Metabolism USMLE Step 1 Practice Question
A 23 year old man develops jaundice and dark urine 2 days after starting trimethoprim sulfamethoxazole for a skin infection. He had a similar episode after eating fava beans. Laboratory studies show anemia, elevated indirect bilirubin, and elevated lactate dehydrogenase. Peripheral smear shows bite cells. Which of the following enzyme deficiencies is the most likely cause?
Answer choices
- AHexokinase
- BPyruvate kinase
- CGlucose 6 phosphate dehydrogenaseCorrect answer
- DAcid alpha glucosidase
- ESpectrin
- FGlutathione reductase
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