Cerebrovascular Disease USMLE Step 1 Practice Question
A 10-year-old boy with cystic fibrosis presents with progressive gait instability and loss of vibration sense in the lower extremities. Vital signs are stable (BP 110/68, HR 88, RR 20, Temp 37°C, SpO2 98% on room air). Laboratory studies reveal hemoglobin 10.2 g/dL with normal MCV and reticulocyte count of 2.8%. Peripheral blood smear shows schistocytes. He denies recent infections. Which nutrient deficiency best explains these neurologic and hematologic findings?
Answer choices
- AVitamin B6
- BVitamin B12
- CFolate
- DVitamin B1
- EVitamin ECorrect answer
- FVitamin K
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