Ed Friedlander, M.D., Pathologist

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Welcome to Ed's Pathology Notes, placed here originally for the convenience of medical students at my school. You need to check the accuracy of any information, from any source, against other credible sources. I cannot diagnose or treat over the web, I cannot comment on the health care you have already received, and these notes cannot substitute for your own doctor's care. I am good at helping people find resources and answers. If you need me, send me an E-mail at scalpel_blade@yahoo.com Your confidentiality is completely respected. No texting or chat messages, please. Ordinary e-mails are welcome.

I am active in HealthTap, which provides free medical guidance from your cell phone. There is also a fee site at www.afraidtoask.com.

If you have a Second Life account, please visit my teammates and me at the Medical Examiner's office.

Freely have you received, give freely With one of four large boxes of "Pathguy" replies.

I'm still doing my best to answer everybody. Sometimes I get backlogged, sometimes my E-mail crashes, and sometimes my literature search software crashes. If you've not heard from me in a week, post me again. I send my most challenging questions to the medical student pathology interest group, minus the name, but with your E-mail where you can receive a reply.

Numbers in {curly braces} are from the magnificent Slice of Life videodisk. No medical student should be without access to this wonderful resource.

I am presently adding clickable links to images in these notes. Let me know about good online sources in addition to these:

Freely have you received, freely give. -- Matthew 10:8. My site receives an enormous amount of traffic, and I'm still handling dozens of requests for information weekly, all as a public service.

Pathology's modern founder, Rudolf Virchow M.D., left a legacy of realism and social conscience for the discipline. I am a mainstream Christian, a man of science, and a proponent of common sense and common kindness. I am an outspoken enemy of all the make-believe and bunk that interfere with peoples' health, reasonable freedom, and happiness. I talk and write straight, and without apology.

Throughout these notes, I am speaking only for myself, and not for any employer, organization, or associate.

Special thanks to my friend and colleague, Charles Wheeler M.D., pathologist and former Kansas City mayor. Thanks also to the real Patch Adams M.D., who wrote me encouragement when we were both beginning our unusual medical careers.

If you're a private individual who's enjoyed this site, and want to say, "Thank you, Ed!", then what I'd like best is a contribution to the Episcopalian home for abandoned, neglected, and abused kids in Nevada:

I've spent time there and they are good. Write "Thanks Ed" on your check.

Help me help others

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Especially if you're looking for information on a disease with a name that you know, here are a couple of great places for you to go right now and use Medline, which will allow you to find every relevant current scientific publication. You owe it to yourself to learn to use this invaluable internet resource. Not only will you find some information immediately, but you'll have references to journal articles that you can obtain by interlibrary loan, plus the names of the world's foremost experts and their institutions.

Alternative (complementary) medicine has made real progress since my generally-unfavorable 1983 review. If you are interested in complementary medicine, then I would urge you to visit my new Alternative Medicine page. If you are looking for something on complementary medicine, please go first to the American Association of Naturopathic Physicians. And for your enjoyment... here are some of my old pathology exams for medical school undergraduates.

I cannot examine every claim that my correspondents share with me. Sometimes the independent thinkers prove to be correct, and paradigms shift as a result. You also know that extraordinary claims require extraordinary evidence. When a discovery proves to square with the observable world, scientists make reputations by confirming it, and corporations are soon making profits from it. When a decades-old claim by a "persecuted genius" finds no acceptance from mainstream science, it probably failed some basic experimental tests designed to eliminate self-deception. If you ask me about something like this, I will simply invite you to do some tests yourself, perhaps as a high-school science project. Who knows? Perhaps it'll be you who makes the next great discovery!

Our world is full of people who have found peace, fulfillment, and friendship by suspending their own reasoning and simply accepting a single authority that seems wise and good. I've learned that they leave the movements when, and only when, they discover they have been maliciously deceived. In the meantime, nothing that I can say or do will convince such people that I am a decent human being. I no longer answer my crank mail.

This site is my hobby, and I do not accept donations, though I appreciate those who have offered to help.

During the eighteen years my site has been online, it's proved to be one of the most popular of all internet sites for undergraduate physician and allied-health education. It is so well-known that I'm not worried about borrowers. I never refuse requests from colleagues for permission to adapt or duplicate it for their own courses... and many do. So, fellow-teachers, help yourselves. Don't sell it for a profit, don't use it for a bad purpose, and at some time in your course, mention me as author and William Carey as my institution. Drop me a note about your successes. And special thanks to everyone who's helped and encouraged me, and especially the people at William Carey for making it still possible, and my teaching assistants over the years.

Whatever you're looking for on the web, I hope you find it, here or elsewhere. Health and friendship!


More of Ed's Notes: Ed's Medical Terminology Page

Perspectives on Disease
Cell Injury and Death
Accumulations and Deposits
What is Cancer?
Cancer: Causes and Effects
Immune Injury
Other Immune
HIV infections
The Anti-Immunization Activists
Infancy and Childhood
Environmental Lung Disease
Violence, Accidents, Poisoning
Red Cells
White Cells
Oral Cavity
GI Tract
Pancreas (including Diabetes)
Adrenal and Thymus
Nervous System
Lab Profiling
Blood Component Therapy
Serum Proteins
Renal Function Tests
Adrenal Testing
Arthritis Labs
Glucose Testing
Liver Testing
Spinal Fluid
Lab Problem
Alternative Medicine (current)
Preventing "F"'s: For Teachers!
Medical Dictionary

Courtesy of CancerWEB

Learning Objectives

You should know this handout, which contains the essential content of the corresponding sections of a good pathology text, at the recall level. I am not kidding. My handouts are as clear as mud, and you owe it to yourself to use a real book for elucidation. The following structured objectives will help you as you master this material.

Explain the scope of pathology as a discipline. Recognize it as a physician's skill and activity as much as a body of knowledge. Explain how pathology integrates the study of disease at:

Recognize the major causes of failure in "Pathology" at the medical school level.

Briefly explain we say pathology is (or should be) a science.

Review how to distinguish science from cultural attitudes, junk science, aphorisms, pseudoscience, and politics. Give some examples from your own life-experience of ways in which politics adversely impacts on human health.

Briefly discuss the philosophic problems involved in defining "the cause of a particular disease".

Define, correctly use, and recall (given the definition) the following ubiquitous pathology words:

Distinguish the different kinds of tissue samples that you will obtain for examination by pathologists.

Define hypoxia, and distinguish "ischemic", "hypoxic", "anemic" and "histotoxic" hypoxia, giving a full list of the causes of each. Describe the different effects of hypoxia on various tissues, and tell in considerable detail how we think hypoxia damages cells reversibly and irreversibly. Briefly cite other important things that damage cells, including hydrolytic agents, immune injury, free radical injury, and apoptosis triggers.

Explain what free radicals are, sketch and name the most important species, and explain in detail how and when they are generated, how they do damage, and how they are finally squelched. Mention the situations in which free radical injury is important clinically. Mention other chemical reactions that injure cells.

Define and correctly use "necrosis", and distinguish the various categories of necrosis (coagulation, liquefaction, enzymatic fat necrosis, caseous necrosis, apoptosis). Tell when you are likely to see each. Briefly review the mechanisms of apoptosis from your previous work in cell biology. Tell how you know a cell is dead. Explain why necrosis is not always visible when ischemia has caused sudden death. Explain how and when enzymatic fat necrosis occurs, mention the settings for liquefaction necrosis, and list four infections characterized by caseous necrosis. Briefly describe the various forms of gangrene.

Describe the basic biology of lysosomes in health and disease. Mention other important ultrastructural features of cells that may be altered in disease. Give the sizes of cytoskeletal elements, including various types of intermediate filaments that distinguish different cells. Name the syndromes that result from their malfunction, and the known toxins that affect them.

Define, correctly use, and supply (given the definition) the following terms:

Give definitions and examples of each of the following, and recognize its presence in a description or photo as applicable:

Be sure you can recognize each of the following, grossly and/or microscopically, as applicable:

Have some sense of what various colors and consistencies will mean in gross specimens.

Ground rule: Here, and on all of my handouts, an asterisk (*) indicates a word, sentence, paragraph, or block of text is non-testable. Paragraphs positioned in outline form underneath a starred paragraph are, of course, not testable either, but PICTURES are. However, don't be surprised if you need some of this information for USMLE/COMLEX, roundsmanship, or even "real life". -- ERF

About These Notes

"Ed's notes" are sequenced after "Big Robbins" and are intended as lecture-helpers for my own students. Other students seem to like them, and they can be especially useful to users of the superb Slice of Life collection.

Nobody's lecture notes are substitutes for reading a good, solid textbook like "Big Robbins", "Rubin & Farber", "Chandrasoma", or others. And of course, nobody's lecture notes are a complete, authoritative guide to clinical practice, or (heaven forbid) your own physician's advice to you. Be wise, and use these notes appropriately.

I don't know what your destiny will be, but one thing I do know: the only ones among you who will be really happy are those who have sought and found how to serve.

      -- Albert Schweitzer MD, Ph.D

Don't take life too serious. It ain't nohow permanent.

      -- Walt Kelley, "Pogo"

Medicine, to produce health, must study disease, and music, to produce harmony, must study discord.

      -- Plutarch

Oh, death has ten thousand several doors
For men to take their exits....

      -- John Webster, The Duchess of Malfi (17th century)

Our lives are filled with joys and strife,
And what is death but part of life?
Will come the day that we must die,
And leave behind those learning why.

      -- "The Pathology Blues" (Class of '98)

To fear death is nothing other than to think onesself wise when one is not. For it is to think one knows what one does not know. No man knows whether death may not even turn out to be the greatest of blessings for a human being; and yet people fear it as if they knew for certain that it is the greatest of evils.

      -- Socrates
It is the unknown we fear when we look upon death and darkness, nothing more.

      -- Albus Dumbledore

We are accustomed to speak of "disease entities" as though they had an independent, individual existence and could be recognized as friends -- or better, perhaps, as enemies. This is obviously one of those abstractions that do violence to the reality of the concrete situation, for there is no disease apart from the patient. The disease is the change produced in the patient by a pathological process. Diagnosis involves the observation of the patient as he is, and also a reconstruction in imagination of the patient as he was, before he was afflicted. The disease is the difference between these two pictures. But this, also, is an abstraction.

      -- Thomas Addis, M.D.

If the patient has all of the risks laid out, as well as all of the benefits, very well-controlled studies have shown the patient tends to choose low-tech, low-cost treatments and is satisfied with the result, no matter what it is, because he chose it.

      --C. Everett Koop, M.D.,
      Chronicle of Higher Education,
      July 1, 1992

Nobody cares how much you know until they know how much you care.

      -- Truism about doctoring

We have to remember that in the end, we humans aren't really taught much; we learn. Most of our learning happens when we are doing. No instructor can place a funnel in your ear and pour knowledge into your head. The most that your instructor can do is demonstrate, explain, and establish attainable goals. The rest is up to you.

      --Jerry A. Eichenberger, "Your Pilot's License" (the aviation classic)

Knowledge makes you vain, education makes you humble.

      -- Hans G. Creutzfeldt, M.D.

Those that know, do. Those that understand, teach.

      -- Aristotle (often misquoted)

As is our pathology so is our practice... what the pathologist thinks today, the physician does tomorrow.

      -- Sir William Osler, M.D.

It's not so much that I relish pressure. I just don't fear it.

      -- Joe Montana

Education is hanging around until you've caught on.

      -- Robert Frost

A man who dares to waste one hour of time has not discovered the value of life.

      -- Charles Darwin

Don't get diseases in the first place, schmo.

      -- Dan Matthews

        Director of Campaigns for People for the Ethical Treatment of Animals
        responding to a question about animal research for treating disease; USA Today, July 27, 1994

American Osteopathic College of Pathologists, Inc.
12368 NW 13th Court Pembroke Pines Florida 33026
Phone 305-432-9640 Free student memberships available

Video: Dr. Robin Fraser talks about being a pathologist
A Medical Career -- Why Not Pathology?
Day in the Life -- Anatomic Pathology -- Dr. Adrienne Morey

KCUMB Students
"Big Robbins" -- Cell Injury
Lectures follow Textbook


Cell Injury and Cell Death
Taiwanese pathology site
Good place to go to practice

Cell Growth Differentiation Regulation and Adaptation
Taiwanese pathology site
Good place to go to practice

Cell Injury and Repair
Photo Library of Pathology
U. of Tokushima

Cell Injury / Inflammation / Repair
Iowa Virtual Microscopy
Have fun

Adaptation and Accumulations
Iowa Virtual Microscopy
Have fun

Necrosis I
From Chile
In Spanish

Necrosis II
From Chile
In Spanish

Necrosis III
From Chile
In Spanish

Necrosis IV
From Chile
In Spanish



{19409} slice of life hooked up to a computer

Cramming is the worst thing you can do, because the minute you get into it, you forget it.

Can you love anyone without making him work hard? Can you do your best for anyone without educating him?

Top row: Achondroplasia (considered desirable in some cultures), baldness-hirsutism (considered attractive or unattractive), Becker's nevus, cross-dressing (stigma, unwanted compulsion, and/or source of enjoyment), deafness (many deaf resent being called handicapped, especially where sign language is widely spoken; this was intensely politicized in the late 1990's as some "multiculturalists" / "advocates for the deaf" tried very hard to prevent young children from obtaining cochlear implants), Ehlers-Danlos (the unusual joint structure may confer superior musical ability, as with Paganini), homosexuality (once a "disease", now mainstream)

Bottom row: Gilbert's disease (an abnormal lab finding with no health consequences), hemochromatosis (fatal if neglected, but offers advantages), left-handedness (carries a tremendous stigma in some cultures, where the left-handed go to great lengths to conceal their "disease"), myotonia congenita, serial killer ("They look just like everybody else" -- Wednesday Addams), dissatisfied straight who'd like to be "bi" -- some adults are now asking psychiatrists for help with this (J. Homo. 15: 7, 1988), XYY "stereotype of the karyotype".

      My own favorite example is William Blake, the great English artist, poet, and humanitarian thinker.

      Blake's "visions" and "voices" strongly suggest schizophrenia, and sometimes they terrified and baffled him. His contemporaries considered that Blake's "genius" and his "madness" (both of which were obvious) must be part of the same process.

      But even today, I don't think any reasonable person would consider Blake "diseased" or "disabled".

      In fact, there's now a considerable amount of talk about schizophrenia, which is a polygenic process with some environmental modification, being the result of natural selection for genes promoting human creativity (Proc. Biol. Sci. 22: 2801, 2009).

The impact of disease on humankind is tremendous. The subject is never "just academic". Each of us will have some first-hand experience with the content of a "pathology" course.

Decomposed body
Tom Demark's Site

Decomposed body
Tom Demark's Site

THE TESTABLE STUFF ON THIS HANDOUT STARTS HERE. Scientific, evidence-based medicine is based around the concept of discrete diseases. This is the approach that works. In today's world, only the charlatans and the fools deny that there are many distinct, identifiable diseases with varying causes, or complain that studying disease objectively makes physicians care less about "whole persons".

PATHOLOGY is often called "the science of disease", and this is a fair definition. By custom, NOSOLOGY means the actual semi-science of naming diseases (for example, in coding diagnoses for paperwork).

    The Greek word PATHOS actually covers a range of meanings from "experience" to "the human condition" to "suffering", while NOSOS ("noxious", "nausea") is the word for "disease" / "physically sick". So Virchow's pathology considers more than just the disease; we consider whatever human factors are involved, too.

Rudolf Virchow
disease, and
social conscience

However, THERE ARE ONLY A HANDFUL OF UNDERLYING MECHANISMS OF DISEASE (the "disease processes"). The body responds to life's hazards in stereotyped ways. These are the subject matter of GENERAL PATHOLOGY (i.e., the stuff up through "Neoplasia/Infections/Immunopathology/Fluid-Hemodynamic"). You'll need to remember them well; they are the template onto which you will place your knowledge of disease.

In contrast to general pathology, SYSTEMIC PATHOLOGY concerns itself with specific diseases that involve the various organ systems. You can use your general pathology knowledge to predict the contents of a chapter in systemic pathology. ANATOMIC PATHOLOGY is the business of making diagnoses by examining tissues, while CLINICAL PATHOLOGY is concerned with the rest of the things done by the clinical lab, i.e., blood banking, clinical hematology, clinical chemistry, clinical microbiology and maybe molecular pathology. FORENSIC PATHOLOGY is a subspecialty under anatomic pathology, dealing with medicolegal issues, especially questionable deaths.

Ice Man -- Famous Neolithic find
National Geographic
Warning: Spyware! (7/6/08)


Skin necrosis
Brown recluse spider bite

Skin necrosis
Brown recluse spider bite

Skin necrosis
Brown recluse spider bite

{07447} carbon monoxide suicide; notice cherry-red color; the blackening of the lips is drying, and the epidermis has slipped off the chin; both indicate a post-mortem interval of a few days.

{01909} radiation necrosis of the brain (Think: this must be toxic/metabolic rather than traumatic or vascular, since you can see that it limits itself to one particular tissue type, the white matter)


{17369} laminated "myelin figures" in cell injury; electron micrograph ("mb"="myelin bodies") (NOTE: despite what anyone else may tell you, these do not prove that the cell is injured irreversibly)

Reversible Cell Injury
From Chile
In Spanish

Myelin figures
Chinese pathology site

Myelin figures
Acute muscle cell injury
KU Collection

{17366} calcium precipitate within mitochondria

{17368} break in cell membrane, irreversible injury

{17374} nuclear pyknosis (arrows); be sure you can tell a pyknotic nucleus from a live lymphocyte nucleus
{17379} dead renal tubular epithelial cells (within lumen of live tubule)

Necrosis, nuclear changes
Don't worry about the type of necrosis.
WebPath Photo

Find pyknosis and karyorrhexis



{07020} carbon tetrachloride toxicity to liver, gross (widespread cell death shows as yellow, in the centers of the lobules)
{07022} carbon tetrachloride toxicity to liver, microscopic (widespread hepatocyte loss; note the paler centrilobular areas where nothing is left except hepatic endothelial cells)

{10658} snake and snake-bit foot

Fer-de-lance snakebite
Tissue necrosis
Wikimedia Commons



{19358} hydropic change in epidermis in acute contact dermatitis (perhaps poison ivy)

Hydropic change
Urbana Atlas of Pathology

{08357} fatty liver, gross (yellow, felt greasy; you would want to see the histology to make sure of the diagnosis)
{38782} fatty change in hepatocytes, oil red O stain; note that lipid vacuoles, being hydrophobic, are sharply demarcated from the rest of the cytoplasm

{07195} putrefied corpse from the woods
{07021} putrefied corpse from the pond; the tongue is swollen because of gas production postmortem

Billy Crystal as the
gravedigger in "Hamlet"

Coagulations necrosis
Proximal renal tubule

Coagulation necrosis.
Kidney infarct.
WebPath Photo

Mercury poisoning
Striking coagulation necrosis of proximal tubules
KU Collection

Coagulation necrosis.
Kidney infarct.
WebPath Photo

Coagulation necrosis.
Adrenal infarct.
WebPath Photo

Coagulation necrosis.
Spleen infarct.
WebPath Photo

Toxic epidermal necrolysis
Necrosis of the epidermis

{39659} Necrosis of the hip, gross specimen with crumbling bone (Bo Jackson's disease)
{05956} Focal necrosis of hepatocytes. A glycogen-is-dark-red counterstain here makes the live hepatocytes red, dead hepatocytes more pink
{08828} Widespread necrosis of hepatocytes; they're gone from most of the field, all that is left is endothelial cells and Kupffer cells; there is a central vein in the center of the picture
{13320} Massive necrosis of the liver (limp liver; nothing is left in the lobules except endothelial cells and reticulin)
{49266} Massive necrosis of the liver ("yellow atrophy"); we would want a histologic picture to confirm our gross impression
{13322} Massive necrosis of the liver with loss of most hepatocytes, histology, in fatal hepatitis
{16952} Necrosis of renal papillae (orange-yellow; the bright yellow at the bottom is kidney fat)
{09578} Neuron, newly-dead ("red neuron")
{10571} Renal cortical necrosis (note yellow color)
{17389} Coagulation necrosis of renal tubules (left side)

{05961} apoptotic hepatocyte ("Councilman body") in hepatitis B (shrivelled, hypereosinophilic, separated from its neighbors)

{06642} contraction band necrosis in heart
{06651} contraction band necrosis in heart (there are also neutrophils)

Contraction Bands
Recent Heart Attack
Johns Hopkins

Contraction bands.
Necrotic heart. Find them.
WebPath Photo

{17399} old liquefactive necrosis, brain, gross
{17400} old liquefactive necrosis, brain, gross

Brain infarct
This will liquefy eventually
WebPath Photo

Brain infarct
This will liquefy eventually
WebPath Photo

Liquefaction necrosis
Brain infarct
WebPath Photo

Liquefaction necrosis
Brain infarct
WebPath Photo

Liquefaction necrosis
Pus pockets in the lung
WebPath Photo

Liquefaction necrosis
Pus pockets in the liver
WebPath Photo

{17404} enzymatic fat necrosis, gross; patches of white calcium stearate
{17403} enzymatic fat necrosis, microscopic (right side); calcium imparts the blue tinge
{08348} enzymatic fat necrosis, microscopic (right side)

Enzymatic fat necrosis
White flecks
WebPath Photo

Enzymatic fat necrosis

WebPath Photo

Enzymatic fat necrosis

KU Collection

Caseous necrosis
TB -- it does look like cheese
WebPath Photo

Caseous necrosis
WebPath Photo

Caseous necrosis
TB granuloma
WebPath Photo

Caseous necrosis
Mycobacterial lymphadenitis

Autopsy lung
KU Collection

        This is a distinctive type of "necrosis" seen in diseases in which there is an intense immune reponse. Details are poorly understood. You'll usually see it in certain granulomatous diseases, notably tuberculosis and certain fungal infections (coccidioidomycosis, blastomycosis, and histoplasmosis -- you'll learn these later).

          The cells appear to be undergoing mass apoptosis (I predicted this in 1986; confirmation came from immunostaining Eur. J. Immunol. 27: 3182, 1997; Infect. Immun. 65: 298, 1997; and most recently J. Clin. Path. 61: 366, 2008). This makes sense -- and also explains why caseous necrosis tends to be white rather than yellow (as in coagulation and liquefaction necrosis). In a mummified apoptotic cell, there's less separation of lipid and water than in coagulation necrosis, so there's no lipid phase to be yellow.

          It is now well-established that cell-mediated immunity against the tubercle bacillus is essential for, and immediately precedes, the appearance of caseous necrosis (Antimicrob. Agents Chemother. 47: 833, 2003).

          Update on the component of the tubercle bacillus that causes caseation: Am. J. Path. 168: 1249, 2006.

        But despite "Big Robbins", don't expect there will always be a nice granuloma walling off the caseous debris -- especially TB in the AIDS-and-homelessness era!

{08187} renal TB, good caseous necrosis (right side, left is normal)
{17395} pulmonary TB, caseous necrosis of the lung, gross
{17396} pulmonary TB, caseous necrosis of the lung, micro (all is crumbly; on the left the nuclei are lost indicating that it is more advanced)

      GANGRENE ("gangrenous necrosis") is not a separate kind of necrosis at all, but a term for necrosis that is advanced and visible grossly. If there's mostly coagulation necrosis, (i.e., the typical blackening, desiccating foot that dried up before the bacteria could overgrow), we call it DRY GANGRENE. If there's mostly liquefactive necrosis (i.e., the typical foul-smelling, oozing foot infected with several different kinds of bacteria), or if it's in a wet body cavity, we call it WET GANGRENE.

        Exactly how anthrax toxin produces tissue injury is being worked out. It includes an "edema factor" that causes cells to ooze their contents, and perhaps this is why surface anthrax presents a black, dehydrated, dead "eschar". Anthrax toxin: Nature 414: 225, 2001, Sci. Am. 286(3): 48, 2002.

{17392} dry gangrene
{25451} dry gangrene
{25452} dry gangrene
{48075} dry gangrene
{48076} dry gangrene
{25453} early gangrene
{25454} wet gangrene (bacteria-rich)
{25455} gangrene of the toe, relatively early
{17393} gangrene of the bowel ("wet")
{10655} infarct of hand following embolus to brachial artery
{38590} gangrene of the fingers

Mostly wet
WebPath Photo

Mostly dry
WebPath Photo

Mostly dry
WebPath Photo

Synergistic bacterial gangrene
Progressive post-operative
necrotizing lesion

Gangrene of the bowel
Urbana Atlas of Pathology

Inoculation site
KU Collection

Foot Gangrene
Australian Pathology Museum
High-tech gross photos

        BACTERIAL GANGRENE occurs when the primary problem is infection by one or two strains of bacteria, and widespread tissue necrosis occurs in short order. Examples:

          CLOSTRIDIAL GANGRENE (including "gas gangrene"), a dread complication of dirty, blood-deprived wounds. The clostridia digest tissue enzymatically and rapidly, often transforming it into a bubbly soup, usually too fast for inflammation to develop. Minutes count.

          SYNERGISTIC GANGRENE after surgery, a mixed infection with staphylococci and streptococci

          ULCERATIVE GINGIVITIS ("trench mouth"), caused by overgrowth of anaerobes in the mouths of stressed people with dubious oral hygiene.

          NOMA, necrosis of the lower face and/or female genitalia, seen only in people who are immunocompromised (usually from severe malnutrition; Am. J. Trop. Med. 78: 539, 2008).

          * FOURNIER'S GANGRENE, bacterial gangrene of the scrotum (the dreaded "black sack disease" -- no joke; get seen at a specialty hospital J. Urol. 182: 2742, 2009.)

          Fournier's gangrene

      CAVITATION results from removal of necrotic material (i.e., draining a huge abscess, coughing up caseous debris in tuberculosis, physiologic removal of debris in a cerebral infarct, etc.)

      FIBRINOID NECROSIS is a time-honored term for damage to the walls of arteries that allows plasma proteins to seep into, and precipitate in, the media (some pathologists call this "insudation"). This is a particularly unwholesome situation. You'll learn the common causes (notably malignant hypertension and type III / immune complex immune injury) later. It's hard to be sure that anything here is really dead, but at least the intima must have been damaged.

{01917} fibrinoid necrosis, blood vessel, following radiation (fibrinoid is pink)
{53545} fibrinoid necrosis, blood vessel, in a vasculitis syndrome (fibrinoid is the pink center ring)

      * GUMMATOUS NECROSIS is, for our purposes, coagulation necrosis seen in granulomas in syphilis. I've seen this only in study-sets.

      * NECROBIOSIS is a curious term for necrosis of fibroblasts within still-intact dense fibrous tissue. It's characteristic of two lesions -- necrobiosis lipoidica and granuloma annulare.

    NOTE: If a person dies of acute coronary insufficiency (i.e., a sudden drop in blood supply to the heart triggered a fatal rhythm disturbance or pump failure), no necrosis will be found in the myocardium at autopsy. This generates much confusion among non-pathologists.

    But already it is time to depart, for me to die, for you to go on living; which of us takes the better course, is concealed from anyone except God.

        -- Socrates

    To die will be an awfully big adventure!

        -- Peter Pan (James Barrie)

    Let us so live that when we come to die even the undertaker will be sorry.

        -- Mark Twain

    I am going to the great Perhaps.

        -- Rabelais, last words

    Neil Gaiman's "Death"
    Character fan art


The boundaries that divide Life from Death are at best shadowy and vague. Who shall say where the one ends, and the other begins?

      -- Edgar Allen Poe, "The Premature Burial"

    LYSOSOMES: For some reason, "Big Robbins" reviews the basic cell biology of lysosomes here. It's common (especially in full-type phagocytes) to see a bacterium or bit of debris within a phagolysosome (HETEROPHAGOCYTOSIS). You may also see an organelle being digested within a phagolysosome (AUTOPHAGOCYTOSIS). A RESIDUAL BODY is a phagolysosome filled with already-digested debris, and in lysosomal storage diseases, they fill with metabolites that patients cannot break down.

      * Amiodarone, the heart rhythm drug, binds to phosopholipids in lysosomes and renders them insoluble.

      * Chloroquine raises the pH in lysosomes and renders their enzymes less active.

    PROLIFERATION OF SMOOTH ENDOPLASMIC RETICULUM: Overgrowth of the drug-metabolizing equipment of drug-exposed liver cells. (We prefer the term "proliferation" for this process, rather than "hypertrophy" or "hyperplasia".) We can tell by the cell's light microscopic appearance, but we won't ask you to do this.

    MITOCHONDRIAL ALTERATIONS are cited by "Big Robbins". Giant mitochondria are seen in alcoholic (and other) liver disease, odd mitochondria are hallmarks of certain muscle diseases, and occasionally weird ones are seen in cancer.

      More familiar is the process of "getting in shape" by physical conditioning. This process probably involves increasing the efficiency (though maybe not appearance, size, or numbers) of mitochondria in affected muscles. Leave this to the physiologists.

      Certain cells become literally stuffed with mitochondria. In health, these include the apocrine sweat glands of the armpits, and the "oxyphil" cells of the parathyroid glands. In disease, such cells are generically called HüRTHLE CELS or ONCOCYTES (the latter, which means "swollen cells", is a terribly confusing word.)

    CYTOSKELETON PROBLEMS are currently under much study. For your reference:

      MICROTUBULES... 20-25 nm (* the vinca drugs used for chemotherapy bind these, thus preventing mitosis from being completed)

      MYOSIN... 15 nm (in muscle) or 8 nm (non-muscle)


      ACTIN... 6- 8 nm (* experimentalists: prevent these from forming using cytochalasin B)

      CHEDIAK-HIGASHI SYNDROME is a genetic white cell disease in which microtubule protein fails to polymerize. This isn't the whole story, since the major problem that these people have is failure of lysosomes to fuse with phagocytic vacuoles.

      COLCHICINE disrupts microtubules, while CYTOCHALASIN B disrupts microfilaments.

      Defects in the DYNEIN ARMS OF THE MICROTUBULES within cilia cause infertility in both sexes, problems keeping the airways clean, and sometimes problems in getting the embryo's guts into the right places. More on these ("Kartagener's syndrome" and others) later.

      The intermediate filaments are supposed to keep organelles in their positions. They include KERATIN (for epithelium; there are several subtypes), NEUROFILAMENTS, GLIAL FILAMENTS, VIMENTIN (for mesenchyme), and DESMIN (for muscle). MALLORY'S HYALINE in the boozer's liver is scrambled prekeratin, while NEUROFIBRILLARY TANGLES in the brains of Alzheimer's patients and injured boxers are composed of tau protein, a microtubule-associated protein.

        * More than you ever wanted to know about the intermediate filaments, including mutations that cause some of the hereditary skin diseases collectively called EPIDERMOLYSIS BULLOSA: Science 25: 799, 1992; update Arch. Derm. 137: 1458, 2001.

      Even the cell membrane has its own underlying skeleton, including the protein SPECTRIN, which when deficient prevents the erythrocytes from assuming the forms of biconcave disks. (The patients have HEREDITARY SPHEROCYTOSIS, a fairly common disease. More about this later.)

DEVELOPMENTAL ABNORMALITIES: This covers a host of anatomic lesions in which "things grew wrong". This is a terminology section.

    CONGENITAL DISEASE can be shown to be present from birth. (Note that some genetic diseases do not announce themselves clinically until much later in life, and injuries to the unborn child can result in congenital, non-genetic disease.)

    APLASIA is the complete failure of an organ to form. (By a time-honored misuse, wipe-out of once-healthy bone marrow is called "aplastic anemia").

{15939} kidneys never formed ("renal aplasia / agenesis"; organ block of newborn child; the kidneys should be next to the small intestine)

    ATRESIA is the complete failure of the lumen, or a portion of the length of the lumen, to form where it should in a hollow organ..

    STENOSIS is a non-neoplastic narrowing of a lumen; it may be a birth defect, or acquired.

      Not birth defects, but you need to know: OCCLUSION is the complete obstruction of a lumen that was once open. SPASM is the narrowing or occlusion of a lumen due to inappropriate contraction of smooth muscle, or the inappropriate contraction of skeletal muscle anywhere.

    HYPOPLASIA is the failure of an organ to grow to normal size along with the rest of the body. (By another time-honored misuse, bone marrow with too-few cells is called "hypoplastic", even if it was once normal). "Atrophy" would be a better term.

{15632} hypoplasia of the nails (minor birth anomaly)

    LOCAL GIGANTISM is just as it sounds (the "Elephant Man", Nixon's masseters -- noted syndrome, see J. Oral. Max. Surg. 52: 1199, 1994 -- others that you know).

    MALFORMATION: Something was shaped wrong since the beginning.

    DEFORMATION: Something used to be well-formed, but its shape was permanently altered, other than by being cut apart.

      You are welcome to call both malformations and deformations "deformities".

    SYN- and HOLO- are prefixes that indicate failure to separate ("syndactyly" is fused fingers; "holoprosencephaly" is a brain without divided hemispheres). Failure to fuse has no special word root, but is also important ("hypospadias" is failure of a male's urethra to fuse; "harelip" you know).

    From a Saddam-era Iraqi
    propaganda website (!)

    SUPERNUMERARY ORGANS often recall those of other animals (very common are supernumerary nipples -- who's got one? -- and the less-visible accessory spleens), or might-have-beens in the history of life (polydactyly, i.e., six fingers on a hand, six toes on a foot).

Source unknown

    ECTOPIA / HETEROTOPIA is a well-formed bit of organ in the wrong place. If it's tiny and trivial, it's a HETEROPLASIA (for example, the common sebaceous glands on the buccal mucosa, called "Fordyce granules"). If it's big enough to interest a surgeon, it's called a CHORISTOMA.

      An organ that developed in the wrong place may be ECTOPIC (for example, a kidney in the pelvis); * you may hear the term "dystopia".

    HAMARTOMAS are the right components of an organ in the wrong arrangement. The best-known hamartomas are the vascular and pigmented birthmarks, and most "benign tumors of blood vessels" are really hamartomas.

      Like "real tumors", hamartomas can be clonal, indicating origin from a single mutated cell post-lyonization: Am. J. Path. 148: 1089, 1996. If you do not remember what lyonization is, this would be a good time to review.

      Unlike real tumors, most hamartomas grow along with the body at about the same rate. There's plenty waiting to be discovered.

{05756} cartilage hamartoma, lung (trust me; your lung is supposed to contain cartilage, in its bronchial walls, but not a cartilage golfball like this)
{28889} cartilage and cuboidal cell hamartoma, lung, microscopic view (the right components, i.e., cartilage and glands, but the wrong arrangement)
{49278} bile duct hamartomas, liver (trust me)
{49638} cardiac muscle hamartomas ("rhabdomyomas", trust me), tuberous sclerosis patient; identify the bumps without the normal heart muscle fiber pattern

    CYSTS are abnormal, closed, fluid-filled structures. Most definitions also stipulate that they be lined by epithelium (I'd consider those that don't to be wrong). Many (but by no means all) cysts are developmental defects, left over from embryogenesis.

      * In due time, you'll learn about "retention cysts" (resulting from plugged ducts), "implantation cysts" (after a bit of epidermis grows within the dermis following trauma), "hydatid cysts" (brood cavities for tapeworms), "hyperplastic cysts" (i.e., part of the common, banal "fibrocystic disease of the breasts"), cysts that form within tumors, "pseudocysts" (generally large cavities lined by partially-digested fat cells), and "cystic changes" resulting from liquefaction necrosis in brain, mesenchymal tumors, or elsewhere.

{25559} mucous cyst, within the lip
{25560} mucous cyst, being excised
{25569} cysts of the breast
{09652} synovial cyst, ankle; it has been cut and the thick, gooey fluid has poured out
{12504} epidermoid inclusion ("sebaceous") cyst, beneath skin
{16982} polycystic kidney (football-sized; more about this later)
{16983} polycystic kidney
{49336} cyst of the epididymis (the testis is the white structure)
{49396} mucinous cystadenoma of the ovary; this might have weighed 30 pounds or more
{49471} thyroglossal duct cyst
{49472} thyroglossal duct cyst, filled with jelly-like thyroglobulin

Vascular adrenal cysts
Pittsburgh Pathology Cases

    FISTULAS are abnormal openings between body surfaces. SINUSES, when not part of normal anatomy, are pathological openings from an abnormal fluid-containing cavity onto surfaces / an apparent fistula track to nowhere. If they're present for more than a very short time, each will epithelialize (of course, why?) Either may sometimes represent a developmental defect.

{49228} anal fistula

    A DIVERTCULUM is an outpouching of the entire wall of a tubular organ. This is most often a birth defect or the result of something pulling on the side of the tube for a long time.

    A PSEUDODIVERTICULUM is an outpouching of the mucosa through a weakness in the wall of a tubular organ. This is most often the result of too-high pressure for too long in the lumen.

ATROPHY: "Shrinkage in the size of the cell by loss of cell substance" ("Big Robbins"), without the cell actually dying. When many cells each become smaller, the organ itself become smaller. Defined this way, atrophy is very reversible.

From Chile
In Spanish

    Examples of real atrophy are:

      Wasting of skeletal muscle on disuse (casted extremity, couch potato, diaphragm of a patient on a ventilator NEJM 358: 1327, 2008); wasting of the myocardium of a bed-ridden patient or a weightless astronaut (1%/day, NEJM 358: 1370, 2008)

Atrophic muscle fibers.
Trichrome stain.
WebPath Photo

Atrophic liver cells.
From ischemia.
WebPath Photo

Hypertrophy and Atrophy

{14424} atrophy of type II fibers in a couch potato
{17445} atrophy of arm and chest muscles after nerve injury
{17446} atrophy of most muscle cells after nerve injury
{53704} atrophy of the left arm after a stroke
{14372} Werdnig-Hoffman disease of motor nerves; most muscle cells underwent atrophy

      Loss of innervation of skeletal muscle (polio, nerve damage, nerve disease)

        * The molecular biology, which of course involves inhibition of RNA transcription, is just now being worked out (Proc. Nat. Acad. Sci. 91: 3647, 1994).

      Diminished blood supply (various organs -- this includes "pressure atrophy") or inadequate nutrition (various organs).

      Loss of normal trophic stimulation, for example endocrine stimulation. This is very important; most organs that depend for their function on endocrine stimulation (adrenals, testes, a man's skeletal muscles) will diminish in size if the stimulating hormone is no longer available.

      * Chronic inflammation in the area -- maybe. Nobody knows why chronic gastritis ultimately causes atrophy of the mucosa.

{17447} atrophy of thyroid (left; right side is normal thyroid at much lower magnification)

      "Aging" is cited by "Big Robbins", though I am not impressed that geriatric cases have appreciably smaller cells when all other things are equal.

        As we'll see later, an older adult who stays fit (for example, Dennis Quaid, show here at age 53) can out-perform almost all of today's nintendo-playing teens in any test of physical fitness.

        As cells take part in atrophy, especially by loss of size, the extra proteins are disposed of using ubiquitin ligases and proteasomes as you'd expect. Organelles may be eaten in phagolysosomes ("autophagy").

        Cell loss is most of the story in the brain. Lower sex hormonal levels explain atrophy of tissues dependent on them -- here the cells truly get smaller, and in the breast may vanish. Bone loss and thinning of the dermis as we age aren't well understood -- again, cells are lost rather than shrink. The other organs simply don't atrophy in healthy old age.

        Purists use the term "involution" for decrease in cell or organ size as a result of the maturation/aging process (i.e., "the thymus undergoes involution later in childhood").

    Atrophic cells have fewer organelles and do not function as well as their normal counterparts. As cells atrophy, their lysosomes consume their organelles. Again, some of the debris is non-digestible and ends up as lipofuscin -- contributing to "brown atrophy".

      Especially when the cause of atrophy is inadequate blood supply or nutrition, the atrophic cells may go on to die and be replaced by scar tissue and/or fat. Probably in all the cases listed above except for skeletal muscle, there is loss of individual cells.

      * You may run into the term AUTOPHAGY for cells in distress eating their organelles for protein synthesis. We can now detect the involved molecules; not surprisingly, it's part of the downward cycle in congestive heart failure (Circ. 120(11-S): S-191, 2009). There is now talk about "autophagic cell death", in contrast to apoptosis and necrosis -- stay tuned to see if this becomes a standard term in pathology.

{10247} atrophy of a kidney supplied by a narrowed artery ("ischemic atrophy")
{25767} atrophy of a kidney supplied by a narrowed artery ("ischemic atrophy")
{17448} ischemic atrophy of renal tubules in a high blood pressure patient (left side)
{33047} ischemic atrophy of a cerebral hemisphere in chronic vascular disease
{34403} ischemic atrophy of a cerebral hemisphere in chronic vascular disease

    Looser usage allows the word "atrophy" to be used for widespread loss of cells (usually by apoptosis, if you catch them dying at all), without shrinkage of survivors. This misnomer has been hallowed by long tradition when applied to the brains of heavy drinkers, Alzheimer's disease, and the elderly.

{10847} brain "atrophy" (wide sulci, narrow gyri)
{34478} brain "atrophy" (wide sulci, narrow gyri)
{34481} brain "atrophy" (wide sulci, narrow gyri)
{49554} atrophy of the cerebral peduncle following a stroke involving the motor cortex

Brain atrophy.
"Alzheimer's" (Pick's?)
WebPath Photo

Superior vermal atrophy
Alcohol-induced brain lesion

{10898} "Testicular atrophy", gross, with a normal for comparison
{00086} "Testicular atrophy", adult man, no spermatogenesis whatsoever

Testicular atrophy.
Maybe mumps or old torsion.
WebPath Photo

{39457} bone marrow "atrophy"; only 20% of the marrow is hematopoietic cells (low even for old age), 80% is fat

{15426} atrophy of the gastric fundus mucosa in an elderly patient; smooth, shiny (i.e., thin epithelium), no rugae

HYPERTROPHY: Increase in the sizes of cells, and hence the size of the organ.

Hypertrophy and Hyperplasia
From Chile
In Spanish

{18668} "built up"; hypertrophied muscles
{18642} "built up"; hypertrophied muscles

{03347} cardiac hypertrophy (either side, normal in center; the giveaway is the giant nuclei)
{06380} cardiac hypertrophy (left), normal on right
{06383} cardiac hypertrophy (left), normal on right
{17454} cardiac hypertrophy (left), brown atrophy on right

Myocardial cell hypertrophy
Ed Lulo's Pathology Gallery

Athletic heart
Tom Demark's Site

Heart hypertrophy.
High blood pressure.
WebPath Photo

Heart hypertrophy
Urbana Atlas of Pathology

Heart hypertrophy
Urbana Atlas of Pathology

Hypertrophic heart
Tom Demark's Site

Myostatin-deficient cow
Muscle hypertrophy
Watch this one


    "An increase in the number of cells in a tissue or organ" -- Big Robbins.

    "When an organ grows by increasing the number of its cells" -- R&F. By definition, the cells appear normal. This may be physiologic ("Big Robbins" distinguishes "compensatory / growing back " and "hormonal / working overtime" -- in health, it's probably all mediated by molecules), or pathologic (i.e., the result of genetic mutations or environmental changes).

      A physician need only be concerned with whether the hyperplasia is a result of an overgrowth of mutated cells, which makes for a possible cancer risk.

      * Expect in the near future to find genetic injuries that drive "pathologic hyperplasias" that are so familiar in the prostate and endometrium.

Thyroid hyperplasia
in endemic goiter

{49360} idiopathic "hypertrophy" of one breast. Actually, this is probably the result of an embryonic mutation, hence best considered a neoplasm.

{09217} adrenal cortex ("stressed"; compare a normal, otherwise this is hard to appreciate)

{24694} testis with Leydig cell hyperplasia (the cells between the tubules with the abundant eosinophilic cytoplasm; this shows lots too many of them)

{49450} parathyroid gland hyperplasia (they're big, trust me)

{49376} endometrial hyperplasia (uterus has been opened anteriorly; the hyperplastic endometrium appears as a blob)

Prostate hyperplasia.
Old guy.
WebPath Photo

Prostate hyperplasia.
Old guy. Lots of infolded glands.
WebPath Photo

{10743} prostatic hyperplasia (paper clip demonstrates urethral stenosis)

{24827} sebaceous gland hyperplasia

{25557} hyperplasia of gingival tissue in a patient receiving phenytoin ("Dilantin") therapy (this is often misnamed "hypertrophy")

METAPLASIA: "(Adaptive) substitution of one type of adult or fully differentiated cell for another type of adult (or fully differentiated) cell" -- Baby Robbins. "A reversible change in which one adult cell type replaced by another adult cell type." -- Big Robbins. "Conversion of a differentiated cell type into another" -- R&F.

{15432} stomach mucosa with intestinal metaplasia (right; there's a bit of dysplasia/anaplasia as well); normal at left
{19347} stomach mucosa with intestinal metaplasia (goblet cells, etc.)

{19453} columnar metaplasia ("Barrett's" change) of esophageal mucosa (note the goblet cells)

DYSPLASIA ("atypia", "atypical hyperplasia", "pre-cancer", "intraepithelial lesion", etc.; word favored by Dr. Papanicolaou and losing favor lately): "Bad growth". This has always meant abnormal cell organization. By convention today, unless otherwise specified, this implies a very abnormal epithelium with "loss of uniformity of the individual cells, as well as a loss of their architectural orientation". This includes "atypical hyperplasia" and "atypical metaplasia" as well as the oxymoronic old term "intra-epithelial neoplasia".

HPV -- trust me.
WebPath Photo

Dysplasia, pap smear
Urbana Atlas of Pathology

WebPath Photo

WebPath Photo

Pap smear
WebPath Photo

Really bad dysplasia
(Carcinoma in situ)
WebPath Photo

Dysplasia in bronchial epithelium
Topsy-turvy cells

High-grade carcinoma
Dave Barber MD, KCUMB

Bladder carcinoma in situ
Very anaplastic, no invasion
KU Collection

{11490} dysplasia in the endocervix (upside-down; note N/C ratio, hyperchromatic cells, mitotic figures off the basement membrane)
{39605} dysplasia in the endocervix (note N/C ratio, failure of maturation)

{11484} dysplasia in a colon polyp (note N/C ratio, crowding, loss of mucin production)

{15441} dysplasia in gastric mucosa (note N/C ratio, cells lying topsy-turvy)

{25297} urothelial dysplasia / maybe even carcinoma in situ (note N/C ratio, very large and hyperchromatic nuclei, topsy-turvy arrangement)

{08911} carcinoma in situ of the endocervix, replacing epithelium and growing into a fold
{10079} carcinoma in situ of the bronchus
{11491} carcinoma in situ of the endocervix, replacing the columnar epithelium

LOOKING AT ORGANS: You learn by doing.



* PS: You'll learn "Death and the doctor" in other courses, i.e., how to break bad news, how to help families, what problems they will face caring for a dying relative, and so forth. Don't expect everybody to go through the classic five stages, especially where there is a living and decent religious faith. "Death education" isn't well done in most medical schools, at least the allopathic ones (Surgery 113: 163, 1993). Do yourself a favor and read a book by yourself over vacation.

If one person dies, it's a tragedy. If a million people die, it's a statistic.

Once the game is over, the king and the pawn go back into the same box.

O sons of men,
Lean death perches upon your shoulder
Looking down into your cup of wine,
Looking down on the breasts of your lady.
Your are caught in the web of the world
And the spider Nothing waits behind it.
Where are the men with towering hopes?
They have changed places with owls
Owls who lived in tombs
And now inhabit a palace.

Life, like a dome of many-colored glass
Stains the white radiance of eternity
Until death tramples it to fragments.

In America today, the practices of medicine and law have so interfered with the dying process that death has become a perversion of the natural process.

Nor dread nor hope attend
A dying animal;
A man awaits his end
Dreading and hoping all.

Socrates said, "O son of Hipponikos, the old proverb, 'Naught Without Labor' (chalepa ta kala), is applicable to learning. And nomenclature is no small part of learning."

Life is a comedy to those who think, a tragedy to those who feel.

Chi-Lu asked Confucius how the spirits of the dead and the gods should be served. Confucius said, "You are not even able to serve other living people. How can you serve the spirits?" "May I ask about death?" said Chu-Li. "You do not understand even life. How can you understand death?"

To live will be an awfully big adventure!

Death is before me today / like the recovery of a sick man / like going forth into a garden after sickness.
Death is before me today / like the odor of myrrh, / like sitting under a sail in a good wind.
Death is before me today / like the course of a stream; / like the return of a man from the war-galley to his house.
Death is before me today / like the home that a man longs to see,/ after years spent as a captive.

Get out! Get out! Last words are for fools who haven't said enough already!

Cancer autopsy
Ed Lulo's Pathology Gallery

Medical mnemonics
Fun site maintained by
cyberfriend Robert O'Connor

I am prosector

Dr. Evan Williamson,
then a medical student, dissects

{18601} skull, a familiar symbol of human mortality


A note for my osteopathic medical school students

Today's scientific pathology had its inception in 1859 with Virchow's work. For his time, Dr. Still's ideas about disease were reasonably enlightened. Today's oath of the osteopathic physician promises that physicians will work together in a spirit of "progressive cooperation", that they will "keep in mind always nature's laws", and that they will "further the application of basic biologic truths to the healing arts and to develop the principles of osteopathy which were first enunciated by Andrew Taylor Still."

This course will focus on understanding disease in light of nature's laws as they really are, i.e., the principles of rational inquiry, and the essentials of physics, chemistry, and basic biology. At the human level, your study of pathology will constantly correlate physical structure and the function of the human being at every level, just as Dr. Still tried to do in the late 1800's.

The oath also makes the promise that you will always "keep in mind... the body's inherent capacity for recovery." Most of pathology is the really study of this capacity. In this course, you will learn how and when the body tends to heal itself, and how it fights off infection and repairs wounds. You will always learn of situations in which the capacity to nourish and heal goes awry (atherosclerosis, hypertension, autoimmunity), situations in which some phase of the power to heal is lacking (hemophilia, immune deficiency), and situations in which the body does nothing to protect itself (prion disease, Huntington's disease). You will also learn how the body wears out (Alzheimer's disease), how damage accumulates and propagates itself (cancer), and how the body damages itself fighting invaders (suppuration, tuberculosis, rheumatic fever). You will come to understand when you can intervene with the expectation of curing, and when you can only palliate and help the person and family live with incurable illness.

Dr. Still believed that the principles of disease are relatively straightforward, and urged learners to use the hands-on approach. Your course features an abbreviated lecture series coupled to a whole-person oriented lab experience in which you will be continually active.

The osteopathic oath-taker also promises to "be ever vigilant in aiding the general welfare of the community." Since Virchow, pathologists have considered public health and the politics of disease to be part of our discipline. There may not be easy answers, but the content is important.

I would like to think that an osteopathic medical education offers a common-sense, humane, and rational basis for treating disease, not just a welter of scientific facts for doctor-technicians. This isn't just "pathology with an osteopathic spin". It is how I think the subject should be taught everywhere.


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