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Flashcards in vitamins 1 Deck (18):

What are the fat soluable vitamins? When would you see deficiencies?

ADEK. see difficiencies in malabsorption syndromes (steatorrhea), like Celiac's or mineral oil intake)


Which water soluable vitamins don't wash out of the body easily?

B12 and B9 (aka folate, which is stored in the liver)


What are common results of B complex deficiencies?

dematitis, glossitis, and diarrhea


Function of vitamin A

antioxidant. constituant of visual pigments (retinal). also important for normal differentiation of epithelial cells into specialized tissue (like pancreatic cells, mucus secreting cells). prevents squamous metaplasia.


What is vitamin A used to treat?

measles, AML, subtype M3 (15;17 translocation), isotretinoin is prescribed for severe acne.


What is seen in vitamin A deficiency?

night blindness (nyctalopia), dry, scaly skin (xerosis cutis) alopecia, corneal degeneration (keratomalacia), immune suppression


What is seen in vitamin A excess?

arthalgias, skin changes (scaly), alopecia, cerebral edema, pseudotumor cerebri, osteoporosis, hepatic abnormalities. teratogenic (cleft palate and cardiac abnormalities)- negative pregnancytest before you give isotretinoin for acne


Function of vitamin B1

aka thiamine.
in thiamine pyrophostphate (TPP). TPP is needed for several dehydrogenase reactions, including pyruvate dehydrogenas (links glycolysis to TCA), alpha-ketoglutarate dehydrogenase (TCA cycle), transketolase (HMP shunt), branched chain ketoacid dehydrogenase
(think ATP: alpha ketoglutarate dehydrogenase, transketolase, and pyruvate dehydrogenase


What is seen in B1 deficiency? Causes of B1 deficiency.

impaired glucose breakdown. ATP depeltion is worsened by glucose infusion and highly aerobic tissues like the brain and the heart are hurt first. causes WErnicke-Korsakoff and beriberi. seen in alcoholics and malnourished


How do you diagnose B1 deficiency?

increased RBC transketolase activity following B1 administration


Wernicke-Korsakoff syndrome

confusion, ataxia, opthalmoplegia (classic triad), plus confabulation, personality change, and memory loss. damage to medial dorsal nucleus of the thalamus and mamillary bodies. due to thiamine (B1) deficiency



B1 (thiamine) deficiency)
dry beriberi causes polyneuritis, symmetrical muscle wasting. wet beriberi causes high output cardiac failure and edema


Vitamin B2 function

aka riboflavin. component of flavins FAD and FMN, used as cofactors in redox rxns (ex. succinate dehydrogenase of TCA). (FAD and FMN are from riboFlavin)


Vitamin B2 deficiency

cheilosis (inflammation of lips, scaling and fissures at the corner of the mouth, corneal vascularization. (2 Cs of B2)


Vitamin B3 function

aka niacin. constituent of NAD and NADP. used in redox rxns. derived from tryptophan. synthesis requires B2 and B6. (NAD from Niacin)


How is B3 used medically

for tx of dyslipidemia. lowers levels of VLDL and raises HDL


What is seen in B3 deficiency. Causes.

glossitis. severe deficiency leads to pellagra. pellagra causes diarrhea, dementia/hallucinations, and dermatitis (Casal necklace and hyperpigmentation of sun-exposed skin). may be caused by Hartnup disease (AR metabolic disease that causes decr. tryptophan absorption), malignant carinoid syndrome (excess tryptophan metab), and isoniazid (decr. vitamin B6).
connection to tryptophan is that tryptophan can be converted to niacin.


What is seen in B3 excess

facial flushing induced by porstaglandin (not histamine), hyperglycemia, hyperuricemia