Vitamins and Nutrition USMLE Step 1 Practice Question
A 30-year-old vegetarian male presents with progressive paresthesias in his lower extremities and gait disturbance over 6 months. He has followed a strict meat-free diet for 15 years without supplementation. Vitals: BP 118/76, HR 88, RR 16, Temp 37°C, SpO2 98%. CBC reveals hypersegmented neutrophils and MCV 102 fL. Serum B12 is 185 pg/mL. Vibratory sense is diminished distally; reflexes remain intact. Which of the following urinary findings is most likely present?
Answer choices
- AHemoglobinuria
- BPropionic aciduria
- CCystinuria
- DArgininosuccinic aciduria
- EMethylmalonic aciduriaCorrect answer
- FMethylglycine excretion
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