Metabolism USMLE Step 1 Practice Question
A 2 month old boy has poor feeding, tachypnea, and developmental delay. He has intermittent ataxia and hypotonia. Laboratory studies show elevated serum lactate and pyruvate, but his lactate to pyruvate ratio is normal. Brain MRI demonstrates ventriculomegaly and corpus callosum abnormalities. Which of the following is the most likely enzyme deficiency?
Answer choices
- AFructokinase
- BPyruvate carboxylase
- CGlucose 6 phosphatase
- DPyruvate dehydrogenase complexCorrect answer
- EPropionyl CoA carboxylase
- FCytochrome c oxidase
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