Kerion mimicking erosive pustular dermatosis in elderly patients.

Erosive pustular dermatosis of the scalp typically occurs in elderly patients; a diagnosis of fungal kerion infection in this patient population may seem unlikely. We present 3 elderly patients who developed pustular eruptions on the scalp that were suggestive of erosive pustular dermatosis. Culture and/or biopsy findings initially excluded kerion fungal infections. Later, cultures isolated Trichophyton species from 1 patient and Microsporum species from 2 patients, and the correct diagnosis of kerion was made. All patients were treated successfully with oral terbinafine hydrochloride. Fungal infection can be suspected in some elderly patients with erosive pustular dermatoses of the scalp. Repeated cultures and biopsies of hair-bearing skin, scale, and cut hair samples may be required to establish the correct diagnosis of kerion.