Anemias USMLE Step 1 Practice Question
A 6 year old boy is brought for abdominal pain, constipation, and declining school performance. His family recently moved into an older home undergoing renovation. Physical examination shows a bluish gingival line. Laboratory studies reveal microcytic anemia. Peripheral smear demonstrates basophilic stippling. Which of the following enzymes is most likely inhibited in this patient?
Answer choices
- AFerrochelatase and delta aminolevulinic acid dehydrataseCorrect answer
- BPyruvate kinase
- CGlucose 6 phosphate dehydrogenase
- DAdenosine deaminase
- EDihydrofolate reductase
- FCytochrome c oxidase and NADH dehydrogenase
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