Vitamins and Nutrition USMLE Step 1 Practice Question
A 62 year old woman presents with progressive numbness in her feet and difficulty with balance. She underwent ileal resection several years ago for Crohn disease. Laboratory studies show hemoglobin 9.4 g per dL, mean corpuscular volume 112 fL, elevated homocysteine, and elevated methylmalonic acid. Which of the following deficiencies best explains her neurologic findings?
Answer choices
- ACopper deficiency
- BFolate deficiency
- CVitamin B12 deficiencyCorrect answer
- DIron deficiency
- ENiacin deficiency
- FVitamin B6 deficiency
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