Vitamins and Nutrition USMLE Step 1 Practice Question
A 41-year-old man on isoniazid and rifampin for pulmonary tuberculosis presents with irritability, progressive numbness in his hands, and new-onset generalized seizures. Vital signs: BP 128/82 mmHg, HR 92/min, RR 16/min, Temp 37.2°C. Peripheral blood smear reveals microcytic anemia with ring sideroblasts. Serum glucose is normal. He denies alcohol use. Which vitamin deficiency best explains his neurologic and hematologic findings?
Answer choices
- AFolate
- BBiotin
- CAscorbic acid
- DNiacin
- EPyridoxal phosphateCorrect answer
- FCyanocobalamin
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