Angular cheilitis (perleche) is most commonly associated with a deficiency of which vitamin?

Correct answer: A. Vitamin B2 (riboflavin)

• A. CORRECT — Vitamin B2 (riboflavin) deficiency is the classic cause of angular cheilitis (fissured, erythematous corners of the mouth). Other nutritional deficiencies (iron, B3) and Candida infection also contribute, but riboflavin deficiency is the classic textbook answer.
• B. INCORRECT — Vitamin C deficiency causes scurvy (bleeding gums, perifollicular hemorrhages), not angular cheilitis.
• C. INCORRECT — Vitamin A deficiency causes night blindness, xerophthalmia, and skin changes — not angular cheilitis.
• D. INCORRECT — Vitamin B12 deficiency causes glossitis, burning tongue, and macrocytic anemia, but angular cheilitis is more specifically linked to riboflavin deficiency.