Vitamins and Nutrition USMLE Step 1 Practice Question
A 9-year-old boy presents with progressive gait instability and decreased vibratory sensation in lower extremities. He has chronic steatorrhea and failure to thrive. Vital signs show BP 95/60, HR 88, RR 18, temp 37°C. Peripheral blood smear reveals acanthocytes. Serum cholesterol is markedly decreased at 95 mg/dL. He denies vision problems. He has never taken fat-soluble vitamin supplements. Deficiency of which vitamin most likely explains his neurologic and hematologic findings?
Answer choices
- AVitamin K
- BVitamin B1
- CVitamin D
- DVitamin A
- EVitamin ECorrect answer
- FVitamin B12
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