How would you treat this itchy scalp rash?

An 8-year-old boy has been complaining for the past month of an itchy rash on the right side of his scalp. The child has no lesions elsewhere and takes no medication.

What is your clinical impression?

A. Seborrheic dermatitis.

B. Seborrheic folliculitis.

C. Dandruff.

D. Tinea capitis.

E. Psoriasis.

Answer: Tinea capitis

The potassium hydroxide evaluation was positive for a dermatophyte, confirming the diagnosis of tinea capitis, D. Dandruff is not associated with erythema; psoriasis and seborrhea feature more diffuse involvement. Unlike a seborrheic dermatitis, this eruption is a discrete pattern that has lasted for 1 month.

Tinea capitis responds best to systemic antifungal therapy.