Drugs and Diseases: 1C metabolism Flashcards
what in raw eggs binds biotin and can lead to deficiency?
avidin
what do seizures, hypotonia, ataxia indicate?
biotinidase/biotin deficiency
what do encephalopathic crisis, hair loss indicate?
holocarboxylase synthetase deficiency
what can cause folic acid deficiency?
- alcoholism
2. malabsorption disorders
what is the function of antifolate drugs?
stop cell division of rapidly dividing tumor cells
two examples of antifolate drugs and action?
- MTX (methotrexate) - inhibits DHFR
2. 5-fluorouracil - inhibits thymidylate synthase
how can you measure absorption of B12?
shilling test w/ radioactive B12
4 things that can cause B12 deficiency?
- vegan diet
- pernicious anemia (no GIF - old people)
- Crohn’s (intestinal malabsorption)
- achlorhydria (HCl needed to cleave B12 from protein)
symptoms of B12 deficiency
- megaloblastic anemia
- neuro: numbness, tingling, vertigo
- high methylmalonyl coA
how can you differentiate b/w folate and B12 deficiency?
neuro symptoms not seen in folate deficiency
causes of elevated homocysteine? (3 things)
- Methionine synthase defect (folate deficiency)
- methylene-THF reductase defect (B12 deficiency)
- mutant cystathione B synthase (homocystinuria)
what is homocystinuria and what are symptoms?
extreme hyperhomocystinemia
- eye lens dislocation
- Marfan-like symptoms
what is megaloblastic anemia?
- no DNA synthesis, but still have RNA synthesis
- RBC’s abnormally large and irregularly shaped
- high hypersegmented neutrophils in peripheral blood
what two deficiencies can cause megaloblastic anemia?
folate and B12
symptoms of folate deficiency?
- megaloblastic anemia
- impaired DNA replication
