Repeated USMLE Questions Step 1- 286

A 52-year-old alcoholic man complains of painful lesions on his tongue and inside his mouth. He also has hyper-pigmented scales on his face and both hands. He is weak, forgetful and suffers of burning sensation in several parts of his body. He mentions that he has diarrhea for the last two months.

Deficiency of which of these vitamins is responsible for this patient’s condition?

A-Vitamin A

B-Vitamin B3 (niacin)

C-Vitamin C

D-Vitamin D

E-Folic acid


This is a typical presentation of pellagra, niacin deficiency. The three Ds, Dermatitis, Dementia and Diarrhea are characteristic of this condition. Vitamin A deficiency is manifested by night blindness. Vitamin C deficiency or scurvy affects collagen synthesis through defective hydroxylation of proline and lysine amino acids. Defective collagen is responsible for delayed wound healing and abnormal bleeding. Scurvy lacks the 3 Ds which define pellagra. Vitamin D deficiency occurs in children as rickets and in adults as osteomalacia. It affects bone development and growth. Folic acid deficiency causes fatigue, loss of appetite, weight loss, headache and anemia. Deficiency of folic acid in pregnant women leads to neural tube defects in the fetus. Routine folic acid administration is recommended for all pregnant women. It doesn’t have the 3 Ds of niacin deficiency.

The correct answer is B

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