Vitamins and Nutrition USMLE Step 1 Practice Question
A 50-year-old male with a 20-year history of alcohol use disorder presents with confusion, ophthalmoplegia affecting lateral gaze, and ataxia. Vital signs show BP 128/76 mmHg, HR 92 bpm, RR 16/min, temperature 37.2°C, and SpO2 98% on room air. MRI demonstrates mammillary body atrophy. Serum thiamine level is low at 2.5 ng/mL (normal >5.5). He denies recent seizures. Which enzyme requires the deficient vitamin as a cofactor?
Answer choices
- AAspartate aminotransferase
- BPyruvate carboxylase
- CMethylmalonyl-CoA mutase
- DProlyl hydroxylase
- EPyruvate dehydrogenaseCorrect answer
- FAlpha-ketoglutarate dehydrogenase
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