A 30-year-old male presents with pruritic, erythematous papules on the extensor surfaces of the elbows and knees
Question : A 30-year-old male presents with pruritic, erythematous papules on the extensor surfaces of the elbows and knees, accompanied by silvery-white scales. What is the most likely diagnosis?
A. Atopic dermatitis
B. Psoriasis (psoriasis vulgaris)
C. Eczema
D. Seborrheic dermatitis
Answer: B
Explanation: The typical manifestations of psoriasis vulgaris include well-defined erythematous papules or plaques with silvery-white scales, often distributed on the extensor surfaces of the elbows, knees, scalp, etc., and pruritus may occur. Atopic dermatitis is more common in flexor folds with dry skin; eczema has exudative manifestations in the acute phase; seborrheic dermatitis is mainly distributed in seborrheic areas (scalp, nasolabial fold) with yellowish scales. Therefore, the correct answer is B.
