous process concentrated on the inner elastic
membranae of a branch of the external carotid artery? |
Temporal arteritis
|
Is it a fibrous and/or granulomatous process compromising the
aortic
arch and its great vessels? |
Takayasu's pulseless disease |
Is he or she a child with skin and oral lesions, large lymph
nodes,
perhaps a coronary artery aneurysm, and a lesion resembling
polyarteritis nodosa on biopsy? Is the child perhaps of Japanese
ancestry, though living anywhere in the world? |
Kawasaki's mucocutaneous lymph node syndrome |
Is it an inflamed neurovascular bundle, the artery having
undergone
thrombosis, from the extremity of a smoker? |
Buerger's thromboangiitis obliterans |
Is it an aneurysm of the distal aorta or an iliac artery? |
Atherosclerotic aneurysm |
Is it red streaks running from a primary focus of infection
toward the
regional lymph node? |
Lymphangitis
|
Is it a vascular malformation or birthmark composed primarily of
vascular channels containing many RBC's? |
Hemangioma |
Is it a mass of bizarre vessels, with anaplastic endothelial
cells, and
lumens containing red cells? |
Hemangiosarcoma ("angiosarcoma") |
Is it a malformation or birthmark composed primarily of vascular
channels containing no RBC's? |
Lymphangioma |
Is it a mass of bizarre vessels, with anaplastic endothelial
cells, and
lumens devoid of red cells? Is there perhaps a history of
radiation
and/or lymphedema? |
Lymphangiosarcoma |
Is it a fast-growing mass of little capillaries in a gelatinous
stroma, in the mouth or on the skin? |
"Pyogenic granuloma" |
Is it a tumor composed of well-differentiated spindle cells, and
the
reticulin stain reveals they are surrounded by reticulin just as
normal
pericytes are? |
Hemangiopericytoma |
Is it an adult's left ventricle thicker than 1.5 cm? Is it an adult's right ventricle thicker than 0.5 cm?
Is it heart with very thick fibers with squared ("boxcar") nuclei
that
appear more than twice as large as the nuclei of the endothelial
cells? |
Myocardial hypertrophy |
Is there a major abnormality of the anatomy of the heart, in the
absence of rupture or suppuration? |
Congenital heart disease
NOTE: Yes, Doc, you can puzzle it out! |
Is there an irregular mound of calcified tissue in each sinus of
Valsalva of an older person's otherwise-normal aortic valve? |
Calcific aortic stenosis |
Is it an aortic valve with only two cusps, whether or not the
valve is
stenotic or calcified? |
Congenital bicuspid aortic valve |
Is it an aortic root which has dilated, rendering the aortic
valve
incompetent? |
Syphilis / HLA-B27 inflammatory disease / Marfan's / aortic
dissection |
Is it a mitral valve with the posterior leaflet nearly as long as
the
anterior leaflet?
Is it a mitral, aortic, or tricuspid valve with the leaflets or
cusps
billowing and redundant, like the cells of a parachute? |
Barlow's mitral valve prolapse |
Is it a person who recently had a streptococcal throat infection,
and
now has several or all of the following: fever; ...migratory polyarthritis; ...a bad EKG; ...painful subcutaneous nodules ...erythema marginatum; ...Sydenham's chorea ("St. Vitus Dance")? Is it a cardiac valve with little red wart-like excrescences all along its lines of closure?
Is it a cluster of cells that look like shrunken cardiac myocytes
but
with the histochemistry of macrophages, and with caterpillar-like
heterochromatin if the nucleus is sectioned lengthwise (i.e., it
is an
Aschoff nodule)? |
Acute rheumatic fever
NOTE: Jones criteria if the patient is living. |
Is it a cardiac valve with leaflets thickened by white scar
tissue, and
stuck together for some distance at their edges? Is it a mitral or tricuspid valve with thickened, or even fused, chordae tendineae?
Is it mitral stenosis? |
Damage from rheumatic fever |
Is it masses containing a variable mix of bacteria, fibrin, and
neutrophils, hanging on a previously-normal cardiac valve, which
is now
perhaps damaged? |
Acute bacterial endocarditis |
Is it masses, perhaps quite large, containing a variable mix of
bacteria, fibrin, and neutrophils, hanging on a
previously-damaged
cardiac valve or the site of turbulence in a malformed heart? |
Subacute bacterial endocarditis |
Is it a mass of fibrin without bacteria, on the valve of a person
who
has a chronic, debilitating sickness? |
Marantic (non-bacterial thrombotic) endocarditis |
Is it fibrin vegetations over various surfaces of a cardiac
valve, in a
lupus patient? |
Libman-Sacks endocarditis |
Is it fibrosis of the tricuspid and pulmonic valves, with normal
mitral and aortic valves? |
Carcinoid heart disease |
Is it lymphocytes densely infiltrating a heart? |
Coxsackie / autoimmune / allograft myocarditis |
Is it myocardium that is just too stiff to beat? |
Restrictive cardiomyopathy (i.e., probably amyloid) |
Is it a heart with irregularly thickened muscle, typically
occluding
the outflow track from the left ventricle? Is it myocardial cells arranged crisscross on a light micrograph? Is there also some thickening of the intima of the small arteries?
Is it myocardial sarcomeres arranged crisscross on an electron
micrograph? |
Hypertrophic cardiomyopathy (á-myosin gene, others) |
Is it a heart with muscle that is just too weak to beat properly?
Are
the ventricles flabby and much-dilated, perhaps with mural
thrombi? |
Dilated cardiomyopathy (innumerable causes) |
Is it a heart with a hypertrophic left ventricle, and there is no
explanation other than past or present hypertension? |
Hypertensive heart disease |
Is it a heart, clinically from a recent myocardial infarct victim
or
with a fresh occlusive coronary artery lesion, and you see, under
the
microscope, only wavy fibers at the border of where the infarct
should
be, or perhaps contraction bands? |
Myocardial infarct, 0-4 hours |
Is it a heart, clinically from a recent myocardial infarct victim
or
with a fresh occlusive coronary artery lesion, and you see, under
the
microscope, early coagulation necrosis and perhaps a few
neutrophils? |
Myocardial infarct, 4-12 hours |
Is it a heart with a soft spot in the distribution of an artery
or the
subendocardial watershed?
Is it a heart, and you see, under the microscope, obvious
coagulation
necrosis and more than just a few neutrophils? |
Myocardial infarct, 12-24 hours |
Is it a heart, and there is yellow discoloration in the
distribution of
an artery or the subendocardial watershed?
Is it a heart, and you see, under the microscope, widespread
karyorrhexis, lost cross-striations, and lots and lots of
neutrophils? |
Myocardial infarct, 24-72 hours |
Is it a heart with a visible infarct with a thin red rim?
Is it a heart, and you see, under the microscope, resorption of
the
myocardial fibers and a thin rim of granulation tissue at the
edges? |
Myocardial infarct, 3-7 days |
Is it, grossly and microscopically, a fully-developed scar at the
site
of a myocardial infarct? |
Myocardial infarct, 7 weeks or more |
Is it a person with a serious primary lung disease who also has a
much-hypertrophied right ventricle? |
Cor pulmonale |
Is it a person with three-vessel coronary disease each with 70%
or
greater stenosis, or a serious coronary artery malformation? And
did
it person die suddenly without other evidence of disease,
poisoning, or
injury? And at autopsy, did you find no infarct, or at most a
few wavy
fibers? |
Sudden cardiac death |
Is it endocardial fibrosis causing restrictive cardiac disease,
in a
young person from Africa? |
Endocardial fibroelastosis |
Is it endocardial fibrosis causing restrictive cardiac disease,
and are
there excess eosinophils in blood, heart, and elsewhere? |
Loeffler's eosinophilic endocarditis |
Is it a shaggy covering on the pericardium? |
Fibrinous pericarditis |
Is it a pericardial cavity packed with soft white tumor? And
there is
no other apparent primary? |
Pericardial mesothelioma |
Is it a round mass, like a wrecking ball, in the left atrium,
hanging
on the interatrial septum? |
Atrial myxoma |
Is it a hamartoma in the heart muscle of a person with tuberous
sclerosis? |
Cardiac rhabdomyoma |
Is it several tumor nodules embedded in the myocardium? |
Metastases to the heart |
Is it a peripheral smear with spherocytes, i.e., RBC's without
central
pallor, and the person has a lifelong mild anemia and is Coombs
negative? |
Hereditary spherocytosis |
Is it a peripheral smear with spherocytes, i.e., RBC's without
central
pallor, and the person is Coombs positive? |
Autoimmune hemolysis with spherocytosis |
Is it a peripheral smear with an excess (more than 1-2%) of
slightly
large, slightly-purple staining RBC's (young reds,
reticulocytes)? |
Anemia of blood loss or increased destruction or early release of
red
cells |
Is it a peripheral smear with RBC's containing small round masses
of
condensed DNA? |
Howell-Jolly bodies (think of absence of spleen) |
Is it a peripheral smear with RBC's containing iron-laden
mitochondria? |
Pappenheimer bodies (think of absence of spleen or sideroblastic
anemia) |
Is it a peripheral smear, perhaps specially prepared, containing
Heinz
bodies? |
Erythrocyte enzyme defect or hemoglobin H disease |
Is it a peripheral smear bearing many target cells and some
sickled
cells? |
Sickle cell disease ("Hemoglobin SS") |
Is it a peripheral smear with an unusually large number of target
cells, but no sickled cells? |
Think of hemoglobin C or E diseases or traits or thalassemia |
Is it a smear made at low pH, with target cells and rod-shaped
intracellular crystals? |
Hemoglobin C |
Is it a smear with many target cells and RBC's with bizarre
("birds in
flight", etc.) crystals? |
Sickle-C disease ("Hemoglobin SC disease") |
Is it a smear with target cells, and some cells with coarse
basophilic
stippling, from a person with Hgb around 11 and MCV around
67? |
Beta thalassemia minor |
Is it a smear from a child with severe anemia, a crewcut skull
x-ray,
skull deformity, and many bizarre and/or basophilic stippled
RBC's? |
Beta thalassemia major |
Is it a smear from a person with mild or no anemia and mild
microcytosis, without other evidence of illness? |
Alpha thalassemia trait (2 deletions) |
Is it a person with small red cells, hemolysis and hemoglobin
H? |
Hemoglobin H disease (à-thal, 3 deletions) |
Is it an edematous (i.e., anemia led to high-output congestive
heart
failure) stillborn with abundant hemoglobin Bart's (four gamma
chains)? |
Hydrops fetalis thalassemia (à-thal, 4 deletions)
NOTE: There are other causes of an edematous stillborn, notably
hemolytic disease of the newborn |
Is it a peripheral smear with RBC's fragmented into schistocytes
(helmet cells, blister cells, etc.)? |
Microangiopathic hemolysis; think of DIC, TTP, vasculitis,
malignant
hypertension, burns |
Is it a peripheral smear with hypersegmented ("right-shifted")
neutrophils (one with >5 lobes, 5% or more with 5 lobes) or
hypersegmented eosinophils (one with >2 lobes)? Do you recognize megaloblasts in the bone marrow? Is the MCV well above 100 fL and you're not dealing with alcoholism, thyroid disease, or liver disease, and the MCV is not elevated due to reticulocytosis?
Is the MCV 130 fL or more? |
Megaloblastic anemia NOTE: Common to all these is difficulty making DNA. The RBC cytoplasm matures, but the nucleus can't.
Think of cobalamin (vitamin B12) deficiency, folic acid
deficiency, or
antimetabolite therapy. |
Is it a peripheral smear with small RBC's?
Is the MCV lower than about 80 fL? |
Microcytic anemia
NOTE: The problem is inability to make hemoglobin. it may be due
to
absolute or functional lack of iron ("iron-deficiency anemia",
"anemia
of chronic disease", or "sideroblastic anemia"), inability to
make
porphyrin rings (lead poisoning, erythropoietic porphyria), or
inability to make globin chains (thalassemia). |
Is it a peripheral smear with small RBC's, but the serum ferritin
is
high and there are abundant marrow iron stores, and there is
chronic
inflammation somewhere in the body? |
Anemia of chronic disease
NOTE: Interleukin 1 is preventing uptake of storage iron into
normoblasts. |
Is it a peripheral smear with small RBC's, perhaps also with a
population of normal RBC's, and there are abundant marrow iron
stores
with a few ringed sideroblasts (i.e., normoblasts with iron-rich
mitochondria)? |
Sideroblastic anemia NOTE: The normoblasts are having difficulty getting iron into the heme rings. |
Is it a peripheral smear with teardrop RBC's and erythroid and
myeloid
marrow elements? |
Leukoerythroblastic smear
NOTE: Think of tumor or TB in the marrow, or agnogenic myeloid
metaplasia. |
Is it a peripheral smear with RBC's with projections having
bulbous
ends? |
Acanthocytes; think abetalipoproteinemia |
Is it a peripheral smear with RBC's with short, stubby
projections like
gears? |
Crenated red cells, artifact, usually means nothing |
Is it a peripheral smear with RBC's innumerable radiating grooves
on
their edges, like plastic checkers pieces? |
Artifact; somebody dripped water in the Wright's stain |
Is it a peripheral smear with fewer than around 6 platelets per
high
power field? |
Thrombocytopenia |
Is it thrombocytopenia, and are there some very large (i.e.,
rush-job)
platelets? |
Platelet lysis; think of ITP |
Is it thrombocytopenia, and are there also schistocytes?
And are there tiny fibrin-platelet thrombi in the small vessels
of many
organs, outstandingly the renal glomeruli? |
Probably DIC (disseminated intravascular coagulation, and you
must find
out why!) |
It is a person with a fever, neurologic defects, schistocytes,
thrombocytopenia, and renal failure?
Are there tiny, very hyaline-looking fibrin-platelet thrombi in
the
small arteries and capillaries of many organs? |
TTP (thrombotic thrombocytopenic purpura) |
Is it mouth ulcers in a neutropenic person?
Is it a blood smear with very few neutrophils as the principal
abnormality? |
Agranulocytosis |
Is it a smear with many immature (band, maybe even younger)
neutrophils? |
"Left shift" |
Is it a neutrophil with very prominent, blue-staining
granules? |
Toxic granulation |
Is it a neutrophil with very prominent, red-staining
granules? |
Alder-Reilly anomaly, i.e., Hunter's, Hurler's |
Is it a pale blue blob inside a neutrophil? |
D”hle body |
Is it a cell that stains positive for CD4? |
T-helper lymphocyte or dendritic macrophage ("Langerhans
histiocyte") |
Is it a cell that stains positive for CD8? |
T-suppressor lymphocyte |
Is it a small cell with a surface that stains positive for kappa
chains or lambda chains? |
B-lymphocyte |
Is it a cell that with cytoplasm that stains positive for kappa
chains, lambda chains, and/or one of the heavy chain types? |
Plasma cell |
Is it a cell that stains positive for lysozyme, nonspecific
esterase,
or anti-chymotrypsin?
Is it a cell that has eaten one or more RBC's? |
Monocyte - macrophage |
Is it a free cell that stains positive for tartrate-resistant
acid
phosphatase?
Is it a lymphocyte with many apparent hairs sticking from it, as
seen
on a smear of peripheral blood? And was the bone marrow tap
dry? |
Hairy cell leukemia |
Is it a cell that stains positive for myeloperoxidase,
chloroacetate
esterase, or with the Sudan Black lipid stain? |
Granulocyte |
Is it a lymphocyte about 8 microns across, with a dense,
smooth-surfaced
nucleus and scanty cytoplasm? |
Normal B or T lymphocyte, or well-differentiated lymphocytic
lymphoma
or chronic lymphocytic leukemia. |
Is it a lymphocyte about 8 microns across, with an irregular nuclear
membrane? |
Small cleaved activated B-lymphocyte |
Is it a lymphocyte about 16 microns across, with an irregular nuclear
membrane? |
Large cleaved activated B-lymphocyte |
Is it a lymphocyte about 16 microns across, with a smooth nuclear
membrane? |
Small non-cleaved activated B-lymphocyte |
Is it a lymphocyte about 25 microns across, with a smooth nuclear
membrane? |
Large non-cleaved activated B-lymphocyte |
Is it a lymphocyte about 30 microns across, with a very large nucleus,
a very
large nucleolus, and basophilic cytoplasm? |
B- or T-immunoblast |
Is it a peripheral smear with striking granulocytosis and left
shift,
and is there abundant staining for leukocyte alkaline
phosphatase, and
are Philadelphia chromosome and bcr/abl absent? And you
know
something's seriously wrong (cancer, bad infection, other) with
the
patient? |
Leukemoid reaction |
Is it a peripheral smear with striking granulocytosis and left
shift,
and is there very poor staining for leukocyte alkaline
phosphatase, and
is Philadelphia chromosome (or at least bcr/abl
present? |
Chronic granulocytic ("myelogenous") leukemia |
Are the neutrophil nuclei hypo-segmented, with "peanuts" and
"eyeglasses", but the patient is not sick? |
Pelger-Huet anomaly |
Is it a benign lymph node with tremendously enlarged follicles,
all
rimmed by the normal mantle? |
Follicular (i.e., B-cell) hyperplasia
NOTE: Think of AIDS-related complex, rheumatoid disease,
syphilis,
common variable immunodeficiency |
Is it a benign lymph node with prominent follicles and puny
granulomas? |
Toxoplasmosis |
Is it a benign lymph node with lots of activated cells in the
cortex
between normal-appearing lymphoid follicles? |
Paracortical (i.e., T-cell) hyperplasia
NOTE: Think of phenytoin effect, infectious mononucleosis,
lupus |
Is it a benign lymph node with very prominent macrophages in the
sinusoids? |
Sinus histiocytosis (i.e., macrophage hyperplasia)
NOTE: Think of a node draining a cancer |
Is it a benign but hyperplastic lymph node, with both lipid and
melanin in the macrophages? |
Dermatopathic lymphadenitis |
Is it a lymph node with abundant blood vessels and sheets of
immunoblasts? |
Angioimmunoblastic lymphadenopathy |
Does it stain positive for CD1 (T6) and S100?
Does it contain a Birbeck pentalaminar tennis-racket shaped
structure? |
Dendritic macrophage / Histiocytosis X / Langerhans cell
histiocytosis |
Is it a proliferation of normal appearing or activated
lymphocytes,
destroying the architecture of a tissue? And is monoclonality demonstrated by finding only kappa or only lambda chains? And is monoclonality demonstrated by morphologic uniformity of cells? And is there scanty, if any, vascular proliferation in response to the growth? And are the monoclonal cells perhaps invading surrounding tissue? And is there perhaps necrosis, in the absence of some cause of inflammation? And if nodularity is present, do the nodules lack a proper mantle?
Are classic gene rearrangements (immunoglobulin for B-cells,
receptors
for T-cells) perhaps present? |
Malignant lymphoma |
Is it a small lymphoma-leukemia cell with an extremely convoluted
nucleus? |
S‚zary cell |
Is it an aggressive lymphoma or leukemia arising in the setting
of
chronic lymphocytic leukemia or low-grade lymphocytic
lymphoma? |
Richter's syndrome |
Is it a diffuse lymphoma composed of cells that exactly resemble
normal resting lymphocytes?
Is it the solid phase of chronic lymphocytic leukemia? |
Well-differentiated lymphocytic lymphoma / small lymphocytic
lymphoma |
Is it a diffuse lymphoma composed of cells that resemble normal
resting lymphocytes but have slightly more cytoplasm, which
stains
basophilic? Is there, perhaps, also a Waldenstr”m's IgM pentamer paraprotein? And/or are there apparent intranuclear immunoglobulin deposits (Dutcher bodies)? Is the primary in the gut, and the tumor makes alpha heavy chains?
Does the tumor make gamma or mu heavy chains? |
Plasmacytoid small lymphocytic lymphoma / Waldenstr”m's
macroglobulinemia / heavy chain disease |
Is it a nodular or diffuse lymphoma composed of cells that
resemble
normal resting lymphocytes but have irregular nuclear
membranes? |
Small cleaved cell lymphoma |
Is it a nodular or diffuse lymphoma made up of a mix of small
cleaved
and larger lymphocytes, both being neoplastic? |
Small cleaved and large cell lymphoma |
Is it nodular or diffuse lymphoma composed of larger lymphocytes,
typically larger than an endothelial cell? (An endothelial cell
is
around 15 microns.) |
Large cell lymphoma |
Does it look like a diffuse large cell lymphoma, but is composed
of
cells that truly bear histiocytic markers? |
True histiocytic "lymphoma" |
Does it look like a diffuse anaplastic lymphoma, with
erythrophagocytosis? |
Malignant histiocytosis |
Is it a diffuse lymphoma composed of B- or T-immunoblasts? |
Immunoblastic lymphoma |
Is it a T-cell lymphoma from the thymic region of a young person?
And
are the nuclei a bit clefted? |
T-lymphoblastic lymphoma |
Is it a lymphoma composed of fairly large cells with almost no
cytoplasm and very little in the way of differentiation, with
tiny
lipid droplets in the cytoplasm which concentrate (when the tumor
cells
die) inside macrophages, imparting the "starry sky" appearance?
And is
the famous 8:14 myc-immunoglobulin translocation, or something
similar,
present? |
Burkitt's lymphoma
NOTE: If this is from an African child, it's usually in the jaw
and the
child is EBV positive. In the U.S. form, it can be from
anyplace. |
Is it a T-cell lymphoma, perhaps composed of S‚zary cells, with
little
clusters of neoplastic cells ("Pautrier microabscesses") in the
epidermis? |
Mycosis fungoides / S‚zary syndrome
|
Is it an aggressive T-cell lymphoma in an adult who is HTLV-1
positive? |
Aggressive adult T-cell lymphoma-leukemia |
Is it a large cell with a convoluted nucleus, appearing in
section as
two or more nuclei, each with an eosinophilic nucleolus around 7
microns
across, and marginated chromatin? Further, is the background
fitting
for some form of Hodgkin's disease? |
Reed-Sternberg cell |
Is it sheets and sheets of normal-appearing lymphocytes,
punctuated
with occasional Reed-Sternberg cells and their "uninuclear"
variants? |
Lymphocyte predominance Hodgkin's disease |
Is it a mix of lymphocytes, plasma cells, histiocytes, and
eosinophils, with frequent Reed-Sternberg cells and their popcorn
variants? |
Mixed cellularity Hodgkin's disease |
Is it a hideously anaplastic tumor, recurring in a patient with a
previous diagnosis of Hodgkin's disease? |
Lymphocyte depletion Hodgkin's disease |
Is it a mix of lymphocytes, plasma cells, histiocytes, and
eosinophils, with occasional Reed Sternberg cells and their
lacunar
variant, in nodules demarcated by more or less impressive fibrous
bands? |
Nodular sclerosing Hodgkin's disease |
Is it a blood cell about 15 microns across, with a big all-euchromatin
primitive nucleus, several nucleoli, and scanty, basophilic
cytoplasm? |
Blast |
Is it a blast with an Auer rod in its cytoplasm?
Is it a blast that stains positive for chloroacetate
esterase? |
Granulocytic blast |
Is it a blast that stains positive for nonspecific esterase? |
Monocytic blast |
Is it a peripheral smear with abundant circulating blasts?
Is it a bone marrow smear or section with abundant blasts? |
Acute leukemia |
Is it acute leukemia, determined to be of lymphoid origin, and
the
blasts are <15 microns and look just plain primitive? And is the
patient a
younger child? |
Acute lymphoblastic leukemia, L1 |
Is it acute leukemia, determined to be of lymphoid origin, and
the
blasts are >15 microns with clefted nuclei and lots of nucleoli? Is
the
patient perhaps a teen or adult? |
Acute lymphoblastic leukemia, L2 |
Is it acute leukemia, with cells maybe 20 microns, with intracellular
lipid
and a Burkitt chromosome translocation? |
Acute lymphoblastic leukemia, L3 |
Is it acute leukemia with generic, undifferentiated
myeloblasts? |
Acute myelogenous leukemia, M1 |
Is it acute leukemia with some promyelocytic differentiation and
perhaps an Auer rod or two? |
Acute myelogenous leukemia, M2 |
Is it acute leukemia with a preponderance of obvious
promyelocytes,
many Auer rods (red crystalloids in the cytoplasm), and a
tendency for
the patient to develop DIC? |
Acute myelogenous leukemia, M3 / Acute promyelocytic leukemia |
Is it acute leukemia with blasts featuring both granulocytic and
monocytic differentiation? |
Acute myelogenous leukemia, M4 / Acute myelomonocytic
leukemia |
Is it acute leukemia with blasts featuring only monocytic
differentiation? |
Acute myelogenous leukemia, M5 / Acute monocytic leukemia |
Is it acute leukemia with blasts featuring normoblast-like
differentiation, with big chunks of PAS-positive material? |
Acute myelogenous leukemia, M6 / DiGuglielmo's
erythroleukemia |
Is it acute leukemia with a fibrotic bone marrow and blasts with
platelet markers? |
Acute myelogenous leukemia, M7 / Acute megakaryocytic
leukemia |
Is it a solid, discrete mass from someone with acute myelogenous
leukemia, and did the mass turn green on exposure to air? |
Chloroma |
Is it a peripheral smear with a preponderance of normal-appearing
lymphocytes, some of which have been smashed ("smudged") on
preparation of the smear? |
Chronic lymphocytic leukemia |
Is it a spleen bearing erythroid islands and megakaryocytes? |
Extramedullary hematopoiesis |
Is it sheets of plasma cells in bone marrow? Is it large, bizarre plasma cells? Is it punched-out lesions of bone with other findings suggestive of plasma cell myeloma? Is it precocious osteoporosis with other findings suggestive of plasma cell myeloma? Is it urine containing immunoglobulin light chains ("Bence-Jones" protein)? Is it kidney with non-pigmented casts in the tubules and a foreign-body reaction to these casts?
Is it a monoclonal gammopathy, with depression of albumin and
other
globulins? |
Plasma cell myeloma ("multiple myeloma") |
Is it bone marrow replaced by fibrous tissue? |
Think of myelofibrosis, agnogenic myeloid metaplasia, acute
megakaryocytic leukemia, burned-out polycythemia vera |
Is it an apparent tumor that stains strongly for CD1 (T6), and/or
exhibits Birbeck granules (pentalaminar tennis rackets) on
electron
microscopy? Does your instructor perhaps appear extra excited
over
this specimen? |
Langerhans cell histiocytosis / histiocytosis X / Letter-Siwe /
Hans-
Schuller-Christian / Eosinophilic granuloma |
Is it a newborn's lung that appears never to have been aerated,
but
grossly resembles India rubber? Is it a lung crunched very small because of a pleural effusion, a pneumothorax, massive ascites, obstruction of a large airway, or ischemic from a large pulmonary embolus? Is it the basal portion of the lung from a patient with recent abdominal surgery, in which deep inspiration is painful?
Is it lung in which the large majority of alveoli are collapsed,
due to
one of the reasons above, or because of diffuse alveolar damage
(respiratory distress syndrome) with loss of surfactant? |
Atelectasis |
Is it a lung that is beefy red throughout, perhaps worst in its
dependent areas?
Is it lung with much-dilated venules, and perhaps some small
hemorrhages without apparent vasculitis? |
Acute pulmonary congestion
|
Is it brown lung, perhaps more brown in the dependent areas,
perhaps
with some fibrosis?
Is it lung with many hemosiderin-laden macrophages, and perhaps
also
with interstitial fibrosis? |
Chronic pulmonary congestion |
Is the lung wet and heavy, but there is still air in the alveoli
(i.e., there is still crepitus)? Is it lung with thickening of the alveolar septa, which appear pale on microscopy?
Is it heavy lung without excessive fibrosis, from which a modest
among
of fluid runs on sectioning? |
Interstitial pulmonary edema |
Is it heavy, wet lung with frothy bubbles in the large airways?
And is
the lung relatively airless (i.e., lacking in crepitus)?
Is it lung with interstitial edema, and some fluid still visible
in the
alveoli after processing? |
Intra-alveolar pulmonary edema |
Is it very heavy, pale lung, perhaps with focal hemorrhages, and
is the
history short (days to weeks)?
Do you see most or all of the following: |
Diffuse alveolar damage (adult respiratory distress syndrome,
ARDS,
"shock lung", "bronchopulmonary dysplasia" of newborns, Da Nang
lung,
etc., etc.)
Causes: Shock, massive trauma, oxygen toxicity, sepsis, near-
drowning, aspiration, viruses, radiation injury, drug
idiosyncracy,
etc., etc. |
Is it a laminated thrombus in a pulmonary artery, perhaps with
some
adhesion to the wall, perhaps with propagation in the distal
arterial
tree, and not at a site of surgery on the lung?
Is it a laminated thrombus in a pulmonary artery seen
histologically,
perhaps being entered by fibroblasts and angioblasts where it
adheres
to the endothelium, and not at a site of surgery on the lung? |
Pulmonary thromboembolus |
Is it a pulmonary artery or arteriole with any of these: ...atherosclerosis; ...extra layers of cells in its intima and/or media; ...reduplicated elastic lamina; ...the multi-channel "plexiform" lesion replacing the single lumen? |
Vascular changes suggestive of pulmonary hypertension |
Is it squamous metaplasia of the bronchial epithelium? Is it patchy loss of cilia on the bronchial epithelium? Is it extra goblet cells in the bronchial epithelium in the absence of asthma? Is it bronchial glands that extend more than half the way between epithelium and cartilage ("Reid index" > 0.5 or so)? Is it a very thick basement membrane under respiratory epithelium? Is there a big yellow hocker in an airway?
Is there a mass of mucus laden with neutrophils (microscopic
appearance
of a big yellow hocker) in an airway? |
Suspect cigaret smoking as the cause; consider "chronic
bronchitis" if
clinical picture warrants
NOTE: "Cigaret" is the preferred spelling. "-ette" means little
and
cute, the tobacco habit isn't. |
Is it a lung with poor elastic recoil (i.e., a finger impression
holds
water 5 seconds after release)? Is it a diaphanous, relatively insubstantial lung with blebs? Is it a pair of lungs so hyperinflated that they overlap in front of the heart?
Is it a section of lung with relatively few alveolar septa, and
those
that are present relatively depleted of vessels? Are many loose
septa
apparently flapping in the breeze? |
Emphysema |
Is it a properly-prepared emphysematous lung, and the worst
damage is
right around the respiratory bronchioles, where the smoke arrives
first? |
Centrilobular emphysema, suspect cigaret smoking |
Is it a properly-prepared emphysematous lung, and all portions of
the
lobule seem equally damaged? |
Panacinar emphysema, suspect à1-protease inhibitor
("antitrypsin")
deficiency |
Is it an autopsy lung without significant emphysema, scarring or
bronchiectasis, but with all the medium-sized airways occluded by
thick mucus plugs? Is it a lung with goblet cell hyperplasia and/or a thick basement membrane, but not enough exposure to tobacco smoke or air pollution to explain these?
Is it sputum laden with "Curschmann's spirals"? If there is
allergy,
are there perhaps Charcot-Leyden crystals (elongated red-staining
lozenges of eosinophil protein)? |
Asthma |
Is it a lung with dilated large airways, their mucosa disfigured
by
running sores?
Is it a photomicrograph of a lung airway which is extensively
ulcerated, or bearing regenerating epithelium and surrounded by
granulation tissue, or perhaps even replaced by fibrin and
pus? |
Bronchiectasis
Consider cystic fibrosis ("mucoviscidosis"), post-pertussis,
post-
necrosis, Kartagener's immotile cilia, immune deficiency, or near
an
obstructive lesion |
Is it lung with consolidation, suppuration, and probably
hemorrhage,
involving a single lobe, stopping only at the interlobar
boundaries?
Is the involved lung pretty much airless (i.e., there is little
or no
crepitus)? And on microscopy, are the alveolar spaces packed
with
neutrophils? |
Lobar pneumonia "red hepatization"
Think pneumococci, klebsiella |
Is it an electron micrograph of a cilium, lacking the dynein
arms?
Does the patient have bronchiectasis, nasal sinus problems, and
perhaps
also situs inversus? |
Immotile cilia / Kartagener's |
Is it lung with patchy consolidation, suppuration, and maybe
little
hemorrhages, involving several portions of several lobes? Is the
involved lung pretty much airless (i.e., there is little or no
crepitus)? And on microscopy, are the alveolar spaces packed
with
neutrophils? |
Bronchopneumonia |
Is it lung with patchy or lobar consolidation but more gray-
appearing? Is the involved lung pretty much airless (i.e., there
is
little or no crepitus)?
Is it lung with balls of loose collagenous tissue forming within
the
alveoli amid debris of macrophages, dead cells, fibrin, and
perhaps
polys? |
Resolving bronchopneumonia or resolving lobar pneumonia "gray
hepatization" |
Is it a lone caseating granuloma in the lung, typically under the
pleura of the midportion?
And do acid-fast stains show mycobacteria, and/or are stains for
fungi
(i.e., histoplasmosis) negative? |
Healed primary tuberculosis, probably an old "Ghon focus" |
Is it a lone caseating granuloma of tuberculosis under the lung
pleura, and is there a second lone caseating granuloma of
tuberculosis
in the hilar lymph node draining this portion of lung? |
Ghon complex of primary tuberculosis |
Is it caseous necrosis with a variable granulomatous response at
the
pulmonary apex? Has a cavity with a white rim perhaps formed?
And
again, do acid-fast stains show mycobacteria, and/or are stains
for
fungi (i.e., histoplasmosis) negative? |
Secondary, reactivation tuberculosis |
Is it innumerable caseating granulomas throughout the lung,
spleen,
liver, and/or peritoneal cavity? And again, do acid-fast stains
show
mycobacteria, and/or are stains for fungi (i.e., histoplasmosis)
negative? |
Miliary tuberculosis |
Is it a lung "whited-out", grossly or on x-ray, by caseation with
a
variable granulomatous response? And again, do acid-fast stains
show
mycobacteria, and/or are stains for fungi (i.e., histoplasmosis)
negative? |
Progressive pulmonary tuberculosis |
Is it a lung with widespread fibrosis, a few air spaces pulled
extra-
wide ("honeycomb lung") especially at the periphery, and there is
no
other evident pathology or apparent cause? |
Diffuse interstitial fibrosis ("usual interstitial pneumonitis",
fibrosing alveolitis, "honeycomb lung", "Hamman-Rich")
Rule out: Bleomycin lung, busulfan lung, nitrofurantoin lung,
amiodarone lung, other drugs; old diffuse alveolar damage (ARDS)
from
any cause, etc. etc. |
Is it an inflamed lung or portion of lung with more air
("crepitus")
than in the familiar lobar pneumonia or bronchopneumonia?
Is it lung with an inflammatory infiltrate, primarily in the
interstitium, probably composed primarily of lymphocytes (though
perhaps with neutrophils early)? Does the picture develop into
ARDS in
fatal cases? |
"Primary atypical pneumonia" / pneumonitis
Consider viral, rickettsial, chlamydial, or mycoplasmal
pneumonitis |
Is it gray, airless, non-fibrotic lung in a patient with poor T-
cell/macrophage function? Are the alveoli filled with
eosinophilic,
frothy-looking material? And do special stains (silver is best)
show
pneumocystis organisms? |
Pneumocystosis |
Is it a lung cavity containing a solid brown mass? |
Aspergillus |
Is it a pneumonitis with smudge cells in the bronchial
epithelium? |
Adenovirus |
Is it a pneumonitis with huge owl-eye inclusion-bearing
cells? |
CMV pneumonitis |
Is it a pneumonitis or bronchiolitis with syncytial (i.e.,
multinucleated) cells in the epithelium of the bronchioles? |
Respiratory syncytial virus |
Is it a pneumonitis with giant cells with nuclei bearing large
inclusions (i.e., Warthin-Finkeldey giant cells)? |
Measles pneumonitis |
Is it a fibrosing alveolitis with clumps of macrophage-like cells
adhering to one another in the centers of the alveoli? |
Desquamative interstitial pneumonitis |
Is it a fibrosing alveolitis with abundant non-caseating
granulomas? |
Sarcoidosis or berylliosis |
Is it a pneumonitis with a variable mix of eosinophils,
neutrophils,
macrophages, and/or acute vasculitis? And is the patient exposed
to
bacterial spores (i.e., farmer, sick building)? |
Organic pneumoconiosis |
Is it a fibrosing process in the lungs with an abundance of
eosinophils and of macrophages with grooved nuclei?
Is it a lung lesion, and your instructor is showcasing a positive
CD1
(T6) stain and/or a Birbeck pentalaminar tennis-racket granule on
an
electron micrograph? |
Eosinophilic granuloma variant of Langerhans cell
histiocytosis |
Is it a diffuse fibrosing alveolitis with an occupational history
of
asbestos exposure? And is your instructor showcasing a
ferruginous
body, or is a malignant mesothelioma or a large pleural plaque
present? |
Asbestosis |
Is the lung packed with eosinophils, but this is not eosinophilic
granuloma variant of Langerhans cell histiocytosis? |
Pulmonary eosinophilia / "eosinophilic pneumonitis"
Consider Loeffler's pneumonia, microfilariasis, nitrofurantoin
lung,
allergy |
Is it a lung with recent (red cells) and/or old
(hemosiderin-laden
macrophages) hemorrhage in the alveoli, but with little else
wrong?
And is there a positive anti-GBM antibody in the serum and/or a
linear
pattern of fluorescence for IgG in the glomerulus and/or alveolar
septa? |
Goodpasture's disease |
Are normal-appearing alveoli more-or-less uniformly packed with a
homogeneous, gelatinous, very finely-granular eosinophilic
material? |
Alveolar proteinosis
Consider acute silicosis, immunosuppression, opportunistic lung
infection, lymphoma; many are "idiopathic" |
Are the alveoli packed with foamy macrophages without a lot of
necrosis? |
Lipid pneumonia
Consider aspiration of animal, vegetable, or mineral oil;
obstruction
of a large airway |
Is it a lung cancer (bronchogenic carcinoma) with histology
showing
single-cell keratinization, pearl formation, and/or obvious
intercellular bridges? Is it a lung cancer with obvious and abundant desmosomes and/or tonofilaments on electron microscopy? |
Squamous cell carcinoma of the lung
Most of these present as hilar masses, and they tend to
cavitate. |
Is it a lung cancer making mucin and/or forming good glands
and/or
forming good papillae? Is it a lung cancer with intracellular lumens on electron microscopy?
Is it a cancer that immunostains positive for surfactant? |
Adenocarcinoma of the lung Most of these present as peripheral masses.
Rule out metastasis to lung. |
Is it a lung cancer (bronchogenic carcinoma) presenting as masses
of
mucoid material within the lung parenchyma?
Is it lung cancer with well-differentiated columnar or cuboidal
cells
growing single-file along the alveolar septa? Are they perhaps
producing mucin which fills the alveoli? |
Bronchioloalveolar lung cancer A variation on adenocarcinoma.
Rule out metastasis to lung. |
Is it lung cancer (bronchogenic carcinoma) composed of large
(more than
20 microns or so), anaplastic cells without obvious glandular or
squamous
features? |
Large cell undifferentiated lung cancer
Most of these present as large masses near the hilum. |
Is it lung cancer (bronchogenic carcinoma) composed of small
(around
15 microns), fragile cells with very little cytoplasm ("small blue
cells")?
And is there little or no tendency to form a collagenous
stroma? Does this lung cancer stain strongly with neuron-specific enolase or some other neuroendocrine marker?
Does this lung cancer exhibit neurosecretory granules on electron
microscopy? |
Small cell undifferentiated lung cancer ("oat cell")
The primary is usually fairly small, and the soft white tumor
tends to
spread widely among peribronchial lymphatics |
Is it a round, soft lung mass which in microscopy shows benign-
appearing cuboidal cells in clumps or ribbons? And are
neurosecretory
granules seen on electron microscopy? |
Bronchial carcinoid ("bronchial adenoma") |
Is it a lung or pair of lungs bearing several rounded tumor
nodules
throughout the parenchyma, without a dominant mass? |
Metastases to the lung |
Is it a popcorn-shaped mass in the lung, composed primarily of
cartilage? |
Chondroid hamartoma of the lung |
Is it pus in the pleural cavity, or packing the gallbladder? |
Empyema |
Is it shaggy strands on the pleural surface? |
Fibrinous pleuritis |
Is it milky-white fluid in the pleural cavity, and there has been
trauma or cancerous involvement of the thoracic duct? |
Chylothorax |
Is it air in the pleural cavity? |
Pneumothorax |
Is it a pneumothorax with the mediastinal contents markedly
shifted
toward the opposite side? |
Tension pneumothorax |
Is it a fibrous mass attached to the visceral or parietal pleura,
and
showing no invasive tendency? |
Benign mesothelioma
NOTE: No asbestos link |
Is it a white solid or semi-liquid mass filling a pleural cavity?
(Or
perhaps the pericardial or peritoneal cavity?) On microscopy, is it tumor composed of spindle cells, gland-and/or- papillar, or (typically) both?
Is it cancer with very long, spaghetti-like microvilli on
electron
microscopy? |
Malignant mesothelioma
NOTE: The cause is asbestos exposure. Tobacco is not a
contributor. |
Is it a tumor of small, blue cells, similar to a neuroblastoma,
arising from the olfactory epithelium? |
Olfactory neuroblastoma ("esthesio-neuroblastoma") |
Is it a fibrovascular tumor from the throat of a teenaged
male? |
Angiofibroma |
Is it a lymphocyte-rich squamous cell carcinoma of the throat?
Is the patient perhaps Chinese? Did your instructor perhaps
mention a
link to Epstein-Barr virus? |
"Lymphoepithelioma" |
Is it a rounded mass on the true vocal cord? Is the patient
perhaps a
singer, a teacher, and/or a drill sergeant? |
Laryngeal polyp |
Is it a wart-like, non-invasive tumor on the vocal cord? Did the
instructor perhaps mention a link to human papillomavirus? Are
they
perhaps multiple, and did they obstruct a child's airway? |
Laryngeal papilloma |
Is it an invasive, cauliflower-like mass on the mucosa of any
portion
of the larynx? Histologically, is it malignant? |
Laryngeal carcinoma
NOTE: Most of these are squamous cell carcinomas. |
Is it a painful ulcer, lasting a few days, somewhere on the oral
mucosa (not the vermilion border of the lip), perhaps related to
minor
trauma or stress, but not to more serious illness? Do you
recognize it
as the familiar "canker sore"?
Or is it a similar ulcer on a mucosal surface from a patient with
Beh€et's disease or Crohn's regional enteritis? |
Aphthous ulcer
NOTE: "Not caused by herpes." |
Is it a blistering eruption on the lip, perhaps at a time of
stress or
sunburn? Do you recognize the familiar "fever blister"?
Is it little blisters and ulcers throughout the mouth of a baby
or
immunosuppressed person? |
Herpes stomatitis |
Is it leukoplakia or erythroplakia of the oral mucosa with
considerable cellular atypia on biopsy?
Is it a cauliflower-like mass or malignant ulcer on the oral or
lip
mucosa? Does biopsy perhaps confirm malignancy? |
Mouth cancer
NOTE: Most of these are squamous cell carcinomas. |
Is it enlarged salivary gland in an adult with dry eyes and dry
mouth?
Does the person perhaps also have rheumatoid arthritis, lupus,
scleroderma, anti-SSA/Ro, anti-SSB/La, and/or B-cell lymphoma?
Is it a biopsy showing major or minor salivary gland with most of
the
acini gone and replaced by a mass of lymphoid tissue, with or
without
germinal centers? |
Sjogren's syndrome |
Is it a round, benign-appearing, shiny, grayish mass in a
salivary
gland?
On microscopy, does it look like cartilage with a variable mix of
primitive stellate myxoid tissue, acini and duct-like structures,
hair
structures, and/or other stuff? |
Pleomorphic adenoma (mixed tumor of salivary gland) |
Is it a round, very soft, brown mass in the parotid gland?
Is it a parotid tumor composed of tall, benign-appearing cells,
strongly eosinophilic and packed with mitochondria? And is there
a
heavy lymphoid infiltrate? |
Warthin's tumor (papillary cystadenoma lymphomatosum) |
Is it a salivary gland, mouth or bronchial tumor that exhibits
both the
keratinization, desmosomes, and/or pearls of a squamous cell
carcinoma,
and the mucin and/or dPAS-positivity of an mucin-producing
adenocarcinoma? |
Mucoepidermoid carcinoma |
Is it a salivary gland tumor composed of well-differentiated
cells,
consistent with salivary acini (eosinophilic, basophilic, or
pale-
staining), but without ducts? |
Acinic cell carcinoma |
Is it a salivary gland, mouth or bronchial tumor with a striking
cribriform (glands-within-glands, i.e., Swiss cheese) pattern?
Do the
cells look pretty much benign? Do you perhaps see perineural
invasion?
And can you perhaps tell that the mucus in the glands stains
slightly
differently from the ground substance of the rest of the
stroma? |
Adenoid cystic carcinoma |
Does the proximal portion of the esophagus terminate abnormally
and/or
communicate abnormally with the trachea or a bronchus? |
Esophageal atresia / tracheo-esophageal fistula |
Is the esophagus abnormally dilated along most of its length, but
without any evidence that the gastroesophageal sphincter fails to
open? |
Megaesophagus Think of Chagas's disease |
Is the esophagus abnormally dilated, but the gastroesophageal
sphincter tightly closed? |
Achalasia |
Is it a fibrous ledge in the upper esophagus? |
Esophageal web |
Is it a fibrous ledge at the level of the squamocolumnar junction
between esophagus and stomach? |
Schatzki's ring |
Is it the proximal portion of the stomach which appears to have
been
pulled up into the thorax by the esophagus? |
Sliding hiatus hernia |
Is it a portion of the stomach that has herniated up into the
thorax
next to the esophago-gastric junction? |
Para-esophageal hiatus hernia |
Is it a portion of the esophageal mucosa which has herniated out
past
the cricopharyngeus muscle? |
Zenker's pulsion esophageal diverticulum
Note: Pseudo-diverticulum |
Is it a portion of the esophageal wall that has been pulled
sideways
into a blind pouch, perhaps by scar contraction in an adherent
tuberculous mediastinal lymph node? |
Traction esophageal diverticulum
NOTE: True diverticulum |
Is it a small tear in the esophageal mucosa, resulting from
severe
retching? Did it perhaps bleed copiously? |
Mallory-Weiss esophageal laceration |
Is it an esophagus with its wall diffusely scarred and thickened,
most
severely near the stomach?
Is it a biopsy of the esophageal mucosa showing some of the
following: |
Gastroesophageal reflux |
Is it a biopsy of the esophageal mucosa showing any columnar
cells in
the surface epithelium? |
Barrett's esophagus |
Is it dilated, thick-walled veins in the mucosa of the distal
esophagus? |
Esophageal varices |
Is it a fungating or ulcerating cancer in the esophagus? Is the
patient perhaps known heavy drinker and heavy smoker? Or is the
patient perhaps known to suffer from Barrett's esophagus? |
Esophageal cancer NOTE: Most are squamous cell carcinoma; in Barrett's mucosa, expect adenocarcinoma
|
Are some of the abdominal viscera in one pleural cavity or the
other,
because part of the diaphragm did not form properly? |
Diaphragmatic hernia |
Is the pyloric muscle much too thick, obstructing outflow from
the
stomach? Is the patient perhaps a 1-month old male infant with
projectile vomiting? |
Pyloric stenosis |
Is the gastric mucosa acutely inflamed? In other words, do you
perhaps see hyperemia grossly and neutrophils in the lamina
propria
microscopically? In bad cases, are there lots of little ulcers
and
bleeding points? |
Acute gastritis |
Has the fundus of the stomach lost the velvety appearance of its
mucosa? On microscopy, do you see the epithelium transformed
into a
nondescript simple cuboidal epithelium, perhaps with atypia?
Does the
patient perhaps have antibodies against parietal cells,
antibodies
against intrinsic factor, pernicious anemia, Hashimoto's disease,
and/or autoimmune Addisonism? |
Type A chronic gastritis |
Is the gastric antrum selectively inflamed? Does the patient
perhaps
have a duodenal ulcer as well? Do you know that the patient
makes
excess stomach acid? Is the antrum infested with
Helicobacter ? |
Type B "hypersecretory" chronic gastritis |
Is the gastric antrum, and perhaps the fundus, involved in a
process
with some or all of the following: ...chronic inflammation; ...atrophy; ...intestinal metaplasia of some type; ...carcinogenesis? And does the process begin on the surface and spread deep into the glands as it progresses? |
Type AB "environmental" chronic gastritis |
Is it a wiggly-looking bacterium adhering to the surface of
antral-type
gastric mucosa (in the antrum, or metaplasia elsewhere in the
gut)?
Are the surfaces of the mucus-producing cells disrupted? |
Helicobacter |
Are the mucosal folds excessively thick grossly and
microscopically?
Does histologic examination show excessive numbers of mucus
cells? Is
there excess mucus production, perhaps leading to protein
wasting? |
M‚n‚trier's hypertrophic gastritis
Or some related condition. |
Is the gastric mucosa abnormally thick and lush, as a result of a
gastrinoma somewhere else inside the patient? Does the patient
(probably) have ulcers and/or diarrhea? |
Zollinger-Ellison syndrome |
Are there several small (ó1 cm) superficial ulcers in the gastric
fundus? Is the patient perhaps under marked physical (burns,
intracranial catastrophe, deadly illness) and/or emotional
stress? Or
did the patient perhaps take a lot of alcohol, tobacco, coffee,
aspirin, or glucocorticoids? |
Acute gastric erosions / acute stress ulcers |
Is it a sharply-demarcated benign ulcer in some portion of the
gut
exposed to peptic juice and perhaps Helicobacter?
If it is an ulcer in the stomach, has scar contraction produced a
radiating pattern of the rugae? |
Peptic ulcer |
Is it one of several small, smooth exophytic growths on the
gastric
mucosa?
Is it a stomach tumor composed primarily of benign-appearing
glands
resembling normal gastric pits? |
Hyperplastic gastric polyp |
Is it an exophytic gastric tumor, microscopically composed of
tubular
or villous glandular structures, perhaps with some dysplasia or
even a
tiny focus of cancer? |
Neoplastic gastric polyp ("adenomatous polyp of the stomach") |
Is it an exophytic and/or ulcerating gastric mass, composed
either of
tall, bizarre columnar cells or large, bizarre polygonal cells or
signet-ring cells?
Is it a stomach with its wall more or less diffusely thickened
("linitis plastica"), with cancer cells singly or in small
clusters
infiltrating through the wall? |
Stomach cancer
NOTE: Most gastric cancers are adenocarcinomas |
Is it a malignant mass in the mucosa of the stomach composed of
monotonous cells with scanty cytoplasm and which do not adhere to
each
other? |
Gastric lymphoma |
Is it a grossly and microscopically benign-appearing stomach
tumor that
takes a silver stain, produced carcinoid syndrome, or is positive
for
neurosecretory granules? |
Gastric carcinoid |
Is it a portion of small intestine with creatures on its brush
border,
presenting crescent shapes in cross-section? |
Giardiasis |
Is it a portion of small intestine with little, round,
basophilic,
acid-fast creatures living in its brush border? |
Cryptosporidiosis
Or some similar organism |
Is it a portion of small intestine with epithelial cells packed
with
clear lipid? Does the patient perhaps have malabsorption and/or
acanthocyte red cells? |
Abetalipoproteinemia |
Is it a portion of small intestine (or perhaps someplace else)
with
large pools of fat plus abundant macrophages loaded with
PAS-positive
bacilli, both in the lamina propria? Does the patient have
malabsorption, and perhaps also arthropathy and/or
encephalopathy? |
Whipple's disease |
Is it a non-neoplastic disease of the small bowel with ulcers
with
their long axes oriented parallel to the long axis of the
bowel? On section, do you see an infiltrate composed primarily of macrophages, with phagocytosis of necrotic debris and normal red cells?
Are there excessive macrophages in other lymphoid tissues of the
body? |
Typhoid fever
Tip: Use a metachromatic stain to see the bacteria! |
Is it a portion of bowel that shows dusky-brown to gangrenous
changes
as a result of thrombosis or other occlusion of the superior
mesenteric
artery? Is it a portion of bowel that showed hemorrhagic necrosis as a result of being trapped in a hernia, in an intussusception, or under an adhesion? Is it a large intestine with dusky-brown to gangrenous changes at the splenic flexure or in the midportion of the rectum ("watershed zones")? Was the patient perhaps in shock, and/or receiving digitalis, norepinephrine, or dopamine?
Is this a mild case in which there is acute inflammation with or
without necrosis (which if present simulates a pseudomembrane)
involving the superficial mucosa? |
Ischemic bowel |
Is it small intestinal mucosa, the only abnormality being
deepened
crypts and absent villi? |
Sprue (including "celiac disease"/ "gluten enteropathy" and
"tropical
sprue")
|
Is it small intestinal mucosa packed with eosinophils? |
Consider food allergy |
Is it small intestinal mucosa with plenty of lymphocytes but no
plasma
cells? |
Agammaglobulinemia
NOTE: You win the sharp-eyes prize if you noticed this! |
Is it a portion of small bowel, or some other portion of the gut
or
large airways, exhibiting several of the following: ...lesions are sharply focal ("string sign", "garden hose segments", and all that); ...some pathology in all three layers of the gut ...fissure ulcers running parallel to the long axis of the gut; ...ulcers resembling the familiar aphthae; ...non-caseating granulomas; ..."creeping fat" growing up around the side of the gut wall; ...fistula formation; ...most common site of involvement is the terminal ileum? |
Crohn's regional enteritis ("terminal ileitis") |
Is it a tough, thin fibrous band connecting two periteonalized
surfaces? |
Peritoneal adhesion |
Is it a mass of mucus and fibrous tissue matting together the
peritoneal surfaces? And are there at least a few cancer cells
in the
mucin? |
Pseudomyxoma peritonei |
Is it a loop of bowel telescoped into itself? |
Intussusception |
Is it a loop of bowel twisted around its mesentery? |
Volvulus |
Is it a birth defect in which a portion of small or large bowel
has no
lumen? |
Atresia of the bowel |
Is it a two-inch true diverticulum of the ileum, two feet
proximal to
the cecum? Does it perhaps contain gastric mucosa? Has it
perhaps
ulcerated or bled or become inflamed? |
Meckel's diverticulum |
Is it a grossly and microscopically benign-appearing intestinal
tumor
that takes a silver stain, produced carcinoid syndrome, or is
positive
for neurosecretory granules? |
Intestinal carcinoid |
Is it a grossly and microscopically benign-appearing tumor of the
bowel? Histologically, is there a mix of normal-appearing
glands,
abundant collagenous stroma, and a tree-like pattern of smooth
muscle?
Does the patient perhaps have dark freckles especially on the
lips? |
Peutz-Jegher type hamartomatous intestinal polyp |
Is it large intestine grossly distended because of lack of
motility,
and thorough examination of the involved wall shows few or no
ganglion
cells? |
Hirschsprung's megacolon |
Is it large intestine grossly distended because of lack of
motility,
and the underlying cause is serious intrinsic disease of the
colon
(i.e., ulcerative colitis, pseudomembranous colitis, bacterial
colitis)? |
Toxic megacolon |
Is the lamina propria of the large bowel packed with macrophages
laden
with brown pigment? Does the patient perhaps recall having used
cascara or rhubarb? |
Melanosis coli |
Is it a portion of large bowel, especially a portion of sigmoid,
with
little blebs sticking out its sides at 120ø from the
mesentery?
Has a portion of the mucosa herniated through the muscularis
propria of
the large bowel? Is there perhaps a big fecalith in the lumen?
Or did
the little tiny artery get scraped and bleed like crazy? |
Diverticular disease of the colon ("diverticulosis")
NOTE: Yes, these are really pseudo-diverticula. |
Has a portion of the mucosa herniated through the muscularis
propria of
the large bowel? And is the surrounding area now a mess of acute
inflammation and scarring? |
Diverticulitis of the colon |
Is it a dilated vein in the hemorrhoidal plexus around the anus?
And
has it been persistently dilated? |
Hemorrhoid |
Is it a large bowel or portion thereof exhibiting most of the
following: ...rectum is most severely involved, and there are no discontinuities; ...the mucosa is ulcerated, with some spared areas appearing like cobblestones; ...the ulcers are superficial, polygonal craters instead of deep longitudinal fissures ...the mucosa is heavily infiltrated with plasma cells; ...some crypts are distended and packed with neutrophils ("crypt abscesses") ...the process is confined to the mucosa except in the most severe cases; ...regenerating mucosa appears as pseudopolyps ("inflammatory polyps"); ...except perhaps for "backwash ileitis", no other portion of the gut is involved; ...there are no granulomas; ...nothing looks like an amoeba, and the shigella culture came back negative; ...is there perhaps some dysplasia, or even a frank cancer? |
Ulcerative colitis NOTE: "Crypt abscesses", while usually present, are by no means pathognomonic
NOTE: Shigella and some other infections can produce a very
similar
picture. |
Is it a large intestine with a greenish pseudomembrane covering
its
inner surface, at least in patches?
Is it a microscopic picture of large intestine with the upper
half of
the mucosa replaced in patches by tufts of fibrinous and necrotic
debris? |
Pseudomembranous colitis
NOTE: Ischemic colitis can look quite similar. Clinical
correlation
(Clostridium difficile , antibiotic use) required! |
Is it a portion of large intestine with an extra dense,
collagenous
layer underneath the epithelium? And are the crypts basically
normal,
without crypt abscesses? |
Collagenous colitis |
Is it an extensively ulcerated colon, with ulcers widening just
above
the muscularis mucosae, where they stop ("Erlenmeyer flasks")?
Are there large, round, dPAS-positive, multinucleate,
erythrocyte-
eating blobs that could be amoebas? |
Amebic colitis
NOTE: Masses of granulation tissue in the cecum in this disorder
are
amebomas |
Is it a severe inflammatory and perhaps necrotizing lesion of the
bowel of a newborn, perhaps a premature baby? And was the child
perhaps not breast-fed? |
Necrotizing enterocolitis |
Is it a portion of colonic mucosa with several tiny nodules that
look
like rice grains, and no other abnormality?
Is it a biopsy of one such lesion, showing mucus epithelial cells
of
variable heights, imparting a scalloped or sawtooth appearance to
the
crypts? |
Hyperplastic polyp of the colon |
Is it a pedunculated ("berry on a stem") or sessile ("bump"),
benign-
appearing lesion on the colonic mucosa? And does microscopy show
epithelial cells that: ...are too tall for their width; ...have large, elongated nuclei, with too little cytoplasm; ...make very little mucin? |
Adenoma ("adenomatous polyp") of the colon
NOTE: Look at the architecture to distinguish the villous adenoma
from
the tubular adenoma. Both can turn malignant; the villous
adenoma is
more worrisome. |
Is it a colonic polyp, typically from a child, with abundant
stroma and
a pattern of normal-appearing glands? (I.e., is this a
hamartoma?) |
Juvenile colon polyp |
Does the colon contain hundreds of adenomatous polyps? Has it
been
perhaps removed by a savvy physician to prevent cancer? |
Familial adenomatous polyposis coli NOTE: Anti-oncogene deletion syndrome.
Variants:
Turcot's syndrome: F.A.P. plus brain tumors |
Is it an exophytic (cauliflower), endophytic (ulcer), and/or
diffusely-infiltrating (napkin-ring, radiologist's apple-core)
lesion
of the colon?
Microscopically, is it an adenocarcinoma composed of tall,
basophilic
cells with elongated nuclei? Or is it perhaps a more anaplastic
adenocarcinoma, or even an infiltrating signet-ring
adenocarcinoma? |
Adenocarcinoma of the colon ("colon cancer") |
Is it an appendix that is obviously acutely inflamed and perhaps
ruptured, gangrenous, and so forth?
Is it a histologic section of appendix, and neutrophils are
present? |
Acute appendicitis |
Is it an appendix bearing a yellow tumor, without other
pathology? If
you have additional information, does it suggest carcinoid? |
Appendiceal carcinoid |
Is it an appendix that is distended with mucus? |
Mucocele of the appendix
NOTE: This can result either from distention following
obstruction, or
from a mucus-producing adenoma or adenocarcinoma. |
Is it a retroperitoneum with an overgrowth of very dense
connective
tissue, eventually compromising the ureters? Did the patient
perhaps
take a lot of ergot? |
Retroperitoneal fibrosis ("sclerosing retroperitonitis") |
Is it a section of liver parenchyma with most or all of the
following: ..."lobular disarray" (i.e., you do not see the usual separate liver plates) ...a lymphocytic infiltrate among the hepatocytes, or at least in the portal areas; ...hydropic change ("ballooning degeneration") ...single-cell necrosis ("apoptosis", "Councilman-body formation"); ...extra Kupffer cells, with some perhaps packed with lipofuscin indicating recent hepatocyte necrosis; ...necrosis of small groups of cells, typically disappearing ("dropout necrosis"), with the reticulin, sinusoids and Kupffer cells collapsing together here? |
Viral-type hepatitis Think of acute hepatitis A, B, C, D, or E, or yellow fever
Also consider autoimmune "lupoid" hepatitis, Wilson's disease, or
drug
effect (remember isoniazid hepatitis, alpha-methyldopa hepatitis,
others). |
Is it a gross or microscopic section of liver, with the lobular
architecture more or less gone, and divided instead by fibrous
bands
into well-defined nodules? |
Cirrhosis
For the likely cause, check the size of the nodules, and look for
additional hints. |
Is it a cirrhotic liver with nodules mostly less than 3 mm
across? |
Micronodular cirrhosis Think first of alcoholism, then of other processes that involved lobules more or less uniformly, i.e., Wilson's disease, iron overload ("hemochromatosis"), primary biliary cirrhosis, methotrexate toxicity, or alpha-1 protease inhibitor ("antitrypsin") deficiency |
Is it a cirrhotic liver with nodules greater than 3 mm
across? |
Macronodular cirrhosis
Think first of autoimmune "lupoid" hepatitis or hepatitis B, C,
or D,
because these processes involved lobules non-uniformly. Remember
that
cirrhosis from any cause may progress to large nodules when it
reaches
the end-stage of "postnecrotic cirrhosis". |
Is it a cirrhotic liver with extreme scarring, no matter how big
the
nodules are? |
Postnecrotic cirrhosis
NOTE: This is a dumb name for the end-stage of cirrhosis from any
cause. |
Is it a pale, flabby, shrivelled liver with a wrinkled capsule?
Did
the patient die, or is the patient near death?
Is it a section of liver with dropout or apoptosis of most of the
liver cells? If there are live cells, are they proliferating
from the
tiny bile ducts? |
Massive hepatic necrosis ("acute yellow atrophy")
Think of acute hepatitis B, C, or D, amanita toadstool poisoning,
carbon tetrachloride toxicity, acetaminophen overdose, halothane
idiosyncracy |
Does it look like massive hepatic necrosis but not quite so bad,
and
patient is perhaps not dead or near death? |
Sub-massive hepatic necrosis
Think of the same causes as for massive hepatic necrosis |
Is it a portion of liver with a heavy portal infiltrate, composed
primarily of lymphocytes? Is the patient (probably) known to be
six-
months post the onset of viral hepatitis, and still has elevated
serum
transaminases? Do you see NO tendency of the infiltrate to spill
into
the liver parenchyma? If there is any hepatitis-like change in
the
parenchyma, do you at least see NO "piecemeal necrosis" of groups
of
cells at the limiting plate? And finally, are you confident the
patient does not have lymphoma or Hodgkin's disease? |
Chronic persistent hepatitis Think of a person recovering from hepatitis B.
The prognosis is generally good. |
Is it a portion of liver with a heavy portal infiltrate, composed
largely of lymphocytes? Does the infiltrate tend to spill into
the
liver parenchyma? And do you see at least groups of a few cells
undergoing apoptosis or dropout next to the limiting plate
("piecemeal
necrosis")? And do you perhaps even see bands of necrosis
running from
portal area to central vein ("bridging necrosis")? |
Chronic active hepatitis Think of hepatitis B, C, or D, autoimmune "lupoid" hepatitis, Wilson's disease, alpha-1 protease inhibitor ("antitrypsin") deficiency, or drug effect.
The prognosis is generally bad. The process leads to
cirrhosis. |
Is it a bile duct or canaliculus distended by green-brown
material? Is it a mass of green-brown material surrounded by a ring of hepatocytes?
Are there perhaps some nearby Kupffer cells that have
phagocytized
bile? Do you perhaps see "feathery degeneration" of hepatocytes
laden
with bile salts? |
Bile plug / bile lake
Think of some cause of intrahepatic (alcoholism, hepatitis,
cirrhosis,
tumor) or posthepatic (gallstone, tumor) bile duct
obstruction |
Is he or she a person with a mild (2-6 mg/dL) unconjugated
hyperbilirubinemia and no other problem? Does this level double
when
the person fasts for a few days? If somebody actually biopsied
the
liver (and I'm not recommending this), is it normal? |
Gilbert's non-disease |
Is he or she a person with a mild (2-6 mg/dL) conjugated
hyperbilirubinemia and no other problem? And is the liver dark
brown
grossly, and are the hepatocytes laden with brown pigment? |
Dubin-Johnson non-disease
NOTE: No pigment? Rotor non-disease |
Do 75% or more of the hepatocytes contain Prussian-blue stainable
iron? Is there stainable iron in the bile duct epithelium? Are the spleen, pancreas, adrenals, heart, and duodenum a rusty color, with abundant stainable iron on microscopy?
For any of the above, is the patient's skin perhaps a curious
bronze-
brown color? Is there perhaps cirrhosis? Is there perhaps
diabetes?
Is there perhaps arthritis worst in the knuckles? Is there
perhaps
loss of libido? Is there perhaps a cardiac rhythm disturbance?
Is the
transferrin saturation (serum Fe/TIBC) greater than 82% (or at
least
high)? |
Severe iron overload, probably primary hemochromatosis
NOTE: Also ask about previous transfusions for insufficient red
cell
production |
Are the Kupffer cells packed with hemosiderin? |
Chronic hemolysis |
Are the Kupffer cells packed with a pigment that looks like
hemosiderin but does not take the Prussian blue stain? |
Malaria |
Is it liver from a child with lobular disarray and formation of
hepatocyte syncytia (giant cells) of hepatocyte origin? |
Neonatal hepatitis
NOTE: Many causes |
Is it neonatal or adult hepatitis, perhaps with widespread
necrosis,
with large, eosinophilic inclusions in the hepatocyte nuclei?
In the neonate, is there widespread hepatic necrosis as well as
necrosis of the brain and adrenals? |
Herpes simplex hepatitis |
Is it a liver with microvesicular steatosis? Did it come from a
child
with cerebral edema following a mild viral-type illness? And was
blood
ammonia preposterously high? And did electron microscopy perhaps
show
widespread severe damage to the body's mitochondria? |
Reye's syndrome |
Is it a liver containing random grooves across its surface? |
Hepar lobatum
NOTE: Textbooks cite congenital syphilis with deep gummas and
scar
contraction; much more often today, this is a mere congenital
curiosity |
Is it a liver with a series of "rib" grooves on its right
diaphragmatic surface? |
Costal grooves
NOTE: Lots of emphysema patients develop them. |
Are the portions of the sinusoids closest to the central veins
distended with blood? Are the hepatocytes dead or dying around the central vein ("centrilobular necrosis", "ischemic hepatitis") without a history of poisoning? Are the Kupffer cells in the central area packed with hemosiderin (from broken-down red cells) and lipofuscin (from dead hepatocytes) and bile (couldn't be processed in the hypoxic environment)?
Is the patient in shock or right-sided heart failure, and the
underlying problem is not liver disease? |
Congested liver / hypoxic liver
NOTE: These usually occur together. Congestion doesn't damage
the
liver |
Is there a bit of scarring just around the central veins, perhaps
enough to produce "pigskin" dimples on the liver surface? And
has the
patient had problems with right heart function (notably,
tricuspid
insufficiency) for a while? |
Cardiac hepatic sclerosis NOTE: Usually a non-problem. I bet you never see "cardiac cirrhosis", with central-central bridging.
|
Is it a blue or pale wedge-shaped area in a liver? Is it perhaps
atrophic? And has either a portal vein or hepatic artery branch
been
occluded? |
Zahn hepatic infarct NOTE: Dual blood supply prevents necrosis, and "infarct" is a figure of speech. The blue color is from slow blood flow (how?) |
Is the liver very congested, and you see a gross thrombus in a
large
hepatic vein, and/or a microscopic thrombus in a central vein?
And
does your patient perhaps have polycythemia vera, or is pregnant,
or
has hepatocellular carcinoma? |
Budd-Chiari syndrome |
Is it a photomicrograph of congested liver, with veins showing
greatly
thickened walls (check the reticulin or elastic stains), perhaps
with
little thrombi? |
Hepatic veno-occlusive disease |
Are the hepatocytes dead or dying, worst around the central
vein? |
Centrilobular hepatic necrosis
Think of ischemia, carbon tetrachloride, chloroform. Lowest
oxygen
tension in the liver makes these cells most vulnerable. |
Are the hepatocytes dead are dying, worst in the midzonal area?
Do you
see Councilman bodies but not much inflammation? |
Midzonal hepatic necrosis / yellow fever
Nobody knows why. |
Are the hepatocytes dead or dying, worst in the periportal
("peripheral) areas? |
Peripheral hepatic necrosis / periportal hepatic necrosis
Think of phosphorus or some other exotic poisoning; if there are
little fibrin thrombi, and bleeds all over the liver, it's
probably
eclampsia. Bad things in the blood reach these cells first. |
Is it a hepatocyte with a "ground glass" homogeneously-staining
cytoplasm? Do you perhaps have a picture showing it staining
positive
with orcein? |
Hepatitis B carrier or Hepatitis B chronic liver disease |
Is it obvious suppuration along the biliary tree?
Is it a bile duct with two or more neutrophils in its lumen? |
Acute cholangitis |
Is there a lymphocytic infiltrate concentrated around the bile
ducts in
the portal triads? And is there some clinical evidence of
cholestasis,
but no other abnormal anatomy? |
Pericholangitis |
Are certain bile ducts, inside and/or outside of the liver,
narrowed by
chronic inflammation and dense scarring? And there has been no
biliary
surgery? Do the bile ducts perhaps look like a string of white
beads?
And does the patient perhaps also have ulcerative colitis? |
Primary sclerosing cholangitis |
Is it pus in a confined space in the liver? |
Liver abscess
NOTE: Nothing subtle. The underlying cause is usually ascending
cholangitis from obstruction. |
Is it an area of necrosis in the liver with little or no
inflammatory
reaction? And if you look (or have a dPAS stain), do you see
amebas? |
Amebic liver abscess |
Is it fatty change in the liver, and most of the cells have a
single
fat vacuole? |
Macrovesicular steatosis
Think of alcoholism, ischemia, methotrexate toxicity or other
drug
effect, Wilson's disease, galactosemia, other rare metabolic
kinks,
hepatitis C |
Is it fatty change in the liver, and most of the cells have
several
small fat vacuoles? |
Microvesicular steatosis
Think of ischemia, drug effect, Reye's syndrome, pregnancy,
outdated
tetracycline, heavy aspirin use, rare metabolic kinks, hepatitis
C |
Is it fatty change in the liver, without inflammation, Mallory's
alcoholic hyaline, neutrophils, cell necrosis, or cirrhosis? And
is
the patient known to overindulge in alcohol? |
Alcoholic fatty liver
NOTE: Liver function and serum enzymes may be very abnormal, but
this
is NOT cirrhosis, and should be reversible upon abstinence. |
Is it a liver with fatty change plus cell necrosis, neutrophils,
and
Mallory's alcoholic hyaline? And is cirrhosis not (yet) present?
And
is the patient known to overindulge in alcohol? |
Alcoholic hepatitis
NOTES: (1) Liver function and serum enzymes will be very
abnormal, but
this is not cirrhosis, and should be reversible upon abstinence.
(2)
Drug effects and Wilson's disease can give identical
histology. |
Is it a cirrhotic (micronodular or massively-scarred
postnecrotic)
liver in a patient who is or was known to overindulge in alcohol,
which
you assume to be the cause? Are alcoholic fatty change or even
alcoholic hepatitis perhaps also present (if the patient was
recently
drinking, that is)? |
Alcoholic ("Laennec's") cirrhosis |
Is it a liver showing changes similar to alcoholism, acute viral
hepatitis, or chronic active viral hepatitis, but special stains
for
copper (rhodanine, rubeanic acid) show abundant copper deposition
in
hepatocytes? Does the patient have a Kayser-Fleischer ring in the cornea?
Does the patient perhaps have neurologic problems and/or
hemolysis in
addition to / instead of obvious liver problems? |
Wilson's disease
NOTE: Don't goof on this one. |
Are there variably-sized round globules of dPAS-positive material
inside hepatocytes? Is there perhaps hepatitis or cirrhosis? |
Alpha-1 protease inhibitor ("antitrypsin") deficiency |
Is it a liver with lymphocytes, histiocytes, and plasma cells
surrounding and apparently destroying the portal bile ducts? Are
the
ducts either gone or proliferating bizarrely? Is there visible
cholestasis? Has the process perhaps progressed with fibrosis
toward,
or to, a true cirrhosis? Is there perhaps also some granuloma
formation, some Mallory's hyaline, or some local excess of
copper? |
Primary biliary cirrhosis |
Is it fibrosis progressing to cirrhosis as a result of biliary
obstruction? Are the bile ducts still intact? |
Secondary biliary cirrhosis
|
Is it a liver with widespread scarring, with many plasma cells in
the
scars? |
Congenital syphilis
NOTE: You'll probably never see this today. |
Is it a sharply-circumscribed, homogeneous-looking red or blue
blotch
in the liver?
Is it a vascular hamartoma in the liver on microscopic
examination? |
Hemangioma of the liver
Future surgeons: Don't biopsy. |
Is it a circumscribed bump (typically yellow) in the liver, with
a
central, star-shaped scar?
Microscopically, does it look like a nodule of cirrhosis plus
fatty
change, in an otherwise-normal liver? Is the patient perhaps
(but not
necessarily!) a man taking anabolic steroids, or a woman taking
the
oral contraceptive pill? |
Focal nodular hyperplasia of the liver
NOTE: "Fool's cirrhosis" |
Is it circumscribed bump (typically yellowish) in the liver, with
prominent blood-engorged sinusoids?
Microscopically, is there no or mild cellular atypia? Is the
patient
perhaps (but not necessarily!) a man taking anabolic steroids, or
a
woman taking the oral contraceptive pill? |
Liver cell adenoma ("hepatic adenoma") |
Is it a circumscribed white bump in the liver, microscopically
with
many little bile ducts in fibrous tissue and not much else? |
Bile duct adenoma ("von Meyenberg complex"; "bile duct
hamartoma") |
Is it a variegated red, yellow, green, brown, and/or white mass,
arising singly or multifocally in the liver, particularly in a
setting
of hepatitis B and/or iron overload and/or exposure to aflatoxin
mold
in a poor person's diet and/or anabolic steroid use? Is it an apparent primary malignancy of the liver that shows a tendency, grossly or microscopically, to invade blood vessels? Is it a cancer composed of trabecular, rings, or sheets of cells that look like hepatocytes? Do they perhaps contain Mallory's hyaline and/or à1-protease inhibitor globules? Is it a cancer, anywhere in the body, that produces bile?
Is it "normal liver, no portal areas identified" obtained from a
lung
biopsy? And the clinicians swear they hit the lung mass, not the
liver? |
Hepatocellular carcinoma ("hepatoma")
NOTE: You can also see Mallory's hyaline in occasional lung
adenocarcinomas. |
Is it a single mass in a non-cirrhotic liver? Microscopically,
is it
composed of plates of hepatocytes separated by sheets of
collagen? |
Fibrolamellar hepatocellular carcinoma |
Is it a childhood liver cancer composed of malignant hepatocytes,
perhaps with an admixture of other mesenchymal elements? |
Hepatoblastoma |
Is it a desmoplastic adenocarcinoma arising in the liver? Are
the
cells perhaps mucin positive but without anything to suggest
hepatocyte differentiation? |
Cholangiocarcinoma
NOTE: These tumors will never produce bile. |
Is it a mixed cancer in the liver, composed of both
hepatocellular
carcinoma and cholangiocarcinoma? |
Mixed hepatocellular carcinoma - cholangiocarcinoma |
Is it a mass of bloody nodules in the liver? And
microscopically, do
you see cords of polygonal cells making poorly-defined vascular
channels, and perhaps some metaplastic bone marrow? Has the
patient
perhaps been exposed to vinyl chloride monomer? |
Angiosarcoma of liver |
Is it tumor nodules in an otherwise-normal liver, the larger ones
bearing a central dimple ("umbilication")? |
Metastases to the liver |
Is the patient a baby with cholestatic jaundice due to failure of
portions of the intrahepatic and/or extrahepatic bile ducts to
form
lumens? |
Biliary atresia |
Is it a gallstone that is mostly yellow?
Is it a large solid common gallstone? |
Cholesterol gallstone |
Is it a gallstone that is mostly black, with a bumpy surface?
And is
it small, under 5 mm or so? And does the patient perhaps have
longstanding intramedullary (megaloblastic anemia, thalassemia)
or
intravascular (hemoglobinopathy, spherocytosis) hemolysis? |
Bilirubinate gallstone |
Is it bile that is so pasty-thick with suspended micro-particles
that
it can plug things? |
Biliary sludge |
Is the gallbladder acutely inflamed, with neutrophils in the
lamina
propria as a minimum? Is there also cholelithiasis? |
Acute cholecystitis |
Has the entire gallbladder undergone dystrophic calcification
after a
bout of acute cholecystitis? |
Porcelain gallbladder |
Are there lots of little yellow flecks (groups of
cholesterol-laden
macrophages) among the mucosal folds of the gallbladder? Do they
remind you of the seeds on a strawberry? |
Cholesterolosis of the gallbladder ("strawberry gallbladder") |
Is the gallbladder laden with opalescent, mucoid fluid? Is the
outlet
occluded by a stone or by scar? |
Hydrops of the gallbladder |
Is it a gallbladder with several of the following: ...hyperplastic smooth muscle; ...scarring of the lamina propria; ...scarring of the serosa; ...pseudodiverticula, in which the mucosa herniates into or through the muscle ("Rokitansky-Aschoff sinuses") ...an inflammatory infiltrate with lymphocytes? |
Chronic cholecystitis |
Is it an exophytic, ulcerating, or infiltrating cancer of the
gallbladder? Does the patient perhaps have gallstones too?
Microscopically, is it composed of malignant glandular or
glandular-
and-squamous elements? |
Adenocarcinoma of the gallbladder |
Is it a malignant tumor of the bile ducts composed of glandular
elements? Does the patient perhaps have infestation with the
liver
fluke, or suffer from ulcerative colitis? |
Adenocarcinoma of the bile ducts NOTE: No relationship to gallstones |
Is it a bile duct adenocarcinoma at the junction of the right and
left
hepatic ducts? |
Klatskin tumor |
Is it a malignant tumor of glandular origin at the ampulla of
Vater? |
Periampullary adenocarcinoma
NOTE: Consider doing a Whipple procedure! You've got a good
chance of
cure if tumor is localized. |
Are the two portions of the pancreas inappropriately wrapped
around the
duodenum? |
Annular pancreas |
Is it a pancreas with atrophy and loss of the acini, and viscous
plugs
in the ducts? |
Cystic fibrosis |
Is it a pancreas with more or less homogeneous atrophy and loss
of the
acini, and perhaps scarring of the interstitium, and this is not
cystic
fibrosis? |
Obstructive pancreatic atrophy |
Is it a pancreas that is transformed into a mess of bloody,
necrotic
stuff?
Microscopically, do you see hemorrhage, necrosis, fat necrosis,
and
acute inflammation? |
Acute hemorrhagic pancreatitis
Ask about alcoholism, trauma, common duct stone or sludge |
Is it a pancreas with uneven atrophy and loss of acini, with
impressive scarring? Are there perhaps protein or calcific blobs in the surviving ducts (suggesting alcoholism)?
And are you confident that no "acinus" or "duct" contains one
nucleus
more than four times bigger than another in the same structure,
and
that you see no mitotic figures, and that you see no obviously
incomplete "acini" or "ducts"? |
Chronic pancreatitis
NOTE: Misnomer. This is scarring from old damage. |
Is it a hollowed-out region in the pancreas or surrounding fatty
tissues, or perhaps even the lesser sac, lined by scar tissue,
with no
inner epithelial layer? |
Pancreatic pseudocyst |
Is it an obvious cancer in the pancreas, composed of cells of
glandular origin? Could it be a pancreatic scar, but there are "acini" or "ducts" which are incomplete or which contain one cell with a nucleus four times larger than another in the same structure, or you see mitotic figures?
And does the patient perhaps have unexplained depression and/or
unexplained venous thrombosis? |
Pancreatic adenocarcinoma / "cancer of the pancreas" |
Is it an islet of Langerhans packed with eosinophils? |
Child of a diabetic mother |
Is it an islet of Langerhans packed with lymphocytes? |
Type I diabetes, early |
Is it a section of pancreas that should contain islets, but
doesn't? |
Type I diabetes, late
NOTE: The best place to find lots of islets is in the tail of the
normal pancreas. |
Is it an islet of Langerhans that contains abundant fibrous
tissue
and/or amyloid?
Is it a section of pancreas that contains some oversized islets?
And
does this surprise somebody, because the patient is diabetic? |
Type II diabetes |
Is it a sharply-circumscribed, round nodule in the pancreas?
Does it have the histology of a very large islet of Langerhans,
perhaps with a collagenous and/or amyloid stroma? And is your
instructor perhaps showing you an immunoperoxidase stain for some
endocrine hormone? |
Islet cell adenoma
NOTE: Some of these will turn out to be cancers. This is pretty
much
unpredictable. |
Is it an islet cell adenoma, and does it stain for insulin and/or
is
the patient suffering from Whipple-triad hypoglycemia and/or has
the
patient become massively obese recently? |
Insulinoma / beta cell adenoma |
Is it lots of little clumps of endocrine-looking cells in the
pancreas, especially near the ducts? Do they stain positive for
insulin? Is the patient suffering from fasting hypoglycemia? |
Nesidioblastosis |
Is it an islet-cell adenoma, and does it stain for glucagon
and/or does
the patient have a sore tongue and/or necrotizing skin
lesions? |
Glucagonoma / alpha cell adenoma |
Is it an islet-cell adenoma, and does it stain for gastrin and/or
does
the patient have Zollinger-Ellison syndrome with lots of stomach
ulcers
and diarrhea? |
Gastrinoma
NOTE: Ask about multiple endocrine neoplasia type I (Wermer's
MEN-
I) |
Is it an islet-cell adenoma, and does it stain for vasoactive
intestinal polypeptide and/or does the patient have watery
diarrhea and
achlorhydria? |
VIPoma |
Is it an islet-cell adenoma, and does it stain for
somatostatin? |
Somatostatinoma / delta cell adenoma |
Is he or she a patient with hematuria of glomerular origin (i.e.,
perhaps your found a red cell cast in the urine)? And does the
patient also have azotemia, hypertension, oliguria, and mild
edema? |
Nephritic syndrome ("nephritis") |
Is he or she a patient with heavy proteinuria of glomerular
origin
(ò3.5 gm per day for an adult, selective or nonselective), plus
the
expected hypercholesterolemia, hypoalbuminemia, and generalized
edema? Is the kidney grossly yellow at autopsy due to lipid accumulation in the proximal tubules? Are there "lipid casts" in the renal tubules or urine?
Regardless of what else is wrong, are most of the foot processes
obliterated on electron microscopy? |
Nephrotic syndrome NOTE: Dumb name!
Think of: |
Is he or she a patient with nephritic syndrome who is taking a
rapidly-downhill course?
On biopsy, are there fibrinous-proliferative crescents in ò80% of
glomeruli? |
Rapidly-progressive glomerulonephritis |
Is he or she a patient who is wasting something into the urine
because
of proximal tubular failure? |
"Fanconi syndrome"
NOTE: Terminology is loose here. |
Is he or she a patient who is unable to concentrate urine well
(i.e.,
complains first of nocturia)? |
Renal medullary dysfunction |
Is he or she a patient with oliguria, azotemia, and isosthenuria
following either: ...ingestion of a tubular poison (mercury, gentamicin, many others); ...an episode of hypotension; ...an episode of massive hemolysis or rhabdomyolysis ...a big dose of non-steroidal anti-inflammatory drugs?
Is this a section of kidney with several of the following: |
Acute tubular necrosis / "acute renal shutdown" / "shock kidney"
/
"vasomotor nephropathy"
NOTE: Other names exist |
Is he or she a patient with the clinical picture of acute renal
tubular necrosis, and you see red pigment casts (hemoglobin or
myoglobin) in the tubules? |
Pigment nephropathy |
Is this a patient with hepatic failure, dilute urine, and bile-
stained casts in the renal tubules? |
Hepatorenal syndrome
NOTE: The morphology doesn't really define this poorly-understood
process. |
Is this a newborn with some or all of one or both kidneys
composed of
irregular cysts and fibrous tissue, as a result of failure of the
blastema to obtain proper drainage? Is it a portion of one kidney found to exhibit similar changes in an older person?
Is it a mess of fibrous tissue, cysts, and perhaps cartilage,
bone,
and/or muscle where kidney tissue ought to be? |
Renal cystic dysplasia
NOTE: This is not polycystic kidney, but a sporadic birth
defect. |
Is it a pair of kidneys that began developing cysts in youth, and
were
gradually transformed into two huge cystic masses by later middle
age? |
Autosomal dominant polycystic kidney disease / "adult polycystic
kidney" |
Is it a pair of massively-enlarged, smooth-surfaced white kidneys
in a
newborn, with long, narrow cysts arranged radially? |
Autosomal recessive polycystic kidney disease / "infantile
polycystic
kidney"
|
Is it a few dilated distal portions of collecting ducts, and the
patient seems none the worse or perhaps developed a stone here,
or got
an infection, or has hematuria, or complains of back pain? |
Medullary sponge kidney
NOTE: This is not polycystic kidney. Nobody knows the cause. |
Is it a bunch of cysts in the medulla and at the corticomedullary
junction, and the patient has isosthenuria and eventually renal
failure? |
Medullary cystic disease / nephronophthisis
NOTE: Several hereditary disorders. |
Is it a single cyst (or a very few cysts) on a kidney with
nothing else
wrong except perhaps small-vessel disease? |
Simple renal cyst |
Is it a kidney that failed years ago, and the patient has been
kept
alive on dialysis or with a transplant? And has the kidney
developed a
mess of cysts, with scars and/or oxalate crystals and/or little
yellow
tumors? |
Acquired dialysis cystic disease / trans-stygian kidney
NOTE: Dialysis isn't the cause. This is the inexorable
progression of
the end-stage kidney. |
Is it a pair of kidneys fused at their lower poles? |
Horseshoe kidney
|
Is it an intensely-eosinophilic, more-or-less round blob in a
sick
glomerulus? |
Hyalinosis lesion
Think of FSGS / hyperfiltration lesion and/or diabetes.
Hyalinosis is
supposed to be a marker for hyperfiltration from any cause. |
Are the glomeruli diffusely hypercellular, maybe with 5 or more
neutrophils per glomerulus, and the hypercellularity is
sufficient to
compromise the capillary lumens? Does immunostaining for IgG and C3 give a coarsely-granular, lumpy- bumpy pericapillary pattern? Does electron microscopy show large, unevenly-spaced subepithelial deposits?
And the patient probably has nephritic syndrome, and you probably
see
some red cells in the tubules? |
Diffuse proliferative glomerulonephritis
Think of post-streptococcal disease, deep bacterial infection,
(remember bacterial endocarditis), bad (WHO IV) lupus |
Is it rapidly-progressive (i.e., crescentic) glomerular disease,
and do
you have either of the following: ...positive anti-GBM antibodies in a significant titer, performed by a competent lab; ...linear fluorescence for IgG along the glomerular basement membrane;
|
Rapidly-progressive glomerulonephritis type I (anti-GBM
disease)
NOTE: "Goodpasture's disease" is anti-GBM disease with hemoptysis
because antibodies also attack lung. |
Is it rapidly-progressive (i.e., crescentic) glomerular disease,
and do
you see either: ...non-linear staining on immunofluorescence; ...immune deposits on electron microscopy? |
Rapidly-progressive glomerulonephritis type II (bad immune
complex
disease) |
Is it rapidly-progressive (i.e., crescentic) glomerular disease
with: ...negative immunofluorescence; ...positive anti-neutrophil cytoplasmic antibody disease?
Is there perhaps also focal-segmental necrosis (which is unusual
in
other forms of RPGN) and/or a systemic vasculitis syndrome? |
Rapidly-progressive glomerulonephritis type III (Wegener's
granulomatosis / polyarteritis) |
Is it a glomerulus with its basement membrane diffusely
thickened, and
the patient doesn't have diabetes? Does dPAS or silver staining of the glomerulus show spikes projecting upward from the GBM? Does immunofluorescence show a finely-granular pericapillary pattern of immune complex deposition? Does electron microscopy show small, evenly-spaced subepithelial deposits?
And the patient probably has heavy nonselective proteinuria
leading to
the nephrotic syndrome? |
Membranous glomerulopathy Think of lupus (WHO V), chronic hepatitis B infection, chronic pyelonephritis, many others. Most cases remain idiopathic.
There's no inflammation, but many people insist on calling this
something "-itis". |
Is it a kidney with glomeruli that look normal by light and
immunofluorescence, and show only loss of foot processes by
electron
microscopy?
Is the patient probably a child (or an adult with Hodgkin's) with
mild
nephrotic syndrome and selective proteinuria? |
Minimal change glomerulopathy ("lipoid nephrosis", "nil
disease") |
Is it a kidney with glomeruli that are unusually large, exhibit
focal
(i.e., some glomeruli are involved) and segmental (portions of
glomeruli are involved) sclerosis (i.e., too much mesangial
matrix /
basement membrane, obliterating capillary loops)? And is the
immunofluorescent picture nonspecific (i.e., just a little IgM
and C3
in the sclerotic areas, as you can see in any scar?) And are all
the
foot processes lost on electron microscopy?
And does the patient have nephrotic syndrome with nonselective
proteinuria? |
Focal-segmental glomerulosclerosis ("FSGS")
NOTE: This infamous lesion is often idiopathic, but can result
from
heroin abuse, HIV infection ("AIDS glomerulopathy") or a few
glomeruli
working overtime because the others are shut down
("hyperfiltration").
You'll see some FSGS in any end-stage kidney. |
Is it a glomerulus with most or all of the following: ...a cloverleaf accentuation of the lobular architecture; ...splitting (reduplication) of the basement membrane ("tram tracks"; silver stain and dPAS show this well); ...irregular granules in immunofluorescence; ..."mesangial cells invading the capillary loops" on electron microscopy.
And is the patient probably a child with both hematuria and heavy
proteinuria? |
Membrano-proliferative glomerulonephritis type I /
mesangiocapillary
glomerulonephritis type I |
Is it a glomerulus with splitting (reduplication) of the basement
membrane ("tram tracks"; silver stain and dPAS show this well) by
an
electron-dense deposit which stains negative for immunoglobulin
and
strongly positive for C3? Is the deposit metachromatic, and
stains
brown with silver?
And is the patient probably a child with both hematuria and heavy
proteinuria? |
Membrano-proliferative glomerulonephritis type II /
mesangiocapillary
glomerulonephritis type II / dense deposit disease |
Is it a kidney with glomerular proliferation, perhaps segmental,
perhaps with some scarring? And is there primarily a mesangial
deposition, primarily of IgA?
And is the patient probably a young person with some degree of
hematuria? |
IgA nephropathy ("Berger's disease") |
Is he or she a patient with some or all of the following: ...bad IgA nephropathy, perhaps with some segmental necrosis and/or crescents; ...vasculitis, with predominantly IgA in the vessel walls; ...GI bleeding; ...arthritis; ...purpura? |
Henoch-Sch”nlein purpura |
Is it a kidney with focal-segmental, rather than diffuse-global,
proliferation in the glomeruli? |
Focal-segmental proliferative glomerulonephritis
Think of bacterial endocarditis (first!), IgA nephropathy, lupus
(WHO III); mild versions of other causes of RPGN. |
Is it a kidney with proliferation of mesangial cells (i.e., it's
easy
to count 5 or more nuclei in some mesangial areas), but without
compromise of capillary lumens (until late)? |
Mesangial proliferative glomerulonephritis
Think of IgA nephropathy, mild lupus (WHO II), Zuni nephropathy,
mild
or resolving proliferative glomerulonephritis, mild or resolving
cases
of other glomerular diseases. |
Is it a kidney with variable glomerular lesions and abundant foam
cells? On electron microscopy, is there a basket-weave GBM? And
is
the patient hard of hearing? |
Alport's hereditary nephritis |
Is it a kidney with most of the glomeruli hyalinized really bad,
with
relatively little vascular disease or interstitial scarring? |
Chronic glomerulonephritis
NOTE: This is end-stage glomerular disease. In an end-stage
kidney,
don't expect to be able to determine the exact cause. |
Is it a glomerulus with diffusely thickened GBM (light or
electron
microscopy), even to the point of obliterating the capillary
lumens,
but no immune deposits? Is there perhaps a hyalinosis lesion? Is it a glomerulus bearing a lens-shaped droplet of hyalinosis-like material on the inner surface of Bowman's capsule ("capsular drop")? Is it a glomerulus with both arterioles about equally hyalinized?
Is it a glomerulus with diffusely thickened GBM plus
variably-sized
rounded nodules ("balls") of mesangial matrix material ("nodular
Kimmelstiel-Wilson lesion")? |
Diabetic glomerulopathy
NOTE: Common usage calls these lesions "diffuse" or "nodular"
glomerulosclerosis, depending on the absence or presence of
Kimmelstiel-Wilson lesion. |
Is it an electron micrograph of a glomerulus showing lamellar
storage
product? |
Fabry's disease |
Is it a massive subendothelial deposit visible on electron
microscopy,
taking up much or all of the rim of the capillary? |
Wire loop
Your patient has lupus, bad membrano-proliferative
glomerulonephritis
type I, or cryoglobulinemia |
Is it a solid mass of protein, not a fibrin-platelet thrombus,
plugging a capillary? Is there some kind of glomerular disease
that
goes with it? |
Cryoglobulinemia
NOTE: D'ya know how to test blood for it? |
Is the renal pelvis dilated and inflamed? Are there lots of little abscesses through a greatly swollen kidney? Are there two neutrophils together in a renal tubule?
Is the renal interstitium packed with neutrophils? (And the
glomeruli
are spared, and appear normal?) |
Acute pyelonephritis |
Are the renal papillae necrotic? |
Renal papillary necrosis
Think of diabetes (all papillae equally dead), phenacetin abuse,
very
severe pyelonephritis, sickle cell disease or even trait,
Wegener's
granulomatosis (all show papillae unequally dead). |
Is this kidney acute inflamed and perhaps even shut down,
probably with
some kind of inflammatory infiltrate (neutrophils, eosinophils,
lymphocytes, and/or plasma cells) in the interstitium, but you
cannot
identify a bacterium? |
Acute interstitial nephritis
NOTE: Consider lupus or other immune, drugs, others. |
Is it a kidney with irregular scarring, with broad pitting,
especially
at the poles, suggesting damage from repeated bouts of acute
infection?
And is there some obstructive or reflux-producing lesion, or a
stone,
that could have exacerbated the tendency to infection?
Microscopically, do you see interstitial scarring, perhaps with
lots of
lymphocytes, but with more or less normal glomeruli and vessels?
Do
you perhaps even see an area in which scar contraction has
dilated
cast-filled tubules ("thyroidization")? |
Chronic pyelonephritis
NOTE: Another misnomer. It's scarring from previous infection.
Perhaps bacteria persist. |
Is this a kidney with the microscopic picture of chronic
pyelonephritis, but no history of acute pyelonephritis?
Are there perhaps abundant plasma cells as well, suggesting
autoimmunity? |
Chronic interstitial nephritis
Consider drug effect, anti-tubular basement membrane disease,
lupus,
Sjogren's, many others. |
Did the patient take a non-steroidal anti-inflammatory drug, and
is now
in renal failure, and do you see some or all of the
following: ...fused foot processes; ...acute tubular necrosis; ...papillary necrosis (severe cases)? |
Analgesic nephropathy |
Are there uric acid crystals in the kidney tubules or
insterstitium?
Are there perhaps tophi and/or urate stones? |
Urate nephropathy
Consider gout treated primarily with probenecid, massive tissue
necrosis, others. |
Does the patient have plasma cell myeloma, and as a result, is
there
one or more of the following: ...amyloid B in the glomeruli; ...metastatic calcification; ...casts in the tubules with foreign-body reaction; ...infection? |
"Myeloma kidney" |
Is it a glomerulus that has been obliterated by fibrous tissue,
and
does dPAS or silver staining reveal a shrivelled glomerular tuft,
reduplicated Bowman's membrane, and the remainder of the space
filled
by dense collagen? |
Ischemic end-stage glomerulus
NOTE: The cause was damage to the blood vessels, probably
hypertensive. |
Is this a kidney with most or all of the following: ...finely-granular surface; ...hyalinized arteriolar sclerosis of afferent arterioles with sparing of efferent arterioles; ...concentric intimal fibrosis of the intrarenal arteries; ...many glomeruli hyalinized as a result of chronic ischemia (i.e., shrivelled tuft, urinary space packed with collagen)? And is there a history (maybe, sort-of) of "benign essential hypertension"?
Or did the opposite kidney have renal artery stenosis, and the
patient
had Goldblatt hypertension? (Why the opposite kidney?) |
Hypertensive kidney / "nephrosclerosis" NOTE: "Arterial nephrosclerosis", due to narrowing of big vessels, produces wedge-shaped scars that show better in books than in real life. Ischemic atrophy causes them to look more like pits.
"Arteriolar nephrosclerosis" is a sandpaper-surfaced kidney due
to
nephrons dropping out randomly from arteriolar disease. |
Is this a kidney with most or all of the following: ...hemorrhages throughout its substance; ...fibrinoid necrosis/thrombosis of the small arteries, arterioles, and glomeruli; ...striking myxoid and/or onion-skin proliferation of the intima of small arteries?
Does the patient also have spectacular high blood pressure and
other
resulting problems? |
Malignant hypertension |
Are glomerular capillaries distended by hyaline pink masses? |
Fibrin-platelet thrombi
Consider DIC, TTP, hemolytic-uremic syndrome, eclampsia. |
Is it a glomerulus with its capillary loops thickened by a
subendothelial layer of finely-granular material composed of
fibrin and
platelet debris? Do you perhaps also see fragments of red cells
here?
Do you perhaps also see impressive onion-skin changes of the
intimal
layers of the small arteries? |
Hemolytic-uremic syndrome |
Is it a kidney with its cortex more or less diffusely yellow, and
this
is sudden, total renal failure rather than nephrotic syndrome?
And do
you perhaps know the patient had shock and/or DIC? |
Diffuse renal cortical necrosis |
Is it a depressed, white, V-shaped scar of the kidney? |
Old renal infarct |
Are the renal pelvis and calyces massively inflated due to
obstruction
distally? |
Hydronephrosis
Beginners: Tell this from adult polycystic kidney because the
dilated
portions of kidney all communicate with one another! |
Is it a yellow nodule in the renal cortex, and is it less than 3
cm and
free of histologic evidence of malignancy? |
Renal cortical adenoma
NOTE: This lesion really exists, but it's impossible to tell from
a
tiny low-grade cancer without DNA study. |
Is it a yellow (usually) mass in the kidney of an adult, with
hemorrhage (usually) and necrosis (usually)?
Is it a renal mass composed of clear (usually) polygonal (less
often,
spindle) cells with distinct intercellular boundaries, and do you
see
any of: |
Renal cell carcinoma / "hypernephroma" / Grawitz tumor / "kidney
cancer" / adenocarcinoma of the kidney |
Is it a grossly malignant primary tumor in the kidney of a
child?
Does it contain some or all of the following:
Did the guy in the DNA lab say that the WT locus is deleted? |
Wilms' tumor / nephroblastoma |
Is it a white and yellow, grossly benign nodule from the renal
cortex? Is it a renal mass composed of a mix of fat, smooth muscle, and blood vessels?
Does the patient perhaps have tuberous sclerosis? |
Angiomyolipoma |
Is it a round, sharply-circumscribed, tan tumor in the kidney,
exhibiting a central white, star-shaped scar?
Is it a histologically benign kidney tumor with cells packed with
mitochondria ("oncocytes"; "Hšrthle cells")? |
Hšrthle cell adenoma / oncocytoma
NOTE: These may occasionally metastasize. |
Is it a papillary tumor apparently arising from the epithelium of
the
renal pelvis? |
Urothelial (transitional cell) carcinoma of the kidney |
Are there chunks of transitional epithelial cells apparently
lying in
the lamina propria below the normal transitional epithelium? |
Brunn's nests |
Are there tiny cysts lying in the lamina propria below the normal
transitional epithelium? |
Cystitis cystica / ureteritis cystica |
Is the urothelium dotted with abundant lymphoid follicles? |
Cystitis follicularis / ureteritis follicularis |
Is it a ureter that is substantially dilated for any reason? |
Hydroureter |
Is it a bladder with an out-pouching of the entire wall, or
mostly
mucosa with perhaps some muscularis visible? |
Bladder diverticulum |
Does the bladder mucosa communicate with the skin over the pubis
because of a birth defect? Is there perhaps associated bladder
infection, squamous metaplasia, and/or adenocarcinoma of the
bladder? |
Exstrophy of the bladder |
Is it a voiding urogram showing contrast medium from the bladder
refluxing into the ureter or even the renal pelvis? |
Vesicoureteral reflux |
Is it a communication between the bladder mucosa and the
umbilicus? |
Persistent urachus |
Is it one or more cysts lying between the bladder and the
umbilicus? |
Urachal cysts |
Is the bladder acutely and/or chronically inflamed? |
Cystitis |
Are all layers of the bladder wall chronically inflamed and
scarred? |
Ulcerative interstitial cystitis / Hunner's ulcer |
Is it a urinary bladder with several slightly-raised yellow
plaques on
its mucosa? Is it a lesion from the urinary bladder (or perhaps elsewhere) composed of macrophages containing abundant lipid and round, calcified "Michaelis-Gutmann" bodies? |
Malakoplakia |
Is it flat (i.e., not a papillary tumor) transitional epithelium
with
more than 7 apparent layers of nuclei (the exact number varies
depending on your authority)? |
Transitional cell hyperplasia |
Is it a papillary growth on the urothelium with transitional
epithelium with 7 or fewer apparent layers of nuclei? |
Transitional cell papilloma |
Is it a papillary growth on the urothelium, with more than 7
apparent
layers of nuclei?
Is it an invasive carcinoma apparently arising from urothelium,
with or
without a papillary component, without obvious glandular or
squamous
features in most areas? |
Transitional cell carcinoma / bladder cancer |
Is it flat transitional epithelium with obvious cellular
atypia? |
Transitional cell atypical hyperplasia / carcinoma in situ |
Is it a squamous cell carcinoma of the bladder, and there is a
curious
foreign body which might be a Schistosoma haematobium
egg? |
Squamous cell carcinoma of the bladder in schistosomiasis |
Is it a man with an acutely inflamed urethra, with pain and at
least
some discharge? |
Urethritis
In addition to gonorrhea and chlamydia, remember trichomonas
(after
intercourse), meningococcus (after oral sex), and eating lots of
those
little jalape¤o peppers |
Is it an uncomfortable, small red mass at the external urethral
meatus
of a woman? If someone was foolish enough to biopsy it, do you
see
apparent granulation tissue? |
Urethral caruncle |
Is it a hexagonal crystal in the urine? |
Cystine or uric acid
NOTE: Cystinuria is serious and treatable. Uric acid crystals
are
normal in acid urine. |
Is it an octahedral crystal in the urine? |
Calcium oxalate
NOTE: Normal to have a few. |
Is it a coffin-lid crystal in the urine? |
Magnesium ammonium phosphate (struvite)
NOTE: Proteus infection. |
Is it plate-like crystals in the urine? |
Cholesterol crystals |
Is it needle-shaped crystals in the urine, gathered as
sheaves? |
Tyrosine or contrast medium |
Is this a bicycle-wheel crystal in the urine? |
Leucine |
Is this a male with the urethra opening on the dorsal surface of
the
penis? |
Epispadias |
Is this a male with a foreskin which cannot be retracted
backwards over
his corona? |
Phimosis |
Is this an uncircumcised male with phimosis or extremely poor
personal
hygiene, who now is infected and sore? |
Balanoposthitis |
Is this a male with a tight foreskin which he did manage to
retract
backwards over his corona, and now cannot put it back over his
glans? |
Paraphimosis |
Is this one or more large, benign warts on the genitals of a man
or a
woman?
Is this skin from the genitals, and do you see some or all of the
following:
Is this a lesion from the genitals, and somebody showcases human
papillomavirus (HPV) using a DNA probe? |
Condyloma acuminatum
NOTE: Very large, locally invasive ones are verrucous carcinoma /
giant condyloma of Buschk‚-Lowenstein; these shouldn't
metastasize
however. |
Is it one patch of red skin on the external genitals of an older
man
(scrotum, shaft) or older woman, (or perhaps skin someplace
else), with
marked cytologic atypia of the epidermis but no invasion? |
Bowen's disease |
Is it several patches of brown, warty lesions on the genitals of
a
younger man or younger woman, with marked cytologic atypia of the
epidermis but no invasion? Has HPV type 16 perhaps been
showcased in
the lesion? |
Bowenoid papulosis |
Is it a red patch on a man's glans, with marked cytologic atypia
of the
epidermis but no invasion? |
Erythroplasia of Queyrat |
Is it a fungating squamous cell carcinoma arising around the
coronal
sulcus? Is the patient (probably) an uncircumcised, un-hygienic
man?
Has HPV perhaps been showcased in the lesion? |
Cancer of the penis |
Is at least one testis undescended? |
Cryptorchidism |
Is it an adult man's testis, but there is no sperm production in
any of
the tubules? |
Testicular atrophy
Consider cryptorchidism, XXY Klinefelter's, pituitary
insufficiency,
old torsion, old mumps, taking estrogen, radiation injury,
chemotherapy, old age, liver failure, kwashiorkor-marasmus, mild
cystic
fibrosis, obstruction from vasectomy or other |
Is it a mass in the testis composed primarily of granulomas both
within and between the tubules, with some plasma cells and no
obvious
cause? |
Granulomatous orchitis |
Has the cremaster muscle gone into spasm, twisting the spermatic
cord
540ø, occluding the pampiniform plexus, and causing venous
infarction
of the testis? |
Torsion of the testis |
Is it a soft, yellow testicular tumor? And on microscopy, do you
see
cells with abundant cytoplasm and round, centrally-located
nuclei, and
very sharply-defined cell borders, arranged in nests ("organoid
pattern"), separated by thin fibrous bands rich in lymphocytes?
Do you
perhaps see granulomas? Do you perhaps see syncytiotrophoblast
(but
never cytotrophoblast)? |
Classic seminoma |
Is it a soft, gray testicular tumor? And on microscopy, do you
see
tumor cells resembling spermatocytes, with great variability in
tumor
cell size, and no lymphocytes? |
Spermatocytic seminoma
NOTE: Almost benign. |
Is it a variegated gray, typically hemorrhagic and necrotic
testicular
tumor composed of sheets, cords, rings and/or papillae of very
primitive cells with poorly-defined borders and abundant purple
cytoplasm? |
Embryonal cell carcinoma |
Is it a multinucleated cell, in any testicular tumor, that stains
positive for hCG? |
Syncytiotrophoblast |
Is it a cell in any testicular tumor that stains positive for à-
fetoprotein (AFP)? |
Yolk sack cell |
Is it a pale yellow, gelatinous testicular tumor, perhaps from a
boy,
with rings-within-rings ("Schiller-Duvall bodies") recalling
embryonic
vitelline duct, and hyaline globules staining positive for à-
fetoprotein (AFP) and à1-protease inhibitor? |
Yolk sack tumor ("endodermal sinus tumor") |
Is it a soft, mushy, bloody-red tumor of the testis that contains
both
syncytiotrophoblast and cytotrophoblast? Is hemorrhage obvious
grossly
and microscopically? |
Choriocarcinoma |
Is it a testicular tumor composed microscopically of a mix of
identifiable benign tissues, without cancer or primitive
material? |
Mature teratoma |
Is it a testicular tumor composed microscopically of a mix of
identifiable benign tissues and some very primitive tissues such
as are
seen in an embryo? |
Immature teratoma |
Is it a testicular tumor composed microscopically of a mix of
identifiable benign tissues plus an obvious cancer (typically
squamous
cell carcinoma or carcinoid)? |
Teratoma with malignant transformation |
Is it a round, golden-brown testicular nodule composed of pink,
polygonal cells, with perhaps a Reinke crystalloid? |
Leydig cell tumor ("interstitial cell tumor") |
Is it a pale testicular tumor composed of cords of cells that
tend to
take a wedge-shape? |
Sertoli cell tumor ("androblastoma") |
Is it a round, white nodule in the epididymis? Microscopically,
is it
a mix of fibrous tissue and epithelial cells without other
distinguishing features? |
Adenomatoid tumor |
Is it excess fluid in the tunica vaginalis? |
Hydrocele |
Is it a bunch of little rough red bumps on an older man's
scrotum?
Is it lots and lots of little rough red bumps on the penis and
scrotum
of a patient with Fabry's disease? |
Angiokeratomas |
Is it an older man's prostate with large soft-to-firm nodules
around
the urethra, compressing the surrounding tissue? Is it an older man's prostate with nodules forming a "median bar" protruding upward into the bladder outlet? Is it an older man's prostate that is very large?
Is it prostate nodules composed of collagen and/or muscle and/or
two-
cell-layer-thick glands with exaggerated papillary
infoldings? |
Prostatic hyperplasia ("benign prostatic hypertrophy") |
Is it a dominant hard mass in an older man's prostate? Is it an apparent cancer arising in an older man's prostate, typically in the posterior lobe, and invading the surrounding tissue?
Is it glands in the prostate that are crowded, or that seem to
invade
among benign glands distorting the normal architecture, or that
have
prominent nucleoli, or that have nuclei with marginated
chromatin, or
that have lost their myoepithelial cell layer? |
Prostate cancer (prostatic adenocarcinoma) |
Is it a vulvitis or vaginitis with white patches that scrape off?
Do
you see pseudohyphae in the scrapings under the microscope? |
Candida |
Is it a vaginitis with considerable redness ("strawberry"), with
superficial inflammation? Do you see trichomonads in the
discharge? |
Trichomonas |
Is it glands in the vaginal wall, with plentiful cytoplasm? And
is
there probably a history of exposure to exogenous estrogen (i.e.,
diethylstilbestrol) in utero? |
Vaginal adenosis |
Is it a clear-cell adenocarcinoma involving the vagina? And is
there
probably a history of exposure to exogenous estrogens (i.e.,
diethylstilbestrol) in utero? |
Vaginal adenocarcinoma |
Are the oviducts distended and inflamed? Is there pus
formation? Are the folds of the oviduct edematous and rich in neutrophils? Are the oviducts extensively scarred?
Are the oviducts distended by non-inflammatory fluid held there
by
scarring? |
Pelvic inflammatory disease
NOTE: Consider gonorrhea, chlamydia, others. |
Is it a cyst at the vaginal introitus? |
Bartholin's gland cyst |
Is it a dense, shiny area on the vulvar or penile skin?
Is it a portion of vulvar or penile skin with epidermal thinning,
very
dense dermal collagen, and an edematous zone under the
epidermis? |
Lichen sclerosus |
Is it vulvar or perineal skin with the epidermis invaded by
individual
bizarre cells? Are the cells mucin and/or CEA positive? |
Extramammary Paget's disease |
Is it vulvar or perineal skin with the epidermis invaded by
individual
bizarre cells? Are the cells mucin negative and CEA negative,
but
exhibit melanin or S100 positivity? |
Malignant melanoma |
Is it a bosselated, soft mass in the bladder or vagina? Under
the
microscope, do you see a dense "cambium layer" under the
epithelium,
and a looser fibromyxoid stroma deeper? And, do you perhaps see
a
plausible rhabdomyoblast? |
Sarcoma botryoides |
Is it a vaginal smear and you see squamous cells with abundant
adherent bacteria ("clue cells")? |
Gardnerella |
Is it a fibromyxoid structure hanging from the cervical os by a
peduncle? |
Endocervical polyp |
Is it a striking hyperplasia of the columnar cells of the
endocervix,
in a woman receiving extra progesterone or with a progesterone-
producing tumor? |
Microglandular endocervical hyperplasia |
Is it a cervix that appears normal, but fails to stain with
iodine
("Schiller test")? Does the skilled culposcopist perhaps believe
a
lesion is present? Does pap smear or biopsy confirm replacement
of the
epithelium by abnormal cells without invasion of the stroma? |
Carcinoma in situ of the cervix |
Is it an invasive squamous cell carcinoma (most common) or
adenocarcinoma of the cervix? |
Cancer of the cervix
|
Is it an endometrial biopsy containing at least a few plasma
cells? |
Chronic endometritis
NOTE: If there are no retained fragments of a pregnancy, and the
patient does not have an IUD in place, and the patient does not
have
gonorrhea, consider blaming chlamydia. |
Is it an endometrium or oviduct containing granulomas and perhaps
giant cells? Does acid-fast stain perhaps show mycobacteria? |
Tuberculosis of the endometrium / oviduct |
Do you see at least two of the following, in the same place,
outside
the endometrial cavity: ...endometrial glands; ...endometrial stroma; ...evidence of old hemorrhage, i.e., hemosiderin-laden macrophages?
Is it a chocolate cyst of the ovary? |
Endometriosis
NOTE: If it's in the myometrium, call it adenomyosis. |
Is it endometrium from the latter portion of the cycle, with
continued
mitotic activity and large glands, and without secretory
changes? |
Anovulatory cycle |
Is it endometrium from the latter portion of the cycle, with
minimal or
no secretory changes? |
Inadequate luteal phase |
Is it a soft, nodular mass in the endometrial cavity, composed of
normal or anovulatory-cycle type endometrium? |
Endometrial polyp |
Are the endometrial glands markedly variable in size, with some
cysts,
with perhaps piling-up of the cells, but no increase in number
and no
cytologic atypia? |
Simple endometrial hyperplasia |
Are the endometrial glands markedly variable in size and shape,
and
also increased in number, but with no cytologic atypia? |
Complex endometrial hyperplasia ("adenomatous hyperplasia of
endometrium without atypia") |
Are the endometrial glands markedly variable in size and shape,
and
crowded, and probably branching, and there is some anaplasia, but
the
fundamental architecture of discrete glands in a stroma is
preserved? |
Atypical endometrial hyperplasia ("adenomatous hyperplasia of
endometrium with atypia") |
Is it endometrium with poorly-developed glands but with a lush,
mitotically active, perhaps decidualized stroma? |
Oral contraceptive pill effect |
Is it a thin endometrium, mostly gone except for the basalis?
Are some
of the glands perhaps cystically dilated? |
Post-menopausal endometrium |
Is it an epithelial malignancy of the endometrium, growing as
glands
and/or sheets? |
Adenocarcinoma of the endometrium ("cancer of the uterus") |
Is it an adenocarcinoma of the endometrium with benign squamous
metaplasia? |
Adenoacanthoma of the endometrium |
Is it an adenocarcinoma of the endometrium with malignant
squamous
elements? |
Adenosquamous carcinoma of the endometrium |
Is it a round, white mass within, hanging off of, or immediately
subjacent to the myometrium? Is it a benign spindle cell tumor of the myometrium?
Has it perhaps undergone central infarction, fibrosis,
calcification,
and/or "cystic" change? |
Leiomyoma ("fibroid") |
Is it a spindle cell tumor of the myometrium with mitotic
figures? |
Leiomyosarcoma or endometrial stromal sarcoma
NOTE: Ask your instructor whether you need to learn to
distinguish
these. |
Is it a spindle cell tumor with scanty cytoplasm, infiltrating
between
myometrial muscle bundles and invading lymphatics? |
Low-grade endometrial stromal sarcoma ("endolymphatic stromal
myosis") |
Is it a cancer of the uterus with both adenocarcinoma and
malignant
mesenchymal elements? |
Malignant mixed mesodermal tumor ("mixed Mšllerian tumor")
TERMS: "Heterologous" examples contain differentiated mesenchyme
(muscle, cartilage, etc.) "Homologous" ones are simply
primitive. |
Is it a mucus-filled cyst adjacent to an oviduct? |
Hydatid of Morgagni / parovarian cyst |
Is it a benign ovarian cyst lined by flattened cells? |
Follicular ovarian cyst |
Is it a benign ovarian cyst lined by luteinized, yellow
cells? |
Luteal ovarian cyst |
Is it a pair of enlarged ovaries with thick outer fibrous layer
and
innumerable cysts?
Is this a young woman with excess gonadotropins, androgens, and
estrogens, as well as amenorrhea? Is she perhaps also hirsute
and/or
obese? |
Stein-Leventhal polycystic ovaries |
Is it an ovarian cystic tumor lined by a single layer of benign,
ciliated cells like in the oviduct? |
Serous cystadenoma of ovary |
Is it an ovarian tumor with cells as in a serous cystadenoma, but
with
a much more abundant stroma and less tendency to form large cysts
or
papillae? |
Cystadenofibroma of ovary |
Is it an ovarian cystic tumor lined by atypical ciliated cells,
perhaps with some piling up, but without stromal invasion? |
Borderline serous cystadenocarcinoma of ovary |
Is it an ovarian tumor composed of tall, columnar, non-mucin-
secreting malignant cells, perhaps with a cystic and/or papillary
growth pattern and/or psammoma bodies, perhaps with cilia, and
with
stromal invasion? Are both ovaries perhaps involved? |
Serous cystadenocarcinoma of ovary |
Is it an ovarian cystic tumor, perhaps multi-loculated and/or
very
large, lined by a single layer of columnar cells like in the
endocervix? |
Mucinous cystadenoma of ovary |
Is it an ovarian cystic tumor lined by atypical mucin-producing
cells,
perhaps with some piling up, but without stromal invasion? |
Borderline mucinous cystadenocarcinoma of ovary |
Is it an ovarian tumor composed of mucin-producing malignant
cells,
perhaps with a cystic growth pattern, and with stromal
invasion? |
Mucinous cystadenocarcinoma of ovary |
Is it an ovarian tumor with back-to-back glands and perhaps
squamous
areas, as in a familiar-type endometrial adenocarcinoma? |
Endometrioid carcinoma of ovary
|
Is it an ovarian tumor composed of malignant glands with cells
exhibiting abundant, clear cytoplasm? |
Clear-cell adenocarcinoma of ovary |
Is it a solid ovarian tumor with an ovarian spindle-cell type
stroma
containing islands of transitional cell epithelium? |
Brenner tumor |
Is it an ovarian tumor with an inner lining surface of skin and a
central cyst containing sebum, keratin, and hair? Are all the
tissues
in "Rokitansky's nodule" in the wall benign, resembling an
adult's? Is
there perhaps a tooth? |
Mature cystic teratoma of ovary ("dermoid cyst") |
Is it a solid ovarian tumor containing a variety of tissues,
including
some primitive elements typical of an embryo? |
Immature teratoma of ovary |
Is it an ovarian tumor with the typical appearance of a
carcinoid? Is
carcinoid syndrome perhaps present? Is urinary 5-HIAA perhaps
elevated? |
Ovarian carcinoid ("specialized teratoma") |
Is it an ovarian tumor composed primarily of thyroid tissue? |
Struma ovarii ("specialized teratoma") |
Is it a soft, yellow ovarian tumor? And on microscopy, do you
see
cells with abundant cytoplasm and round, centrally-located
nuclei, and
very sharply-defined cell borders, arranged in nests ("organoid
pattern"), separated by thin fibrous bands rich in lymphocytes?
Do you
perhaps see granulomas? Do you perhaps see syncytiotrophoblast
(but
never cytotrophoblast)? |
Dysgerminoma |
Is it a pale yellow, gelatinous ovarian tumor, perhaps from a
boy, with
rings-within-rings ("Schiller-Duvall bodies") recalling embryonic
vitelline duct, and hyaline globules staining positive for à-
fetoprotein (AFP) and à1-protease inhibitor? |
Yolk sack tumor ("endodermal sinus tumor") |
Is it a soft, mushy, bloody-red tumor of the ovary that contains
both
syncytiotrophoblast and cytotrophoblast? Is hemorrhage obvious
grossly
and microscopically? |
Choriocarcinoma |
Is it a solid, white ovarian tumor composed of
non-lipid-containing
spindle-shaped cells? |
Ovarian fibroma |
Is it a solid, yellow ovarian tumor composed of luteinized,
lipid-
containing spindle-shaped theca cells? Has it perhaps produced
some
hormone, probably estrogen? |
Thecoma
NOTE: If small, consider also stromal luteoma. |
Is it a solid, yellow, solid or cystic ovarian tumor composed of
epithelial-type cells, perhaps making miniature fluid-filled
follicles
("Call-Exner bodies")? Do you perhaps see grooved, coffee-bean
nuclei?
Has it perhaps produced some hormone, probably estrogen? |
Granulosa cell tumor |
Is it a pale ovarian tumor composed of cords of cells that tend
to take
a wedge-shape, plus polygonal, pink-staining cells with perhaps a
Reinke crystalloid? Has it perhaps produced some hormone,
probably
androgen? |
Sertoli-Leydig cell tumor ("androblastoma";
"arrhenoblastoma") |
Is it a pale ovarian tumor composed of entirely of polygonal
pink-
staining cells with perhaps a Reinke crystalloid? Has it perhaps
produced some hormone, probably androgen? |
Pure Leydig cell tumor ("Hilus cell tumor") |
Is it a yellow ovarian tumor composed of entirely of lipid-rich
cells?
Has it perhaps produced androgen? |
Lipid cell tumor |
Is it a yellow ovarian mass composed of cuboidal cells, later in
pregnancy, perhaps with virilization? |
Pregnancy luteoma |
Is it an ovarian tumor composed of embryoid bodies? |
Polyembryoma |
Is it an ovarian or testicular tumor composed of a mix of germ
cell and
sex-cord stroma structures, probably including granulosa and
Sertoli
cells, perhaps with dysgerminoma, Leydig cells, and/or theca
cells?
Does the patient perhaps have one of the intersex conditions, or
undescended testes? |
Gonadoblastoma |
Is it an ovarian tumor with a mix of granulosa-theca and Sertoli-
Leydig elements? |
Gynandroblastoma |
Is it an ovarian tumor with a mix of serous, mucinous,
endometrioid-
clear cell, and/or Brenner tumor? |
Mixed coelomic ovarian tumor |
Is it a portion of umbilical cord with abundant neutrophils? |
Funisitis |
Is it a portion of fetal membranes with abundant neutrophils? |
Chorioamnionitis |
Is it a hematoma separating the placenta from the uterine wall
prior to
the birth of the child? |
Abruption of the placenta |
Is it a placenta overlying the inner cervical os? |
Placenta previa |
Is it a placenta which has stuck to the uterine wall and not
delivered
after birth, because the decidua did not form properly? |
Placenta accreta |
Is it normal-appearing trophoblastic villi and/or fetal parts
outside
the uterine cavity?
Is it an oviduct distended with blood? |
Ectopic pregnancy
|
Is she several months pregnant, and do you see some or all of the
following: ...intrahepatic hemorrhages; ...periportal hepatic necrosis with fibrin deposition; ...swollen endothelial cells in the glomeruli; ...fibrin deposition under the endothelial cells in the glomeruli; ...fibrinoid necrosis of uterine arteries; ...lipid deposition ("acute atherosis") in the intima of the uterine arteries ...fibrin microthrombi in the brain? |
Eclampsia |
Is it uterine contents that resemble at least dozens of small
grapes?
Is it swollen trophoblastic villi with at least minimal
proliferation
of the trophoblast, and poor or no development of the vessels in
the
villi? |
Hydatidiform mole |
Is it a hydatidiform mole with no fetal parts anywhere, and
almost all
villi are involved?
Is it a hydatidiform mole and somebody who understands these
things
says the karyotype is a normal child's but chromosomes are all of
paternal origin? |
Complete ("classic") hydatidiform mole |
Is it a hydatidiform mole with many uninvolved villi and/or at
least
some fetal parts?
Is it a hydatidiform mole and the karyotype is triploid or
tetraploid? |
Partial hydatidiform mole |
Is it both syncytiotrophoblast and cytotrophoblast invading the
wall of
the uterus and/or metastatic from a pregnancy or hydatidiform
mole? |
Invasive mole ("chorioadenoma destruens") or choriocarcinoma |
Is it a small accessory nipple or breast somewhere on the line
from the
axilla to the groin on either side? |
Supernumerary nipple / supernumerary breast |
Is it a portion of breast tissue that has become inflamed during
nursing, perhaps with abscess formation? Has Staph.
aureus
perhaps been demonstrated on smear or culture? |
Acute mastitis / breast abscess |
Is it a lump in the breast, perhaps at a site of a blow, in which
lakes of free lipid are surrounded by scar, lipid-laden
macrophages,
neutrophils, calcification, and/or granuloma formation? |
Fat necrosis of breast |
Is it a dilated duct in a lactating breast, filled with milk? |
Galactocele |
Is it a lump in the breast composed of a group of dilated ducts
fill of
inspissated secretion, and surrounded by granulomas and perhaps
also
plasma cells? |
Mammary duct ectasia / plasma cell mastitis |
Is it breast tissue with a shotty consistency? Is most of the
tissue
in both breasts perhaps of similar consistency? Are the breasts
perhaps extra tender before menstruation? Is it an unopened cyst of the breast that appears blue?
Is it a portion of breast with more dense stroma than usual, and
scattered cyst formation? |
Cyst formation and fibrosis of breast ("fibrocystic disease") |
Is it cells proliferating in the ducts and/or lobules of the
breast,
perhaps extending into the lumen, perhaps with irregular lumen
formation within the mass, but without obvious cribriform
pattern, hyperchromatic nuclei, or cell uniformity (sic). |
Epithelial hyperplasia of breast
Variants: Ductal papillomatosis of breast (good papillae),
atypical
hyperplasia of breast (cytology and/or arrangement looks
malignant) |
Is it breast tissue with little ducts and glands surrounded by
fibrosis, looking perhaps like cancer but always maintaining the
normal lobular architecture? |
Sclerosing adenosis |
Is it a small lesion in a duct near the nipple that appears to be
a
papilloma? Has the patient perhaps experienced nipple bleeding?
Are
at least some of the following present: ...fibrous stalk; ...good myoepithelial cell layer; ...apocrine metaplasia; ...hyalinization; ...no features of carcinoma in situ? |
Papilloma of breast |
Is it a papillary lesion in a duct near the nipple? Are at least
some
of the following present: ...cellular atypia; ...cellular uniformity; ...cribriform pattern; ...mitotic figures? And are these absent: ...fibrous stalk; ...good myoepithelial cell layer; ...apocrine metaplasia; ...hyalinization? |
Papillary carcinoma of breast |
Is it a sharply-circumscribed, round tumor in the breast, with
more-or-
less compressed ducts in a more-or-less loose fibrous stroma? |
Fibroadenoma |
Is it a circumscribed, round, mixed epithelial-and-stromal tumor
of the
breast divided into lobules by slits "like the veins in a
leaf"? |
Phyllodes tumor |
Is it a phyllodes tumor of breast with mitotic figures, cellular
atypia, and/or cellular crowding in the stroma? |
Malignant phyllodes tumor |
Is it a section of breast containing intraductal carcinoma with
necrotic cancers in the centers of the lumens? |
Intraductal breast carcinoma, comedocarcinoma pattern |
Is it cribriform growth of relatively uniform cells in ducts of
breast? |
Intraductal breast carcinoma, cribriform pattern |
Is it breast with its terminal ducts distended by large cells,
pretty
much uniform, with small nucleoli? |
Lobular carcinoma in situ of breast |
Is it a hard lump in the breast, with perhaps a gritty texture, a
tendency to retract below the cut surface (elastic effect) and a
mixed
yellow and white pattern?
Is it breast with more-or-less malignant looking cells invading a
desmoplastic stroma as cords ("Indian files"), sheets, tubes, or
some
other adenocarcinoma-type pattern? |
Scirrhous carcinoma of breast |
Is it a large, soft breast cancer composed of large, malignant
cells in
sheets, with abundant lymphocytes between the sheets? |
Medullary carcinoma of breast |
Is it extremely well-differentiated, one-layered tubes of cells,
infiltrating the breast stroma? |
Tubular carcinoma of breast |
Is it a gelatinous breast cancer with abundant extracellular
mucin, in
which float cancer cells? |
Mucinous carcinoma of breast |
Is it small cancer cells with scanty cytoplasm and rather small
nuclei, forming single files ("Indian files") as they infiltrate
stroma? |
Lobular carcinoma of breast |
Is it nipple with the epidermis invaded by individual bizarre
cells?
Are the cells mucin and/or CEA positive? |
Paget's disease of the nipple |
Is it a portion of male breast with hyperplasia of the ducts,
perhaps
also with extra connective tissue around the ducts? |
Gynecomastia |
Is it a round, expansile lesion in the sella turcica? Is it a clearly-circumscribed nodule of uniform cells within the adenohypophysis?
Is it an electron micrograph of a pituitary lesion showing
uniform
cells with pituitary-type secretory granules? |
Pituitary adenoma
NOTE: Almost all benign. Metastasis is the only proof of
malignancy.
Consider checking for Wermer's MEN-I. |
Is he or she a extra-tall youngster with a pituitary adenoma
(probably
"acidophilic")? |
Pituitary gigantism |
Is he or she a person who never grew, and who fails the hGH
stimulation test? |
Pituitary dwarfism
NOTE: Similar dwarfism, but with high hGH occur in people who
lack hGH
receptors and/or somatomedin. |
Is he or she a person with several of the following: ...tall stature; ...frontal bossing; ...spade fingers; ...thick lips and big tongue; ...deep voice; ...good musculature; ...glucose intolerance; ...myopathy / neuropathy? |
Acromegaly
NOTE: The usual cause is a pituitary adenoma, probably
"acidophilic". |
Is he or she a person with several of the following: ...round, red face; ...extra fat on the back of the neck ("buffalo hump"); ...increased appetite and weight gain; ...atrophy of the muscles; ...thinning of the skin, perhaps with purple striae; ...fragile capillaries; ...acne; ...ringworm; ...hypertension; ...glucose intolerance; ...depression; ...psychosis? |
Cushing's syndrome |
Is it a person with Cushing's syndrome and a pituitary adenoma
(probably a basophilic microadenoma) causing adrenal gland
hyperplasia? |
Cushing's disease |
Is she a woman during reproductive life, not a new mother, who
has
stopped having her periods and is lactating? |
Galactorrhea-amenorrhea syndrome
NOTE: This patient has a prolactinoma until proven otherwise. |
Is this a pituitary adenoma of any H&E appearance that stain
positive
for prolactin?
Is he a man who has lost his libido despite perhaps normal
testosterone levels, and has elevated blood prolactin and/or a
pituitary mass? |
Prolactinoma |
Is this an adult with an anterior pituitary lesion and at least
some of
the following: ...weight loss; ...mental changes; ...loss of sexual hair; ...amenorrhea / loss of libido; ...hypothyroidism; ...nausea? |
Hypopituitarism ("Simmonds's disease") |
Is it an anterior pituitary that has undergone infarction during
an
episode of shock around the time of parturition? |
Sheehan's syndrome
NOTE: Some usage allows "Sheehan's syndrome" to cover massive
pituitary infarction from any cause. |
Is it an anterior pituitary gland that has undergone pressure
atrophy
from the arachnoid herniating through the diaphragma sellae? |
Empty-sella syndrome |
Is it an adenohypophysis from a patient with Cushingism from any
cause, and the basophilic cells are packed with intermediate
filaments
imparting a hyaline appearance? |
Crooke's hyaline change
NOTE: A classic bit of the real arcana of pathologic anatomy. |
Is it a tumor in the hypothalamic-pituitary region, with at least
several of the following: ...cysts containing "machine oil" cholesterol-rich debris; ...myxoid stroma surrounded by columnar cells with basal vacuoles as in ameloblasts ...squamous elements (pearls, desmosomes, keratin) without malignancy; ...calcification? |
Craniopharyngioma |
Is he or she a patient with several of the following: ...recent weight loss; ...fine tremor (try putting a paper over the outstretched hands) ...anxiety, "nervousness"; ...hyperdynamic heart; ...atrial fibrillation; ...diarrhea; ...lid lag; ...feels warm and moist? |
Hyperthyroidism |
Is he or she a person with most or all of the following: ...mental and physical sluggishness; ...increased mucopolysaccharide ground substance in connective tissue ("myxedema"); ...hoarseness; ...constipation; ...cold skin; ...dry, brittle hair; ...cardiomyopathy; ...delayed "hung" brief tendon reflexes; ...high serum cholesterol; ..."depression" and/or "psychosis"? |
Hypothyroidism |
Is or was he or she a child with mental retardation, delayed
development, and other familiar signs of hypothyroidism? |
Cretinism |
Is it a midline neck mass lined by thyroid and/or squamous
epithelium? |
Thyroglossal duct cyst |
Is it a miniature, white thyroid gland with histology showing
mostly
fibrosis, with only a few remaining thyroid epithelial cells? |
End-stage thyroid ("thyroid atrophy")
Consider burned-out Hashimoto's, burned-out DeQuervain's,
hypopituitarism, radiation effect. |
Is it a thyroid gland containing abundant lymphocytes, but no
germinal
centers or Hšrthle cells, perhaps in a hypothyroid patient? |
Lymphocytic thyroiditis |
Is it a thyroid gland containing abundant lymphocytes and
probably
plasma cells, with germinal center formation and Hšrthle cell
formation? |
Hashimoto's thyroiditis |
Is it a thyroid gland with loss of follicular epithelial cells
and
active granuloma formation, apparently a foreign-body reaction to
liberated colloid? |
DeQuervain's subacute granulomatous thyroiditis
NOTE: If painless, some call it "subacute lymphocytic
thyroiditis" |
Is it a proliferation of fibroblasts and collagen beginning in
the
thyroid gland and perhaps adhering to nearby neck structures? |
Riedel's thyroiditis |
Is he or she a patient with two or more of these: ...hyperthyroidism, usually with autoantibodies against the hTSH receptor; ...exophthalmos due to increased tissue behind the eyeball; ...pretibial myxedema? |
Graves' disease |
Is this thyroid gland from someone known to be taking medication
for
hyperthyroidism, and the follicular epithelium is thrown up into
elaborate papillae and/or otherwise hyperplastic? |
Propylthiouracil effect in thyroid |
Is this thyroid gland from someone known to be taking medication
for
hyperthyroidism, and the follicular epithelium is flat and
inactive and
there is abundant colloid? |
Iodine excess effect in thyroid |
Is this a portion of a diffusely enlarged thyroid gland, and you
see
"scalloping" resorption vacuoles in the colloid adjacent to the
epithelial cells (i.e., the colloid is being rapidly
metabolized)?
Is this a section of a diffusely enlarged thyroid gland with the
colloid almost gone, with tall epithelial cells? |
Diffuse thyroid hyperplasia |
Is the thyroid gland diffusely enlarged and perhaps hypercellular
in
simple iodine deficiency and/or the absence of demonstrable
thyroid
disease? |
Simple diffuse nontoxic goiter
NOTE: Growing goiters tend to be hypercellular. When sufficient
cell
mass is achieved, colloid accumulation becomes possible,
producing the
"colloid goiter". |
Is it an enlarged thyroid with many nodules, and perhaps some of
the
following: ...colloid-rich nodules; ...colloid-poor nodules; ...irregular scarring; ...irregular calcification; ...irregular hemosiderin deposits. |
Multinodular goiter / adenomatous goiter |
Is it a single nodule in a thyroid gland, composed of benign
cells
without papilla formation? |
Thyroid adenoma
NOTE: The subtypes aren't of much consequence. |
Is it a section of thyroid immunostained to demonstrate the
calcitonin-producing C-cells, and they are much more numerous
than in
your "Histology" book? |
C-cell hyperplasia
NOTE: Precursor lesion to medullary carcinoma. The patient
almost
certainly has Sipple's MEN-II. |
Is it a thyroid tumor with any one of the following: ...gross appears as a tiny white stellate scar; ...optically clear "Orphan Annie eye" nuclei; ...widespread papilla formation; ...psammoma bodies? |
Papillary adenocarcinoma of the thyroid |
Is it an apparently circumscribed thyroid nodule, but histology
shows
follicles or sheets of cells invading vessels?
Is it a grossly malignant-appearing tumor in the thyroid,
calcitonin-
negative and perhaps thyroglobulin-positive, composed of
reasonably
well-differentiated epithelial cells but without features of a
papillary carcinoma? |
Follicular adenocarcinoma of the thyroid |
Is it a fairly well-differentiated thyroid carcinoma which does
any of
the following: ...produces calcitonin, detected by immunoperoxidase and/or serum assay; ...produces ACTH (Cushingism), VIP (diarrhea), and/or serotonin (carcinoid syndrome); ...has an amyloid stroma composed (if you can check it) of á- pleated calcitonin; ...shows neurosecretory-type granules on electron microscopy?
...
In addition to the above, is there perhaps a family history of
any of
the following: |
Medullary carcinoma of the thyroid
NOTE: Always check patient and family for Sipple's MEN-II or MEN-
IIb. |
Is it a cancer arising in the thyroid gland, composed of
relatively
small, highly anaplastic cells that lack lymphocyte markers? |
Undifferentiated ("anaplastic") thyroid carcinoma, small cell
variant |
Is it a cancer arising in the thyroid gland, composed of large,
highly
anaplastic cells? |
Undifferentiated ("anaplastic") thyroid carcinoma, giant cell
variant |
Is it an enlarged parathyroid gland?
Does the patient perhaps have hypercalcemia? |
Parathyroid hyperplasia or parathyroid adenoma
NOTE: You cannot distinguish these unless you have more
information,
i.e., about the other glands. |
Are all four (three, five, however many there are) parathyroid
glands
enlarged?
Does the patient perhaps have hypercalcemia (primary, tertiary
parathyroid hyperplasia) and/or chronic renal insufficiency
(secondary, tertiary parathyroid hyperplasia)? |
Parathyroid hyperplasia
NOTE: Consider checking the patient for Wermer's MEN-I and
Sipple's
MEN-II. |
Is only one of the four (three, five, however many there are)
parathyroid glands enlarged? |
Parathyroid adenoma
Much less likely: Parathyroid carcinoma. |
Is it a single enlarged parathyroid gland, and histology shows
some or
all of these: ...mitotic figures; ...trabecular growth pattern; ...invasion of capsule and/or blood vessels and/or lymphatic vessels?
Is it metastatic cancer with good evidence that the primary is in
the
parathyroid (i.e., a mass these, etc.)? |
Parathyroid carcinoma |
Is it the adrenal cortex of a newborn, and there is no fetal
layer?
And the child is anencephalic? |
Anencephalic adrenal hypoplasia |
Is it the adrenal cortex of a newborn with adrenal insufficiency,
and
the cells are large and bizarre? |
Cytomegalic adrenal hypoplasia |
Is this a patient with several of the following: ...nausea and weight loss; ...low blood pressure; ...weakness and tiredness; ...emotional lability; ...sudden circulatory collapse in a stressful situation? |
Adrenal insufficiency ("Addisonism", "Addison's disease") |
Is it a patient with adrenal insufficiency and increasing skin
pigmentation?
Is it a patient with adrenal insufficiency and you can exhibit
the
principal lesion to be in the adrenals? |
Primary adrenal insufficiency |
Is it a patient with primary adrenal insufficiency, demonstrable
at
least on ACTH stimulation testing, atrophic adrenal cortices
packed
with lymphocytes? |
Autoimmune adrenalitis ("idiopathic Addison's disease") |
Is it an adrenal gland with relatively few, relatively small
cells in
its cortex?
Is it a patient with adrenal insufficiency due to exogenous
glucocorticoids or pituitary failure? |
Adrenal cortical atrophy / secondary adrenal insufficiency
|
Is it adrenals with extensive hemorrhage and perhaps
necrosis? |
Waterhouse-Friderichsen syndrome or birth trauma |
Is the adrenal gland enlarged, primarily by a thickened cortex,
so that
it weighs more than ten grams or so? Does the adrenal cortex exhibit several yellow nodules?
Under the microscope, is the adrenal cortex notably thickened by
endocrine-type cells, with or without abundant cytoplasm, with or
with
out foamy lipid vacuoles, and with or without metaplastic bone
marrow
(sic)? |
Adrenal cortical hyperplasia |
Is this a boy, girl, or woman with virilization and adrenal
hyperplasia? |
Congenital adrenal hyperplasia / adrenal virilism |
Is it a single yellow nodule in the adrenal gland, composed of
benign-
appearing glandular cells, perhaps with hyperchromatic nuclei,
but
without necrosis or metastases?
Does the patient perhaps have: |
Adrenal cortical adenoma
NOTE: Most of these produce no known hormone and no known
syndrome. |
Is it a grossly (large size, necrosis, metastases) or
microscopically
(necrosis, utterly bizarre cells, mitotic figures) malignant
tumor
arising in the adrenal gland, with lipid in the cells and/or
hormone
production and/or no evidence of catecholamine production? |
Adrenal cortical adenocarcinoma |
Is it a round chunk of fat and hematopoietic cells in the adrenal
gland? |
Myelolipoma |
Is it a soft, vascular, very bloody mass in the adrenal, at the
origin
of the superior mesenteric artery, or where there is some
sympathetic
or parasympathetic ganglion? Is it a tumor from the location of an autonomic ganglion, and the cells are large, with abundant pink cytoplasm and perhaps a suggestion of nerve processes?
And does the patient perhaps have most of the following:
Or does the patient perhaps have a personal or family history
of
Did your instructor happen to tell you that the tumor turned a
pretty
mahogany brown when somebody dropped it into chromic acid? |
Pheochromocytoma NOTE: There's no telling the malignant ones from the benign ones until something metastasizes.
NOTE: Consider checking patient and family for Sipple's MEN-II or
MEN-
IIb. |
Is it a soft, gray tumor, arising in or near the adrenals or
along the
sympathetic trunks (or perhaps elsewhere), perhaps with
calcification?
And is the patient a young child? And microscopically, is the tumor composed of cells with very scanty cytoplasm ("small blue cells"), perhaps with Homer-Wright pseudo- rosettes (rings of cells with fibrillary stuff in the middle, as if they were making a neural tube)?
And on electron microscopy, do you perhaps see neurosecretory
granules? |
Neuroblastoma |
Is it a neuroblastoma-like tumor but with Schwann cells and
fibrous
tissue for a stroma, and at least some recognizable ganglion
cells? |
Ganglioneuroblastoma |
Is it a white nodule in the adrenal or retroperitoneum, or along
the
sympathetic chains?
And microscopically, is it composed of fibrous tissue with
embedded
neurons? |
Ganglioneuroma
NOTE: Self-curing neuroblastomas differentiate into
ganglioneuroblastoma and then into ganglioneuromas. |
Is it a thymus gland with germinal centers? |
Thymic hyperplasia |
Is it a tumor of the thymic epithelium, with or without an
admixture of
T-lymphocytes? |
Thymoma
NOTE: You can only tell these are malignant if you see gross
infiltration of nearby structures. |
Is it a tumor arising in the pineal gland, with the
histopathology of a
medulloblastoma or neuroblastoma? |
Pinealoblastoma |
Is it a pineal tumor resembling a seminoma / dysgerminoma,
embryonal
cell carcinoma, choriocarcinoma, and/or teratoma? |
Pineal germinoma |
Is it a pineal tumor composed of various glial and neuronal type
cells? |
Pineocytoma |
Is it furrowed, "weather beaten" skin on an older person?
Is there an amorphous, slightly basophilic appearance to the
upper
dermis? |
Solar elastosis |
Is it "hives" a blotchy, red, slightly elevated acute eruption,
perhaps following exposure to an allergen?
Is it a more enduring case of "hives" in a person with systemic
autoimmune disease, vasculitis, malignant lymphoma, mastocytosis,
celiac disease, or dermatographism? |
Urticaria |
Is it an acute, itchy, at least somewhat oozy-crusty
dermatitis?
Is there accumulation of edema fluid within the epidermis (i.e.,
spongiosis), disrupting its integrity? (Beyond this, the
histopathology may vary some with the cause.) |
Acute eczematous dermatitis
Consider allergic contact dermatitis, irritant dermatitis, atopic
dermatitis, drug eruption, and lots of other things. |
Is it an itchy area of skin that looks chronically inflamed and
on
which the skin lines are exaggerated? Has the patient been
scratching
it a lot?
And on biopsy, do you see acanthosis, hyperkeratosis, and a thick
granular layer? |
Lichen simplex chronicus |
Is it a rash with target lesions? Is it an epidermis apparently being attacked by lymphocytes, perhaps with much apoptosis of the cells of the lower layer?
Does the patient perhaps have herpes simplex, mycoplasma,
leprosy, deep
fungi, typhoid, cancer, lupus, polyarteritis, dermatomyositis,
and/or a
drug reaction (sulfonamide is notorious)? |
Erythema multiforme With fever and systemic involvement: Stevens-Johnson syndrome
With necrosis and loss of much of the epidermis and mucosae:
Toxic
epidermal necrolysis |
Is it inflamed painful, tender bumps in the fat of the lower
leg?
Is it fat with the broad connective septa widened by fibrin and
acute
inflammation, perhaps later with chronic inflammation and even a
few
good granulomas? |
Erythema nodosum |
Is it an inflammatory, necrotizing panniculitis, typically a
single
lesion, that ulcerates? Histologically, does it look like a
vasculitis
is the problem? |
Erythema induratum |
Is it pink plaques on the elbows, knees, scalp, gluteal cleft,
and/or
glans, with a silvery scale? Does peeling the scale produce
punctate
bleeding ("Auspitz's sign")?
Is also there perhaps one of more of the following:
Does skin biopsy show all or most of the following: |
Psoriasis |
Is it chronic, purplish, itchy thickenings on the flexor surface
of the
wrist, the glans, or elsewhere on the skin? Is it a filigree of lines on the buccal mucosa?
Do you see the following on biopsy: |
Lichen planus |
Is it skin with large, more-or-less round, shiny-scaly, red
plaques
with telangiectatic vessels, loss of hairs, and variegated
hypopigmentation and perhaps hyperpigmentation? Do you perhaps
see
little keratin plugs in the follicles if you look very
closely?
Is it a skin biopsy showing most of the following:
Is there a granular deposit of IgG and C3 along the basal lamina
("positive lupus band test")? |
Discoid lupus
NOTE: If the "lupus band test" is positive on uninvolved skin,
the
patient probably also has systemic lupus. |
Is it the familiar "acne" of adolescence, etc., with expanding
sebum-
keratin plugs in follicles with open lumens ("blackheads", "open
comedones") and closed lumens ("closed comedones"), the latter
perhaps
undergoing suppuration?
If someone happened to biopsy this lesion, do you see the keratin
plug
in the follicle, perhaps with surrounding suppuration? |
Acne vulgaris |
Is it a skin disease that tends to spread to any site that has
been
recently injured? |
Koebner phenomenon Consider psoriasis, lichen planus, vitiligo, morphea, others. |
Is it a blistering disease involving the skin and perhaps mucosal
surfaces, with blisters forming where the skin is rubbed
("Nikolsky's
sign")? And on light microscopy, do you see acantholysis with separation of the epidermis just above the basal layer ("suprabasal acantholytic blister"; basal cells remain below as "tombstones")?
And on immunofluorescence, do you see immunoglobulin deposited on
the
desmosomes, i.e., as a network between the epidermal cells? |
Pemphigus vulgaris |
Is it a disease producing warty-blisters on the skin of a
patient,
usually a Central or South American? And on light microscopy, do you see acantholysis with separation of the epidermis most marked in the stratum granulosum?
And on immunofluorescence, do you see immunoglobulin deposited as
a
network between the epidermal cells? |
Pemphigus foliaceus |
Is it a blistering skin disease with separation of the entire
epidermis, including the basal layer, from the basement membrane
("subepidermal non-acantholytic blister")?
And on immunofluorescence, do you see a smooth, linear
immunoglobulin
deposit along the basement membrane (i.e., antibodies against
hemidesmosomes)? |
Bullous pemphigoid |
Is it a urticarial and/or blistering skin disease, cropping up
symmetrically, with extreme pruritis? And on biopsy, do you see acute inflammation of the tips of the dermal papillae? And on immunofluorescence, do you see IgA in the tips of the dermal papillae (autoantibodies against reticulin in anchoring fibrils)?
And does the patient perhaps have gluten enteropathy? |
Dermatitis herpetiformis |
Is it a blistering disease of sun-exposed skin, with subepidermal
blisters and considerable hyaline thickening of the nearby blood
vessels?
Is the patient perhaps an iron-overloaded alcoholic? Is there
perhaps
extra hair over the cheekbones? Are the lesions from the backs
of the
hands or the center of the chest? Does the patient perhaps have
hypertrichosis, photomutilation, (and in the worst cases) a taste
for
blood, and is mistaken for a vampire or werewolf? Etc., etc. |
Porphyria
NOTE: The common one is porphyria cutanea tarda. Dracula and
friends
may have suffered from congenital erythropoietic porphyria. |
Is it a single, deep abscess of hairy skin, perhaps caused by a
staphylococcus? |
Furuncle ("boil") |
Is it a large, deep skin infection with suppuration and multiple
draining sinuses? |
Carbuncle |
Is it a red, non-suppurating, spreading skin infection, perhaps
caused
by a group A streptococcus? |
Cellulitis / phlegmon / erysipelas |
Does the histology show most of the following: ...bumpy epidermal hyperplasia; ...prominent granular layer; ...vacuoles surrounding nuclei of infected cells ("koilocytosis")? And do you recognize the lesion grossly as the familiar wart? And if somebody did electron microscopy, do you see viruses in the nucleus? |
Wart
Depending on the location, this may be "verruca vulgaris",
"condyloma
acuminatum", etc. |
Is it little pruritic skin lesions from which the patient can
express a
curd-like center? Is it a hyperplastic skin lesion containing a crater filled with cells bearing very large, homogeneous, intracytoplasmic viral inclusions? |
Molluscum contagiosum |
Is it honey-colored crusts on the skin?
Is it a skin lesion with neutrophils just under the stratum
corneum?
If you have a gram stain, do you see gram positive cocci among
the
neutrophils? |
Impetigo |
Is the gross picture recognizable to you as one of these: ...ringworm of the scalp or beard; ...tinea corporis, cruris, or versicolor; ...athlete's foot; ...onychomycosis?
Does PAS or silver stain reveal fungi in the dead keratin
layer? |
Superficial fungus infection ("dermatophytosis") |
Is it a "stuck-on", pigmented, crusty lesion on an older person's
skin? Is it multiple, small, dark hyperkeratotic lesions on a black person's face ("papulosa nigra")?
Do you see hyperplasia of the basal cells of the epidermis, which
have
piled up, and produced sharply-demarcated keratin pearls ("horn
cysts")? |
Seborrheic keratosis |
Is it darkening and crusty thickening of the skin of the axillae,
and
perhaps neck and groin? If someone biopsies it, do you see
hyperplasia of the basal cells and excess keratin? |
Acanthosis nigricans |
Is it a rapidly-developing, volcano-shaped lesion with a keratin-
filled crater? Does the dermatologist say it will go away by
itself?
And histologically, do you see hyperplasia of the epidermis,
apparently invading the dermis, but without cytologic atypia? |
Keratoacanthoma |
Is it a cyst beneath the skin or elsewhere, its center filled
with
laminated keratin and its wall composed of stratified squamous
epithelium? |
Epidermoid inclusion cyst |
Is it a cyst beneath the skin or elsewhere, its center filled
with a
mix of keratin and sebum, and its wall resembling the components
of the
pilosebaceous apparatus? |
Pilar cyst ("trichilemmar cyst"; "sebaceous cyst") |
Is it a cyst beneath the skin or elsewhere, its center filled
with a
mix of keratin and sebum, and its wall resembling hairy
epidermis? |
Dermoid cyst |
Is it a cyst beneath the skin or elsewhere, its center filled
with a
mix of keratin and sebum, and its wall made of sebaceous
epithelium? |
Steatocystoma multiplex |
Is it a papillary lesion of the skin, with a fibrous core with
overlying epidermis? |
Fibroepithelial polyp ("skin tag") |
Is it a small, rough, horny-scaly, perhaps slightly pigmented
and/or
shiny-atrophic patch typically on sun-exposed skin of an older
person
(or the palms, if arsenic was a factor)? And on histology, is
there
atypia of the basal layer, which retains squamous features and is
not
invading (i.e., is this "squamous cell dysplasia / carcinoma in
situ")? |
Actinic keratosis ("solar keratosis"; "senile keratosis",
"arsenical
keratosis") |
Is it a skin lesion, especially on sun-exposed hair-bearing skin
of an
older person, perhaps (but not necessarily) rich in pigment? Is
it
perhaps telangiectatic, and if ulcerated, is there a pearly,
rolled
border? And on microscopy, is the lesion an invasive cancer
composed
of cells with scanty cytoplasm but little other evidence of
anaplasia,
no intercellular bridges, and a tendency to form a palisade of
cells
around the edges of the invasive cords? |
Basal cell carcinoma |
Is it a cancer producing any of the following: ...single-cell keratinization; ...good desmosomes between the cancer cells; ...good keratin pearls? Is it located: ...on sun-exposed skin of an older person; ...at the edge of a chronic osteomyelitis sinus or other fistula; ...on the palm of someone who has taken arsenic some time ago? |
Squamous cell carcinoma of the skin
NOTE: The in-situ phase ranges from an actinic keratosis to an
erythematous plaque. |
Is it a fleshy nodule on the skin of an older person, composed of
cells about 15-25 microns across with very little cytoplasm,
neurosecretory
granules and positive staining for neuroendocrine markers? Does
it
look histologically like oat-cell carcinoma of the lung? |
Merkel cell carcinoma
NOTE: Cancer of an atavistic touch receptor |
Is it an epithelial tumor of the skin that looks like it ought to
be a
classic example of something, but you don't find it listed
here? |
Skin adnexal tumor NOTE: Lots of varieties. Get out a real pathology book.
|
Is it a firm-to-hard bump in the dermis, with some
hyperpigmentation of
the overlying epidermis? Does the epidermis (being unattached to
the
lesion) dimple when it is squeezed? On microscopy, do you see a
non-
encapsulated lesion composed of spindle and/or foam cells in
collagen
within the dermis? Is its cut surface perhaps brown or
yellowish? |
Dermatofibroma ("benign fibrous histiocytoma of skin",
"sclerosing
hemangioma")
NOTE: A large, mildly-malignant dermatofibroma a with "pinwheel"
arrangement of spindle cells is called a dermatofibrosarcoma
protuberans. |
Have the melanocytes and melanin disappeared from a region of the
skin, in the absence of other local pathology? |
Vitiligo |
Is it a flat, hyperpigmented skin lesion, less than 1 cm and
probably
one of many, with increased melanin production by melanocytes
which may
be slightly atypical and/or increased in numbers, but not
floridly
malignant? Is the owner perhaps a redhead? |
Freckle ("ephelis") |
Is it the familiar raccoon-eyes "mask of pregnancy", or a similar
lesion in a patient taking phenytoin, or with no known
predisposing
factor? Under the microscope, is there either: ...increased pigmentation of the basal layer; ...pigment incontinence with the dermal papillae packed with melanophages (i.e., melanin-laden macrophages)? |
Melasma |
Is it a flat, hyperpigmented skin lesion under 10 mm, with
hyperplasia
of the melanocytes and perhaps some elongation of the rete
pegs? |
Lentigo |
Is it a darkly-pigmented, perhaps spectacular birthmark with
nevus
cells extending through the dermis and into the fat? |
Congenital nevus |
Is it a pigmented nevus from a young person, with cuboidal and/or
spindly nevus cells at the dermal-epidermal junction and in the
upper
dermis, perhaps showing cellular atypia, but with a tendency to
lose
this atypia and "mature" deeper in the dermis? |
Spitz nevus |
Is it a lightly or darkly pigmented skin lesion which on
microscopy
shows nevus cells confined to the dermis, without "junctional
activity"
(i.e., no clumps of cells at the dermal-epidermal border)? |
Intradermal nevus |
Is it a lightly or darkly pigmented skin lesion which on
microscopy
shows nevus cells distributed primarily in groups along the
dermal-
epidermal junction ("junctional activity")? |
Junctional nevus |
Is it a lightly or darkly pigmented skin lesion which on
microscopy
shows nevus cells both in groups along the dermal-epidermal
junction
and in the deeper dermis? |
Compound nevus |
Is it a benign nevus, perhaps regressing, with depigmentation of
the
surrounding skin? And on microscopy, do you see both nevus and
surrounding skin under attack by lymphocytes? |
Halo nevus |
Is it a group of darkly-pigmented nevus cells with many branches
("dendritic nevus cells"), deep in the dermis? |
Blue nevus |
Is it a junctional nevus with some or all of these features: ...6 mm or more across; ...irregular border; ...variegated pigmentation (i.e., the color is not uniform) ...large clusters of nevus cells at the dermal-epidermal junction, perhaps so large that adjacent nests fuse; ...cytologic atypia of the nevus cells; ...a modest infiltrate of lymphocytes near these nests; ...pigment incontinence and melanophages; ...fibrosis in the upper dermis around the rete pegs?
Is there perhaps a personal or family history of other BK moles
and/or
melanoma? |
Dysplastic nevus ("BK mole") |
Is it a large, flat, pigmented, perhaps variegated lesion on sun-
exposed skin? On microscopy, is it malignant melanocytes only in
radial growth phase with cells exhibiting considerable atypia,
but
mostly growing as individual cells in the basal layer? |
Lentigo maligna melanoma ("Hutchinson's freckle")
|
Is it a pigmented skin lesion, perhaps variegated and/or
irregular, on
sun-exposed skin or elsewhere? On microscopy, is it malignant
melanocytes in groups, perhaps invading the upper epidermis, but
still
in radial growth phase and not invading dermis? |
Superficial spreading melanoma |
Is it a malignant melanoma at the edges of the hairless,
nonpigmented
skin of the palm or sole? |
Acral lentiginous melanoma |
Is it cancer composed of malignant melanocytes anywhere in the
body,
whether in radial or vertical growth phase? Is it positive for
melanin
and/or S100, and do you perhaps find melanosomes on electron
microscopy? |
Malignant melanoma
NOTE: Your instructors probably want you to know both "Clark's
levels"
and "Clark's stages"; don't confuse the two conceptually. |
Is it bone viewed under polarized light, with its lamellae all
parallel? |
Lamellar bone
NOTE: All healthy adult bone is lamellar. |
Is it bone viewed under polarized light, with crisscrossing of
its
fibers? |
Woven bone
NOTE: Normal in kids, most pathologic and healing bone is also
woven. |
Is it a broken bone with the overlying skin and soft tissue
intact? |
Simple ("closed") bone fracture |
Is it a broken bone with the fracture site in communication with
the
outside environment? |
Compound bone fracture |
Is it bone that has been splintered into several pieces? |
Comminuted bone fracture |
Is it a cracked bone, not broken into two separate pieces? |
Greenstick bone fracture |
Is it a "knot" of blood clot, fibroblasts, cartilage, and/or
osteoid at
the site of a fracture? |
Healing bone fracture / callus |
Is it a "knot" of blood clot, fibroblasts, cartilage, and/or
osteoid at
the site of a fracture? |
Pseudarthrosis ("false joint") |
Is he or she a patient who has excessively fragile bones, perhaps
sustaining multiple fractures on being born, or in less severe
cases,
perhaps deformed and very short? Are the teeth perhaps
abnormally
shaped? Do the sclerae perhaps appear blue?
Has the biochemist identified some lesion that interferes with
proper
formation of type I collagen? |
Osteogenesis imperfecta ("brittle bone disease") |
Are the marrow cavities gradually being filled by solid bone as a
result of defective osteoclast resorption? As a result, are the
bones
prone to be radio-dense yet extra-brittle, and is there perhaps
deficient blood cell production? |
Osteopetrosis |
Is this a dwarf with normal rib development, spine and head, but
shortened arms and legs, and perhaps a depressed center to the
face?
If there is a family history, is it autosomal dominant? |
Achondroplasia / achondroplastic dwarfism |
Is it pus in the bone marrow cavity, perhaps also with
granulation
tissue? Is the spongy bone perhaps necrotic (a "sequestrum",
i.e.,
there are no osteocytes in the lacunes)?
Do you perhaps see any of the following: |
Pyogenic osteomyelitis |
Is it caseous necrosis, probably with granulomas, in the bone
marrow?
And you see no fungi, and perhaps an acid-fast stain shows
mycobacteria?
And has the process perhaps resulted in either of the
following: |
Tuberculous osteomyelitis |
Is it periosteal disease with proliferative endarteritis
narrowing
vessels, and abundant plasma cells? |
Syphilitic periostitis |
Is this bone that has lost its matrix, i.e., abnormally thin
cortex,
abnormally rarified spongy bone, as part of a systemic process or
in an
immobile extremity? Is this a compression fracture of a vertebral body in an older person, perhaps producing a "dowager's hump"?
Are the spicules of spongy bone in a histologic section unusually
thin
and perhaps unusually few? |
Osteoporosis |
Is it a mixed picture of osteitis fibrosa cystica
("hyper-parathyroid
bone disease") and osteomalacia, in a patient with longstanding
renal
insufficiency? |
Renal osteodystrophy |
Is this bone from a person with primary, secondary, or tertiary
hyperparathyroidism, and you see masses of fibrous tissue with
osteoclasts, where marrow should be, resorbing bone, leading in
time to
hollowed out "cysts" (misnomer) in the bone?
Is it a random section of adult's bone, without a recent fracture
or
Paget's disease, and you see an osteoclast? (Even seeing one in
a
grown-up, without some other good reason, suggests
hyperparathyroidism.) |
Osteitis fibrosa cystica / Hyper-parathyroid bone disease |
Is it bone from an older person that looks and crumbles like
dried
biscuit? Is it bony spicules with a mosaic pattern of craze-marks? Are they surrounded by a fibrous tissue with excess osteoblasts and osteoclasts?
Does the patient perhaps have any of these: |
Paget's osteitis deformans |
Is part of the bone being replaced by a benign, fibrous tissue
with
metaplastic woven bone? |
Fibrous dysplasia of bone |
Do several bones exhibit fibrous dysplasia ("polyostotic")? In
addition, does the patient exhibit some or all of: ...caf‚-au-lait spots with ragged borders; ...precocious puberty; ...vitamin D resistance; ...various endocrinopathies? And is the illness sporadic, the result of a mutation early in embryonic life, the mutation being lethal to the fertilized egg? And does the research lab notice that cells tend to react to activation of cGMP as if it were cAMP? |
McCune-Albright's disease |
Is new bone forming under the periosteum of the distal ends of
long
bones, hand bones, foot bones, and finger and toe bones?
And does the patient probably have lung cancer, or some other
kind of
cancer or some other severe longstanding lung disease, or else
cirrhosis? |
Hypertrophic osteodystrophy |
Is it a lytic lesion in the metaphysis of a long leg bone of a
child?
Histologically, do you see a cellular mass of fibroblasts without
bone
formation? |
Fibrous cortical defect ("non-ossifying fibroma")
|
Is it a hard bump of dense bone jutting off the skull or jaw,
perhaps
into a nasal sinus? |
Osteoma |
Is it a round, painful lesion of bone, with a lytic center
composed of
fibrous tissue with miniature bony trabeculae, and a sclerotic
rim
composed of thick bony trabeculae? |
Osteoid osteoma |
Is it a non-painful, lytic lesion of bone composed of miniature
bony
trabeculae? |
Osteoblastoma |
Is it a malignant tumor in which the cancer cells themselves are
making osteoid? (There are several histologic variants.)
Did it perhaps (but not necessarily) arise in one of these
settings: |
Osteosarcoma |
Is it a bony bump off the metaphysis of a long bone, with a
cartilage
cap?
Is it one of dozens of similar lesions from a patient diagnosed
with
one of the autosomal-dominant "osteochondromatosis" syndromes or
Gardner's syndrome? |
Exostosis ("osteochondroma") |
Is it chunks of mature cartilage in a vascular stroma, popping up
as a
"bone tumor"? Does the patient also perhaps have lots of these cartilage bumps ("Ollier's syndrome", not hereditary) over part of the body?
Or does the patient also perhaps have lots of these plus lots of
hemangiomas ("Maffucci's syndrome, autosomal dominant)? |
Chondroma |
Is it a chondroma arising inside of a bone? |
Enchondroma |
Is it a mixed mess of mature cartilage, dense fibrous tissue, and
loose myxoid fibrous tissue, perhaps with some cellular atypia,
often
(but not necessarily) at the knee of an older male teen? |
Chondromyxoid fibroma |
Is it a bone tumor composed primarily of little, uninucleate
chondrocytes? Do you also perhaps see any of these: ...calcification; ...benign giant cells; ...good cartilage matrix; ...figures; ...hemorrhage; ...necrosis?
Is it perhaps (but not necessarily) an apparently destructive
lesion
from the knee of a male teen? |
Chondroblastoma |
Is it a cartilage-based tumor in bone with either multinucleate
chondrocytes and/or multiple chondrocytes in one lacune and/or
obviously anaplastic chondrocytes?
Did it perhaps (but not necessarily) arise in the pelvis of an
older
man, or in a patient with an enchondromatosis syndrome or from an
exostosis? |
Chondrosarcoma |
Is it a primary bone tumor, not leukemia-lymphoma, composed of
anaplastic cells with scanty cytoplasm, typically filling a
marrow
cavity, and with no tendency to make a dense collagenous stroma?
And
are the tumor cells rich in glycogen?
Is the patient perhaps a teenaged male? Is the trademark
t(11:22)
translocation present? |
Ewing's sarcoma
NOTE: Many similar tumors bear neuroendocrine markers, plus the
t(11:22) translocation. Ask your instructor. |
Is it a primary, soft, vascular, often bloody, locally
destructive
spindle-cell bone tumor with abundant benign osteoclasts?
Is the tumor perhaps (but not necessarily) from the knee? |
Giant cell tumor of bone ("osteoclastoma")
NOTE: Hemorrhage, necrosis, mitotic figures are all poor
predictors of
behavior. |
Is it age-related changes in the hip, knee, or first
metacarpophalangeal joints? Is it "Heberden's nodes" alongside the distal interphalangeal joints of the fingers?
Is the cartilage thinned, frayed, cracked, eroded, overly
basophilic,
and/or missing live chondrocytes? In the underlying bone, is
there
eburnation (i.e., thickened from constant rubbing) and/or
microcyst
formation? As a result, are the sides of the articular surfaces
growing outward as bumps ("spurs", "osteophytes")? |
Osteoarthritis / degenerative joint disease |
Is it arthritis beginning in the small joints of the hands and
feet,
and perhaps progressing to the familiar mutilating changes? Is it markedly thickened synovium, with hyperplastic, layered-up synovial lining cells, and infiltrated by lymphocyte, plasma cells, and macrophages? (In other words, is this "pannus"?) As the disease progresses, does the joint undergo destruction?
Do you perhaps also find, elsewhere in the patient: |
Rheumatoid arthritis |
Is it a nodule, up to 2 cm across, with a central necrotic mass
of
fibrinoid, rimmed by a palisade of epithelioid histiocytes? And
surrounding this, are there lymphocytes and plasma cells? |
Rheumatoid nodule |
Is it pus, perhaps also with granulation tissue as the process
develops, in a joint? |
Suppurative arthritis |
Is it a highly destructive arthritis with caseous necrosis? Can
no
organism be visualized or cultured except mycobacterium? |
Tuberculous arthritis |
Is it uric acid crystals from an inflamed joint?
Is it a tophus, i.e., a mass of uric acid crystals encased in a
granuloma? |
Gout |
Is it calcium pyrophosphate crystals from an inflamed joint?
Is it a knee or other joint with chalky crystal of calcium
pyrophosphate or hydroxyapatite on its articular surfaces? |
Pseudogout / calcium crystal deposition arthritis |
Is it a proliferation of synovial cells and macrophages in a
tendon
sheath? Are there perhaps abundant giant cells? |
Giant cell tumor of tendon sheath / nodular tenosynovitis |
Is it a proliferation of synovium and macrophages covering an
articular surface (usually the knee), with hemorrhage and
destruction
of the joint? |
Pigmented villinodular synovitis |
Does the muscle perhaps appear normal on H&E section, but special
stains reveal the type I and type II fibers to be grouped
together
rather than at random? |
Type grouping of muscle fibers
NOTE: Denervation-reinnervation is the cause. |
Are the individual muscle fibers decreased in cross-sectional
area? Do you see angular muscle fibers?
Are the type II fibers of a couch potato, person on
glucocorticoids, or
other type patient substantially smaller, and perhaps more
angular,
than the type I fibers? |
Atrophy of muscle fibers
NOTE: Don't mistake a golgi tendon organ for atrophy. |
Has a segment of a muscle fiber become hypereosinophilic (i.e.,
stains
red instead of pink) and has lost its cross-striations? |
Degeneration of muscle fibers |
Is this apparent muscle fiber cells with basophilic cytoplasm, a
rounded-up, pale-staining nuclei no longer stuck on the
sarcoplasmic
membrane, and visible nucleoli? |
Regenerating muscle fibers |
Is it contraction bands (q.v.) in skeletal muscle? And if this
isn't
Duchenne's muscular dystrophy, are we perhaps looking at the edge
of a
muscle biopsy near the surgeon's cuts? |
Hypercontraction of muscle fibers |
Is this muscle fibers with sarcomeres arranged circumferentially
in a
ring under the sarcolemma, surrounding the properly-oriented
sarcomeres deep in the fibers?
Does this patient perhaps have myotonic dystrophy? |
Ring muscle fibers |
Is it muscle fibers that appear to have clefts, as if they
cracked? |
Split muscle fibers |
Is this muscle exhibiting group atrophy of its fibers as the
primary
lesion?
Does the finding of type grouping on special stains confirm
denervation-reinnervation? |
Denervation atrophy of muscle
|
Is this a younger boy with weakness and pseudohypertrophy of the
muscles, or such a boy grown to be wheelchair-bound by age 16?
And on muscle biopsy (which isn't always a good idea), do you
see: |
Duchenne's muscular dystrophy |
Is it a Duchenne-like picture, but the boy is less severely
affected,
and can walk on his sixteenth birthday? |
Becker's muscular dystrophy |
Is this a patient who first loses the ability to whistle, then
loses
mass in the deltoids, pectorals, shoulder girdle, and upper arm
muscles? Is muscle biopsy nondiagnostic?
Does the family history perhaps suggest autosomal dominant
inheritance? |
Facioscapulohumoral muscular dystrophy |
Does he or she have weakness and, distinctively, difficulty
letting go
of doorknobs, jar lids, and handshakes? On muscle biopsy, do you see a lot of ring fibers, central nuclei, and disorganized chunks of non-striated actin and myosin in the cytoplasm? Does he or she also perhaps have a small chin, frontal balding, a "tapir-nose", and personality problems?
Does this autosomal-dominant disease get worse from generation to
generation (Sherman's paradox)? |
Myotonic muscular dystrophy |
Are there rods of Z-band material running down the centers of the
muscle fibers? |
Nemaline myopathy |
Is this an autosomal dominant disease in which the central
regions of
the type I fibers lack myofilaments and energy-producing
enzymes? |
Central core myopathy |
Does he or she have unusually well-developed muscles even with
little
resistance training, but complains of muscle cramps in cold
weather? |
Myotonia congenita |
Is this a disease featuring "ragged red fibers", the ragged red
areas
being packed with worthless mitochondria? Are the worthless
mitochondria perhaps packed with "parking lot" crystalloids? |
Mitochondrial myopathy ("Kearns-Sayre myopathy", AZT myopathy,
others) |
Is this an acquired syndrome of weakness relieved by injection of
edrophonium? Does the patient perhaps have thymic hyperplasia
and/or a
thymoma?
Do you see, perhaps (but not necessarily), clusters of
lymphocytes
around the motor end plates in the muscles? |
Myasthenia gravis |
Is this a tumor of the tongue or elsewhere, composed of polygonal
cells packed with dPAS-positive granules (phagolysosomes with
junk
inside them), S100-positive, and inducing hyperplasia in any
nearby
stratified squamous epithelium? |
Granular cell tumor |
Is this a sarcoma with cells positive for any of these: ...alpha-1 protease inhibitor (antitrypsin); ...alpha-1 antichymotrypsin; ...lysozyme; ...factor XIIIa? Is this a sarcoma, and the cells are making cartwheels-pinwheels ("storiform arrangement"), myxoid areas, or areas that remind you of a granuloma?
Do you think this is a sarcoma, but it doesn't look like any of
the
sarcomas you know? (If so, "MFH" is a good bet.) Is your
instructor
perhaps talking eagerly about "facultative fibroblasts"? |
Malignant fibrous histiocytoma
|
Is it an encapsulated mass of mature fat, typically from under
the
skin?
Does it perhaps (but usually not) contain prominent blood vessels
and/or fibrous septa and/or marrow? |
Lipoma |
Is it a sarcoma from deeper in the body, with some of these
features: ...looks like a lipoma, but has some anaplasia ("well- differentiated liposarcoma"); ...myxoid gross and microscopic appearance, with a prominent network of vessels and a few lipoblasts ("myxoid liposarcoma"); ...highly cellular, small-cell sarcoma with some vacuolated lipoblasts ("round cell liposarcoma"); ...super-ugly lipoblasts, at least a few bearing several fat vacuoles ("pleomorphic liposarcoma")? |
Liposarcoma
|
Is it a sarcoma from deeper in the body, perhaps somewhere where
there
is skeletal muscle, and you see some of these features: ...primitive cells, strap cells (elongated, eosinophilic cytoplasm, maybe cross-striations), tennis-racket cells, spider cells (central nucleus indented by huge glycogen vacuoles); this is an "embryonal rhabdomyosarcoma"; if there is a cambium layer, it is a "sarcoma botryoides" ...as the above, but a tougher call ("pleomorphic rhabdomyosarcoma"); ...undifferentiated cells with scanty cytoplasm, in clusters surrounded by fibrous alveolus-like walls ("alveolar rhabdomyosarcoma")? Does this cancer stain positive for desmin and/or myoglobin?
Does electron microscopy of this cancer show good sarcomeres? |
Rhabdomyosarcoma
|
Is it a tumor of interlacing smooth-muscle bundles as in the
familiar
uterine "fibroid"? Is it perhaps (but not necessarily)
uncomfortable? |
Leiomyoma |
Is it a smooth-muscle tumor with several mitotic figures? |
Leiomyosarcoma |
Is it a well-differentiated spindle-cell tumor making scanty
collagen,
but with the spindle cells arranged in a herringbone pattern? |
Fibrosarcoma |
Is it an apparent sarcoma, not arising from a mesothelial
surface, with
a "biphasic" mix of spindle-cell and gland-like areas? |
Synovial sarcoma
NOTE: Monophasic versions exist. Don't worry about them. |
Is it an irregular thickening of the palmar fascia, perhaps
entrapping
one or more finger tendons? |
Palmar fibromatosis ("Dupuytren's contracture") |
Is it an irregular thickening of the fascia of the penis, perhaps
occluding the urethra and/or causing curvature of the erect
penis? |
Penile fibromatosis ("Peyronie's disease") |
Is it a lesion composed of collagen-producing fibroblasts without
atypia, but locally invasive? Is the site perhaps the abdominal
muscles during or just after pregnancy, or in a big skeletal
muscle, or
anywhere in a patient with Gardner's syndrome? |
Aggressive fibromatosis ("desmoid") |
Is it a rapidly-growing lesion composed of fibroblasts that look
like
the familiar tissue-culture kind, without atypia, but apparently
invading muscle and other nearby tissues and probably with
mitoses and
hemorrhage? |
Nodular fasciitis ("pseudosarcomatous fasciitis")
NOTE: Leave this lesion alone, it's benign. |
Is it a scleroderma-like lesion of fascia with abundant
eosinophils?
Is it a syndrome of rhabdomyolysis-myositis in which eosinophils
invade the muscle and bloodstream? And did the patient take
tainted
"health-food store" tryptophan? |
Eosinophilic fasciitis / eosinophilia-myalgia syndrome |
Is it skeletal muscle being replaced by fibrous tissue which
undergoes
metaplasia into bone, either at a single site of injury, or in
many
different locations for no apparent reason? |
Myositis ossificans |
Is he or she a trim individual with a large heart and low resting
pulse, with lots of mitochondria in the skeletal muscles and
impressive physical endurance? Does this person train by making
muscles contract and expand repeatedly to the limits of their
metabolic
capacity, though not against great resistance? |
Aerobic athlete |
Is he or she a physically strong individual, with increased
diameter of
the type II fibers, and who trains by making muscles contract
only a
few times per day against maximal resistance? |
Strength athlete |
Is he (or even she, heaven forbid) a strength athlete with
several of
the following: ...rapid, really impressive increase in muscle mass (gee whiz!); ...tell-tale testicular atrophy and sterility; ...greatly increased LDL and/or lowered HDL; ...cholestasis; ...gynecomastia (men) / amenorrhea and hirsutism and guy-smell (women; you have been warned); ...acne getting much worse; ...accelerated masculine-type hair loss; ...impotence (men) or increased libido (either sex); ...aseptic necrosis of a hip; ...hepatic adenoma, focal nodular hepatocyte hyperplasia, or hepatocellular carcinoma; ...personality changes, and not for the better? |
Strength athlete on anabolic steroids NOTE: You'll see a lot more of these specimens than you will "nodular fasciitis". Around 1,000,000 Americans are doing this stuff while you read this.
NOTE: Consider yourselves properly cautioned. |
Is the calvarium mostly or entirely absent, and the forebrain
represented only by neuroglial nubbins? |
Anencephaly |
Is there a defect in the bones of the spine, allowing the dura,
but not
the spinal cord, to herniate out under the skin? |
Meningocele |
Is the brain of a newborn generally well-formed, but a portion is
herniating out through a hole in the skull? |
Encephalocele |
Is there a defect in the bones of the spine, allowing both dura
and
spinal cord to herniate out under the skin? |
Meningomyelocele |
Is the cerebellar vermis ("roof of the fourth ventricle", or
whatever)
congenitally absent, or at best represented by inert glial scar
("cyst")? |
Dandy-Walker syndrome |
Is this a brain with: ...elongated cerebellar tonsils that hang through the foramen magnum; Is there also (usually) hydrocephalus and a problem with the formation of the spine (meningocele, meningomyelocele)? |
Arnold-Chiari malformation ("Chiari II malformation") |
Is this an adult's brain weighing less than 900 gm, or a child's
brain
that is proportionally undersized, the result of a birth defect?
In
addition, are the gyri perhaps not all there, but the brain is
otherwise well-formed? |
Microcephaly |
Is it a brain with a single cerebral hemisphere, lacking the
usual
midline structures of the prosencephalon?
Is the patient perhaps a cyclops? |
Holoprosencephaly |
Is this a brain with some or all of the limbic system missing?
In its
mildest form, is the brain normal except for no olfactory bulbs
or
tracts? |
Arhinencephaly |
Is the brain more or less well-formed except that the corpus
callosum
is partly or completely missing, perhaps with a lipoma or dermoid
cyst
at the site of a partial defect? Does the patient perhaps have
alexithymia? |
Agenesis of the corpus callosum |
Is it a brain with no development of gyri, and there are only
four,
rather than six, layers to the cortex? |
Agyria ("lissencephaly") |
Is it a brain with just a few big, ill-formed gyri, and there are
only
four, rather than six, layers to the cortex? |
Pachygyria |
Is it a brain with too many gyri, and there are only four, rather
than
six, layers to the cortex? |
Polymicrogyria |
Is it a cleft in the brain that does not actually cause a
discontinuity in the cortex, though it severely deforms it? |
Schizencephaly |
Is it a cleft in the brain that goes so deep that it reaches the
ependyma? |
Encephaloclastic porencephaly |
Is it a congenital "hole in the brain", perhaps the result of a
fetal
stroke? |
Porencephaly |
Is it massive destruction of part or all of the cerebrum, perhaps
as a
result of failure of the carotid arteries to develop properly, or
infection of the fetus by CMV or toxoplasmosis? |
Hydranencephaly |
Is it loss of brain tissue, most severe deep in one or more sulci
of
the unborn child or newborn, probably as a result of
ischemia? |
Ulegyria |
Is it a "marbled" pattern seen in the putamen and caudate from
ischemia or kernicterus around the time of birth? |
Etat marbr‚ ("status marmoratus", "marbled state") |
Is it necrosis surrounding the ventricles of a child's brain,
worst at
the angles, resulting from hypoxic-ischemic injury (the
periventricular white matter being one watershed area of a
child)? |
Periventricular leukomalacia |
Is this a swollen neuron body with lysis of the rough endoplasmic
reticulum ("Nissl substance") except under the cell membrane? |
Central chromatolysis ("axonal reaction")
NOTE: In a few locations, this is normal. Otherwise, it means
the axon
was severed. |
Is this a neuron with its nucleus small and dark, and its
cytoplasm
shrunken and slightly hypereosinophilic? |
Red necrotic neuron
NOTE: Think of hypoxia, circulatory arrest, hypoglycemia. |
Are the neurons bloated with some abnormal granular material,
with the
nucleus pushed to one side? |
Intra-neuronal storage disease |
Is this a round, perhaps laminated, eosinophilic mass in the
cytoplasm
of a neuron (most often, a pigmented neuron of the substantia
nigra),
composed of neurofilament proteins? |
Lewy body |
Is it a weakly basophilic mass filling most of the cytoplasm of a
big
neuron? Does it stain strongly with the Bielschowsky silver
method,
which shows it as a tangled mess of filaments? Does electron microscopy show the filaments to resemble twisted ribbons? Does the lab confirm that the predominant component is altered tau protein?
Does the patient have Alzheimer's disease (or is at least old),
or
dementia pugilistica, or progressive supranuclear palsy, or
Parkinsonism after Von Economo's influenza encephalitis, or Guam
ALS? |
Neurofibrillary tangle |
Does it appear on H&E as a bubbly neuron? Does the Bielschowsky
silver stain show it up nicely, as granules in the neuronal
cytoplasm
surrounded by clear apparent vacuoles? Is the granule also rich
in
altered tau protein? Does the patient perhaps (probably) have
Alzheimer's disease? |
Granulovacuolar degeneration |
Is it a barrel-shaped intracytoplasmic inclusion that is seen
best on
Bielschowsky silver staining? |
Pick body |
Is it an eosinophilic rod on a neuron's dendrite? Does the
patient
also have Alzheimer's disease? |
Hirano body |
Is it a dilated portion of an axon, visible as a round or oval
structure in the neuropil? And has the patient perhaps suffered
trauma (notably, diffuse axonal injury) or an infarct, or
something
else that disrupts axons? |
Axonal spheroid |
Is this an astrocyte with an extremely large, extremely
hyperchromatic
nucleus? And does the patient (probably) have progressive
multifocal
leukoencephalopathy? |
Alzheimer I astrocyte |
Is this an astrocyte with a swollen, edematous-looking nucleus,
making
it conspicuous in the neuropil? And did the patient die with
liver
failure and elevated blood ammonia? |
Alzheimer II astrocyte |
Is this an astrocyte with abundant, eosinophilic cytoplasm, and a
large nucleus typically with a visible nucleolus? Is it one of a
group of similar cells activated for repair? |
Gemistocyte |
Is it a PTAH-positive red rod in an astrocyte cytoplasm? |
Rosenthal fiber |
Is it a basophilic, glycogen-positive sphere in the neuropil,
especially under the pia and ependyma, especially in older
people? |
Corpora amylacea |
Is it a slightly-basophilic, glycogen-positive, daisy-shaped mass
in a
neuron? Does the patient (probably) have myoclonus epilepsy? |
Lafora body |
Is it an activated microglial cell, with its nucleus appearing as
a
"rod" in the neuropil? |
Rod cell |
Is it a lipid-laden microglial cell / macrophage in an area in
which
the brain has undergone necrosis? |
Gitter cell |
Is it a group of microglia ("microglial nodule") surrounding a
dead
neuron? |
Neuronophagia |
Is it an increase in the volume of cerebrospinal fluid from any
cause,
for any reason? Is it a child, with sutures not yet fused, with a tremendously enlarged head but normal-sized face, optic nerves stretched so the eyes look downward ("setting sun")?
Is it an adult with the poorly-understood syndrome of "normal
pressure
hydrocephalus", with apraxia of gait, dementia, and incontinence,
which
responds to CSF shunting? |
Hydrocephalus |
Is it an increase in the volume of spinal fluid in some or all of
the
ventricular system because the flow of spinal fluid is blocked
somewhere along its course? |
Communicating hydrocephalus |
Is it an increase in the volume of spinal fluid because of
overproduction (i.e., choroid plexus papilloma) or deficient
resorption (i.e., scarring around the arachnoid villi, etc.) |
Non-communicating hydrocephalus |
Are the ventricles of the brain simply enlarged because of brain
"atrophy" (i.e., loss of brain cells for whatever reason)? |
Hydrocephalus ex vacuo |
Has the cingulate gyrus been pushed, as a result of localized
edema
and/or a space-occupying lesion, underneath the falx? In
addition to
the deformity, has the anterior cerebral artery perhaps been
compromised? |
Cingulate herniation
|
Has the cerebellar tonsil been pushed, as a result of a shift in
intracranial contents due to generalized edema or an expanding
lesion,
out the foramen magnum? Has the medulla probably been crushed in
the
process? |
Cerebellar tonsillar herniation |
Has the uncus of the temporal lobe been pushed downward, as a
result of
localized edema and/or a space-occupying lesion, into the
tentorial
notch? In addition to the deformity, has there perhaps been
compromise
of the ipsilateral third nerve ("blown pupil"), contralateral
third
nerve (in "Kernohan's notch"), and/or ipsilateral posterior
cerebral
artery? |
Tentorial uncal herniation |
Has the skull been massively fractured and/or opened by surgery,
and is
edematous brain protruding? |
Trans-calvarial herniation |
Is this a brain with some or all of the cortex so swollen that
the
sulci have been greatly narrowed and the gyri flattened against
the
skull? |
Cerebral edema |
Is there excess fluid between the brain cells? Does water run
from the
cut surfaces of this edematous brain?
Is the clinical setting a bacterial infection, recent trauma, a
recent
infarct, cancer, or lead poisoning? |
Vasogenic cerebral edema
NOTE: Nothing subtle, just like leaky vessels anywhere else. |
Is there excess water actually inside the brain cells? Despite
this
brain being obviously edematous, does little or no water run from
the
cut surfaces?
Is the clinical setting ischemia, perhaps a stroke-in-progress or
after cardiac arrest? |
Cytotoxic cerebral edema |
Is this edema primarily in the white matter immediately
surrounding the
ventricles, in hydrocephalus? |
Interstitial cerebral edema |
Is it thick pus, perhaps with some organization, covering the
brain?
Was a classic bacterium probably identified as the etiologic
agent? |
Acute pyogenic meningitis |
Is it an acute inflammation of the arachnoid primarily with
lymphocytes? If an etiologic agent has been found, was it a
virus? |
Acute lymphocytic meningitis |
Is it dense white debris encasing the circle of Willis? On
microscopy, is there the familiar caseous necrosis of TB, and
perhaps
granulomas and/or mycobacteria as well? |
Tuberculous meningitis |
Is it an opalescent thickening of the arachnoid, with fibrosis
and a
plasmacytic, obliterative vasculitis, perhaps (but not often
nowadays)
producing infarcts? |
Meningovascular syphilis |
Is it involvement of the meninges by thickly-encapsulated yeasts,
probably with a positive India-ink test? Do the yeasts perhaps
grow
down into the Virchow-Robin spaces and eventually expand them,
producing Swiss-cheese brain? |
Cryptococcal meningitis |
Does the patient have serologic evidence of syphilis, and any of
these: ...manic behavior or other psychosis, progressing to horrible insanity; ...brain atrophy; ...loss of neurons and their replacement with astrocytes ("windswept cortex"); ...lots of rod cells in the cortex? |
General paresis / paretic neurosyphilis |
Does the patient have serologic evidence of syphilis, and any of
these: ...loss of sensation in the extremities, especially proprioception; ...loss of deep tendon reflexes; ...Charcot joint deformities; ...Argyll-Robertson pupils that accommodate without reacting; ...lightning pains; ...loss of axons and myelin in the dorsal roots; ...loss of myelin and axons in the dorsal columns? |
Tabes dorsalis |
Is it a brain infection with a preponderance of lymphocytes,
plasma
cells, and macrophages? Are glial cells and neuronophagia
perhaps
prominent? |
Viral encephalitis |
Is it a meningoencephalitis with widespread necrosis of brain
tissue
and an impressive lymphocytic vasculitis? Is there perhaps
currently
an epidemic? |
Arbovirus encephalitis |
Is it an acute necrotizing viral encephalitis, most severe in the
temporal lobes? Under the microscope, do you perhaps see swollen
oligodendroglia cell nuclei, with some perhaps bearing
intranuclear
Cowdry A herpes-type inclusions? |
Herpes encephalitis |
Is it an infection limited to the anterior horns of the spinal
cord,
with cells as in viral encephalitis, and neuronophagia of
anterior horn
cells?
Is this the spinal cord of a known "polio" survivor, with absent
anterior horn cells? |
Poliomyelitis |
Is this an encephalitis with neurons bearing intracytoplasmic,
oval,
eosinophilic Negri bodies? |
Rabies |
Is this the spinal cord of an HIV-positive person, with
lipid-laden
macrophages especially in the lateral columns? |
AIDS vacuolar myelopathy |
Is this brain from a person with a dementing disorder of several
years' duration, and histology shows lymphocytes, plasma cells,
and
prominent eosinophilic inclusions in oligodendroglia and perhaps
also
in astrocytes and/or neurons?
Does electron microscopy show measles virus-like particles in
those
inclusions? Did the lab perhaps identify measles virus acting as
a
slow virus? |
Dawson's subacute sclerosing panencephalitis ("SSPE") |
Is this the brain of an immunosuppressed person who suffered from
progressive dementia, and have portions of the white matter, and
perhaps also the gray, lost their shiny white myelin?
And on microscopy, do surviving oligodendroglia at the edges of
the
lesions have nuclei that are grossly enlarged, with blobby
intranuclear inclusions? And deep in the lesions, are there
bizarre
hyperchromatic astrocyte ("Alzheimer type I") nuclei? |
Progressive multifocal leukoencephalopathy ("PML") |
Is the brain cortex almost devoid of neurons, and filled instead
with
bubbly spaces in the neuropil? Did the patient have an inexorably-progressive dementing and movement disorder?
Are there perhaps (but by no means necessarily) some amyloid
plaques,
especially in the cerebellum? |
Spongiform encephalopathy / prion disease (includes
Creutzfeldt-Jakob
disease, kuru, veterinary diseases) |
Is it a necrotizing brain lesion in someone who is
immunocompromised,
and toxoplasma "cysts" are in evidence at the edges of the
expanding
necrosis?
Is it a necrotizing and calcifying lesion of the brain of an
unborn
child, and there are no CMV cells or other evidence of CMV
infection? |
Cerebral toxoplasmosis |
Is it a swollen, violaceous brain examined several days following
an
episode of near-drowning, cardiac arrest, or profound
hypoglycemia?
Histologically, do you see mostly "red necrotic" neurons? Is it a brain with a profoundly thinned cortex, nearly or totally devoid of neurons? Is it brain, not quite so severely involved, but with necrosis and loss of the pyramidal cell layers ("laminar necrosis") in most areas of the cortex?
Is it the familiar pattern of "watershed infarcts" of the brain,
particularly involving the parasaggital cortex? |
Ischemic ("hypoxic", "hypoglycemic") encephalopathy |
Is it any portion of the cortex, following generalized hypoxia,
hypoperfusion, or hypoglycemia, or local ischemia, with necrosis
and
loss of the pyramidal cell layers ("laminar necrosis")? |
Laminar necrosis |
Is it a linear, parasaggital infarct in the area between the
middle and
anterior cerebral arterial distributions, following an episode of
hypotension or hypoxia? |
Watershed infarct ("border zone infarct") |
Is it softening and eventual lysis of a portion of brain in the
distribution of a blood vessel? In this setting, is the gray-white junction blurred? Are there petechiae, or perhaps more extensive hemorrhage as blood finds its way back into the damaged vessels? Microscopically, do you see dying brain cells, perhaps hemorrhage, and usually some foamy macrophages ("gitter cells")?
Is this a portion of brain, after a known or unknown "stroke",
which
has liquified and been transformed into a cavity without
significant
collagenous scarring, with a rim of fibrillary gliosis, and with
perhaps some lipid-laden macrophages as permanent residents? |
Cerebral infarct |
Is it an expansile hematoma deep in the brain substance,
typically the
basal ganglia, surrounded by considerable edema? Do you perhaps
see
blood pigments in the surrounding tissue, blood forced up the
Virchow-
Robin spaces of nearby small vessels, or rupture into a
ventricle?
Is it a hemosiderin-pigmented slit in the deep brain substance,
surrounded by fibrillary gliosis and hemosiderin-laden
macrophages?
(This is the site of an old hemorrhage which the patient
survived.) |
Intracerebral hemorrhage |
Is it a little aneurysm without good elastica in its wall,
arising from
the circle of Willis or nearby (most often, the anterior
communicating
artery)? Did it perhaps rupture? |
Berry aneurysm |
Is it a tangle of vessels deep in the brain substance? Has there
perhaps been hemorrhage here? |
Cerebral arteriovenous malformation |
Is it a mass of fresh blood or hemosiderin pigment in the
subarachnoid
space? Was the bleeding site a berry aneurysm or a cerebral
arteriovenous malformation? |
Subarachnoid hemorrhage |
Is it a brain with many small infarcts deep in the brain? Did
the
patient perhaps have high blood pressure and/or a shower of
micro-
emboli? |
Lacunar infarcts |
Is this the brain of a patient with both longstanding
hypertension and
progressive dementia, simulating Alzheimer's disease? And is
there
loss of myelin and axons in the centrum semiovale? And is there
severe
hypertensive arteriolar sclerosis on microscopy? |
Binswanger's subcortical leukoencephalopathy |
Is this a patient with severe high blood pressure, with headache
and
convulsions and probably papilledema?
Is it the brain from such a patient, and the principal pathologic
finding is cerebral edema? |
Hypertensive encephalopathy |
Is it a lens-shaped mass of blood forced between skull and dura
following fracture of the skull which severed the middle
meningeal
artery? Was the patient perhaps knocked out, regained lucidity,
then
sank into coma? |
Epidural hematoma |
Is it a massive hemorrhage underneath the dura, from avulsion of
the
bridging veins? |
Acute subdural hematoma |
Is it a fibrous, hemosiderin-stained membrane overlying the
cerebral
hemispheres, the site of an old bleed which organized and is now
shunting blood away from the cortex? Is the patient perhaps an
older
person with brain atrophy which stretched the bridging veins,
which
were avulsed by some mild trauma? |
Chronic subdural hematoma |
Is it a bruise of the brain following trauma? Is it a cone-shaped, hemosiderin-pigmented area of obvious brain damage underlying the site of a blow ("coup contusion")? Is it hemosiderin pigmentation and loss of the lower portions of the prefrontal lobes, as a result of one or more episodes of falling onto the back of the head ("contrecoup contusion")?
Is it hemosiderin pigmentation and loss of tissue where the
temporal
lobes overlie the ridge of the petrous temporal bone, following
one or
more episodes of a blow to the head ("contrecoup contusion")? |
Cerebral contusion |
Is it a brain with petechiae in the middle of the corpus
callosum? Is it a brain, normal by CT scan and perhaps nearly-normal appearing at gross autopsy examination, but from a patient who sustained a head injury and never regained normal mentation?
Is it a section of brain from such a patient, with axonal
spheroids and
perhaps even clearly ruptured axons? Is there perhaps also
localized
hemosiderin pigmentation especially in the corpus callosum (where
the
shearing forces come together), and/or foam cells and microglial
cells
where axons have been disrupted? |
Diffuse axonal injury |
Is it a section of brain with pink (active) or yellow-gray (old)
plaques of sclerosis (lost oligodendroglia and myelin, increased
astrocytes) especially around the ventricles?
Microscopically, do you see demyelinization beginning around
vessels
and expanding to become the grossly visible plaques? And are the
axons
preserved? |
Multiple sclerosis |
Is this a one-time-only demyelinating disease, with loss of
myelin
beginning around the little veins, with a lymphocytic
infiltrate?
Did it follow an infection or immunization ("acute disseminated
encephalomyelitis", etc.), and usually take a relatively benign
course? Or is it the very lethal, hemorrhagic-necrotizing
disease
which follows a cold ("acute necrotizing hemorrhagic
leukoencephalitis")? |
Perivenous encephalomyelitis including "acute disseminated
encephalomyelitis" and "acute necrotizing hemorrhagic
leukoencephalitis". |
Is this the brain of an adult with progressive dementia, and you
see
some of these things: ...senile plaques (i.e., areas of abnormal, silver-stainable dendrites, surrounding a chunk of amyloid); ...neurofibrillary tangles; ...granulovacuolar degeneration; ...Hirano bodies; ...amyloid in the cerebral vessels ("congophilic angiopathy")? |
Alzheimer's disease
NOTE: The best place to look is in the hippocampus. Stay tuned
for a
better definition of the disease. |
Is it changes identical to Alzheimer's, but less numerous,
perhaps
confined to the hippocampus, and the patient isn't demented? |
Alzheimer's senile change |
Is this a brain with selective, impressive atrophy of the
prefrontal
and temporal lobes?
Is this a brain with swollen, edematous-looking neurons and Pick
bodies as the predominant histologic changes? |
Pick's disease |
Is it a section of brain in which the head and body of the
caudate have
virtually disappeared?
Is it a section of caudate nucleus in which the neurons have
mostly
disappeared? |
Huntington's disease |
Is it a section of substantia nigra with loss of most of the
pigmented
neurons?
Is it several pigmented neurons in the substantia nigra, most
bearing
one or more Lewy bodies? |
Idiopathic Parkinson's disease |
Is it pigmented neurons in the substantia nigra, perhaps
decreased in
number, bearing neurofibrillary tangles? |
Post-encephalitic Parkinson's disease |
Are the caudate and putamen atrophic, with loss of neurons? Are
neurons also lost from the substantia nigra, but you see no Lewy
bodies or neurofibrillary tangles here? |
Striatonigral degeneration |
Is it Parkinsonism, perhaps with the abnormal anatomy of
idiopathic
Parkinsonism or striatonigral degeneration, plus loss of the
intermediolateral column neurons which give rise to the
sympathetic
nervous system? As a result, does the patient have profound
autonomic
disturbances including orthostatic hypotension? |
Shy-Drager disease
NOTE: More talked-about (whenever a patient is "orthostatic")
than
seen. |
Is there variable loss of neurons in the inferior olives,
cerebellar
cortex, and basis pontis? Is there perhaps a hereditary
tendency? |
Olivopontocerebellar atrophy |
Is this a nervous system with a small spinal cord with loss of
much of
the white matter, loss of neurons on the dentate nucleus, and
atrophy
of much of the cerebellum?
Was the patient a male with a familial disease with ataxia,
cranial
nerve dysfunctions, and probably death from a cardiomyopathy? |
Friedreich's ataxia |
Is this an older person with loss of anterior horn cells, motor
neurons of cranial nerve, and/or upper motor neurons, without
other
pathology? |
Amyotrophic lateral sclerosis / motor neuron disease |
Is this the brain of a prizefighter exhibiting widespread
cortical
atrophy and neurofibrillary tangles in neurons? |
Dementia pugilistica |
Is this an extremely floppy baby with a neurogenic atrophy and
progressive weakness leading to death in childhood? Do studies
show
this is autosomal recessive? Is this the nervous system of a child with profound thinning of the motor roots? On histologic examination, are most of the muscle fibers profoundly atrophic, with a few groups enlarged? Is type grouping, of course, also present?
On histologic examination of the spinal cord, are the anterior
horn
cells almost all gone? |
Werdnig-Hoffman infantile progressive spinal muscular atrophy |
Is this an older person with progressive muscle denervation
weakness
and atrophy and loss of anterior horn cells? Do studies show
this is
genetically programmed? |
Kugelberg-Welander progressive spinal muscular atrophy |
Is this the spinal cord from a patient with B12 deficiency from
any
cause, with loss of myelin worst in the dorsal columns (look for
foam
cells), and eventually disruption of the axons and gliosis?
Is this a B12 deficient patient with a sensory neuropathy with
paresthesis and ataxia? |
Subacute combined degeneration of the cord |
Is this an alcoholic or other patient with thiamine deficiency
with
acute cerebellar ataxia, confusion and nystagmus, and/or with
chronic
non-intentional confabulation and/or problems moving the eyes?
Is this the brain from such a patient, and you see hemosiderin
pigmentation and/or gliosis in the mammillary bodies and/or the
dorsomedian nucleus of the thalamus next to the third
ventricle? |
Wernicke-Korsakoff syndrome |
Is this radiation-induced or chemotherapy-induced necrosis of the
deep
white matter of the hemispheres and/or basis pontis, perhaps with
calcification of the remnants of the axons, and with negligible
inflammatory reaction? |
Iatrogenic leukoencephalopathy ("radiation encephalopathy",
"chemotherapy encephalopathy") |
Is this a rhomboid-shaped area of loss of myelin centered on the
basis
pontis? And did the patient have his or her hyponatremia, from
whatever cause, corrected too rapidly by the doctor? |
Central pontine myelinolysis |
Is this an autosomal recessive or mitochondrially-transmitted
(yes)
disease with widespread necrosis, vascular proliferation, and
gliosis
in the brain, leading to death in childhood?
And has the lab perhaps identified a deficiency in cytochrome C
(from
whatever enzyme problem) as the underlying cause? |
Leigh's subacute necrotizing encephalomyelopathy |
Is it a demyelinating disease that spares the subcortical fibers?
Is
the disease hereditary, usually with death in childhood? Does frozen section stained with quickie-stain show an accumulation of metachromatic material?
And has the lab perhaps identified deficiency of arylsulfatase A
as the
underlying problem, and galactosyl sulfatide as the accumulating
substance? |
Metachromatic leukodystrophy |
Is it a hereditary demyelinating disease with histiocytes around
blood
vessels, packed with galactocerebroside? |
Krabbe's globoid cell leukodystrophy
|
Is he a patient with an X-linked syndrome of adrenal
insufficiency and
demyelination? Does the lab find excess very long-chain fatty
acids in
the blood? Does electron microscopy demonstrate the
characteristic
inclusions in brain macrophages and the adrenal glands? |
Adrenal leukodystrophy |
Is it a liquefaction and dilatation of the central portion of the
cervical spinal cord, interrupting the spinothalamic tract that
carries pain and temperature sensation from the arms to the
brain? |
Syringomyelia |
Is it slit-like, fluid-filled lesions in the brainstem, similar
to
syringomyelia? |
Syringobulbia |
Is it an self-limited, ascending paralysis following viral
infection,
usually followed by full recovery? In those rare cases when
pathologic
material is available for examination, do you see lymphocytes
plus
destruction and phagocytosis of myelin in the motor nerve
roots? |
Guillain-Barr‚ syndrome ("acute idiopathic polyneuritis") |
Is it a progressive neurogenic atrophy of the muscles of the
legs,
producing the striking "upside-down champaign bottle legs"? |
Charcot-Marie-Tooth peroneal muscular atrophy |
Is it a benign spindle cell tumor on a nerve, with richly
cellular
("Antony A") areas containing parallel sets of palisaded cells
("Verocay bodies"), and myxoid ("Antony B") areas? Are the
arterioles
hyalinized here? And do the involved nerve's axons run along the
edge
of, rather than through, the tumor? |
Schwannoma ("neurilemmoma")
NOTE: "Acoustic neuromas" are really schwannomas. |
Is it a tumor that thickens a nerve trunk, and is composed of
loosely-
arranged, often wiggly spindle cells? And do the involved
nerve's
axons run through the tumor itself? |
Neurofibroma |
Is it a malignant tumor that thickens a nerve trunk, and the
patient
probably has Von Recklinghausen's neurofibromatosis? |
Neurofibrosarcoma |
Is it a pale gray, infiltrated, poorly-circumscribed tumor of the
brain substance or spinal cord, without necrosis?
And histologically, do you see one of these (highly variable)
patterns: |
Astrocytoma
NOTE: Vascular endothelial proliferation or more than 1 mitotic
figure
in ten high power fields makes it "anaplastic", which is bad. |
Is it a pale gray, fairly well demarcated, soft brain tumor,
usually
with calcium flecks?
And histologically, do you see: |
Oligodendroglioma |
Is it a sharply-demarcated CNS tumor, usually in the spinal cord,
with
benign-appearing cells, often triangular, against a fibrillary
background? Does the tumor perhaps form "ependymal rosettes" (little neural tubes and/or rings around blood vessels)?
Does PTAH staining perhaps show blepharoplasts? |
Ependymoma |
Is it a spherical, firm-to-calcified bump attached to the
ventricular
lining, usually an autopsy curiosity? Histologically, do you see
clumps of ependymal cells in a fibrillary background? |
Subependymoma |
Is it a massive, poorly-circumscribed, widely-necrotic, widely-
hemorrhagic brain tumor, microscopically with pseudopalisading of
tumor cells and much vascular proliferation? Or are at least
most of
these features present? |
Glioblastoma multiforme |
Is it monoclonal lymphocytes proliferating in the brain, perhaps
in a
person with AIDS or some other immunosuppressive problem? |
Cerebral lymphoma |
Is this a tumor at the site of the choroid plexus, and almost
perfectly reduplicating this structure? |
Choroid plexus papilloma |
Is it a simple cyst, filled with gelatinous fluid, next to (and
probably obstructing) the foramen of Monro? |
Colloid cyst of third ventricle |
Is it a white mass arising around the cerebellar vermis, perhaps
spreading up and down the neuraxis, and composed of very
primitive
cells with very little cytoplasm?
Do the cells perhaps show both glial (GFAP+) and neural (stains,
a few
Homer-Wright pseudo-rosettes) differentiation? (Or the tumor may
do
one, or neither.) |
Medulloblastoma |
Is it a sharply-circumscribed round mass, compressing but not
invading
the brain, and arising typically over the sphenoid ridge or the
falx?
Microscopically, do you perhaps see one or more of these: |
Meningioma |
Is it a brain with several (typically) sharply-circumscribed
round
masses, typically at the gray-white junctions, surrounded by
considerable edema?
Is it cancer cells detected in the meninges, perhaps at the
autopsy of
a patient with mysterious cranial nerve palsies and a normal CT
scan? |
Metastases to the brain |
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