Nutritional Disease study notes Protein-energy malnutrition - kwashiorkor - often follows the birth of a younger sibling, which displaces the baby from the breast - low serum albumin - almost no peroxisomes in their liver - children are edematous, dull, and apathetic - look for depigmentation of skin and hair - eventually, a vicious cycle of between protein deprivation and loss of the villi, microvilli, and disaccharides of the gut - marasmus - patients exhibit emaciation, monkey faces, extreme growth failure, and extreme hunger - tend to be exacerbated by infections Vitamins - fat-soluble vitamins - A, D, E, K - water-soluble vitamins - B, C, folic acid - vitamin A - exists as retinol, retinal, retinoic acid - stores in liver and shuttles it around on transthyretin - responsible for maintaining the differentiation of certain special kinds of epithelium, and in the deficiency state, epithelial surfaces of all kinds tend to undergo squamous metaplasia and hyperkeratinize - xeropthalmia, Bitot's spots, keratomalacia, and ultimately blindness - other problems are kidney stones, acne, lung infections, and immunodeficiency - precursor of visual pigments - excess vitamin A intake produces increased intracranial pressure, with headache and nausea vomiting; some vitamin A molecules are teratogens - vit A overdose may cause skin discolorization - vitamin D - deficiency is rare in U.S. - problem among the dark-skinned people or at very high altitudes - usual causes of vit D deficiency include malabsorption, nephrotic syndrome, antacid buffs - bony lesions of vit D deficiency are called ricketts in growing children, and osteomalacia in adults - essential lesion is failure of osteoid to mineralize - in ricketts, the epiphyseal cartilage does not calcify - in osteomalacia, the non-calcified bone looks pale on x-ray, and tends to break - vegetarian eating style can cause osteomalacia - vitamin E - patients have malabsorption, and suffer pigmentation and dysfunction of the gut and sensory pathways of the spinal cord - used to cure hemolytic anemia of preemies - CF babies are prone to vitamin E deficiency and get the same kind of hemolytic anemia - vitamin K - the co-factor for the synthesis of gamma-carboxyl glutamic acid, which is required for the calcium binding clotting factors II, VII, IX, and X, plus protein C, S, and Z - deficinecy is mostly seen in newborns and in those with lipid malabsorption - little in milk - functional vit K deficiencies are seen with those on coumarin - vit K is given to preemies, newborns, and people in liver failure in the hopes of preventing serious hemorrhages - vitamin B1 (thiamine) - the cofactor for burning alpha-keto-acids, and for transketolase - also maintains nerves - deficiency produces - a cardiomyopathy, plus generalized dilatation of arterioles requiring high output - a peripheral neuropathy - Wernicke-Korsakoff's syndrome - vitamin B2 (riboflavin) - precursor for the cofactor FAD - effects alcoholics and malnourished - cheliosis, seborrheic -type dermatitis of the nose, cheeks, hands, and purple tongue - vitamin B3 (niacin) - precursor for the cofactor NAD - can make it from tryptophan - if you see pellagra, it is probably in an alcoholic or a food faddist - rare causes include carcinoid syndrome, in which tryptophan is preempted to make serotonin, and Hartnup disease, in which patients cannot absorb tryptophan from the gut - niacin deficiency produces the three D's - dermatitis - diarrhea - dementia - vitamin B6 (pyridoxine) - cofactor that is responsible for shuttling amino groups and amino acids around - deficiencies occur in alcoholics, and pregnant lactating women - functional deficiencies in people taking isoniazid, penicillamine - minor neurological and mouth problems - folic acid - cofactor that helps shuttle methyl groups through pathways - best source is uncokked vegetables - clinical picture is metablastic anemia - common in alcoholics, pregnant women, people with malabsorption, and people taking phenytoin, and the mentally ill - vitamin B12 (cobalamin) - other cofactor for handling methyl groups - deficiencies in vegetarians - or those with pernicious anemia, tapeworm, blind loop syndrome, and inflammation of the terminal ileum - biotin - avidin in raw eggs is very effective at blocking absorption of biotin - vitamin C (ascorbic acid) - humans cannot synthesize this redox cofactor, which is involved in developing and maintaining collagen, synthesizing chondroitin sulfate, as well as a variety of other important things - deficiency is scurvy - related to osteoid synthesis and collagen support of the blood vessels - in children, the osteoblasts lay down scanty, poor-quality osteoid (similar to ricketts) - the cappillaries weaken - patients bruise easily, and bleed spontaneously - a secondary functional folic acid deficiency develops, because vit C is responsible for maintaining folate in its reduced state Minerals - iron - absorbed by duodenum, which regulates the total body load - most common deficiency - menstrating women and inadequate diets; blood loss, people eating iron-binding substances - one Georgia teen in three is iron deficient - deficiency is a microlytic, hypochromic anemia - can get good measure on stores by serum ferritin - also look for zinc protoporphyrin levels in blood - easily treated - zinc - deficiency in patients with malabsorption - distinctive feature is acrodermatitis enteropathica - copper deficiency - in preemies and in starvation - best-known disease in Menke's kinky hair disease - required to maintain proper oxidation states of iron, patients become anemic - required for cross-linking lysine side chains in collagen, these people get bony abnormalities - required to oxidize melanin to the dark form, depigmentation occurs - selenium deficiency - cause of China's endemic Keshan disease - a heart failure syndrome - miliary patches of hyaline necrosis through the heart muscle - sometimes seen in long-term hyperalimentation patients - magnesium deficiency - ultra-rare - remember that manganese poisoning simulates Parkinsonism Obesity - determined by heredity and especially steroid hormones - problems fat causes - muskuloskeletal problems - contributes to high blood pressure - lots of fat contributes to insulin release - contributes to gallstones - delays healing - enhances activation of estrogens (uterine cancer) - raises serum uric acid levels (gout) - lowers LDL cholesterol Hunger - in alcoholism, first look for folate and thiamine deficiency and protein-calorie malnutrition - convincing link between low-roughage diet and colon cancer - high animal-fat diet was never plausibly linked to breast cancer, and the idea now seems to be discredited - a group in Hawaii looked at lung cancer and found no correltaion whatever in the diet - the epidemic Chinese throat cancer has been tentatively linked to ingestion of a fungus-rich, pickled salt-fish ethnic delicacy - bad diet conspires with hepatitis B infection to produce liver cancer in poorer nations - women with low levels of vitamin A are indeed at greater risk for breast cancer; there's no apparent benefit from extra vit A in preventing breast cancer; no relationship between breast cancer and vitamin C could be found