Vitamins and Nutrition USMLE Step 1 Practice Question
A 26-year-old pregnant female presents with persistent, dry, ulcerated skin over her knees and elbows for 8 weeks. Vital signs: BP 118/76, HR 88, RR 16, Temp 37°C, SpO2 98%. Examination reveals small, gray plaques on the conjunctiva bilaterally. She denies diarrhea or other GI symptoms. Recent serum retinol level is 28 μg/dL (normal >30). She takes prenatal vitamins without vitamin A supplementation. Which vitamin deficiency best explains her clinical findings?
Answer choices
- AExcessive cholecalciferol intake
- BThiamine deficiency
- CRetinol deficiencyCorrect answer
- DExcessive α-tocopherol intake
- EAscorbic acid deficiency
- FPyridoxine deficiency
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