Can You Identify This Mildly Pruritic Lesion?

 A 10-year-old boy presents with a 10-day history of a worsening rash on his nose. The patient says that the area is slightly itchy and a little tender. He denies rash elsewhere on his body.

What are you looking at here?

A.  Impetigo.
B.  Candidiasis.
C.  Ringworm.
D.  Contact dermatitis.
E.  Acne.

(Answer on next page.)

Answer: C. Dermatophyte infection

The sudden onset and dramatic appearance of the eruption could be misleading. A potassium hydroxide evaluation confirmed the diagnosis of a dermatophyte infection, C.

The lesions of impetigo and candidiasis would be expected to have a more golden crust. The typical clinical appearance of contact dermatitis and a history that implicated a causative agent were absent here. Acne of only 10 days’ duration does not resemble this lesion.

This patient’s ringworm responded quickly to a 1-week course of oral antifungal antibiotics in combination with a topical antifungal cream.