Metabolism USMLE Step 1 Practice Question
A 9 month old boy is evaluated for vomiting, diaphoresis, and lethargy that occur shortly after fruit puree is introduced into his diet. His parents report that he was previously well while exclusively breastfed. Examination shows hepatomegaly. Laboratory studies reveal hypoglycemia, elevated AST and ALT, and low serum phosphate. Which of the following is the most likely diagnosis?
Answer choices
- AEssential fructosuria
- BClassic galactosemia
- CMedium chain acyl CoA dehydrogenase deficiency
- DHereditary fructose intoleranceCorrect answer
- EPyruvate dehydrogenase deficiency
- FFructose-1,6-bisphosphatase deficiency
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