Microscopic examination of a hematoxylin-eosin–stained biopsy specimen from the right ear showed a dense neutrophilic infiltrate surrounding and infiltrating eccrine units, with necrosis of the secretory epithelium. There was extension into the deep reticular dermis. Special stains for bacterial and fungal organisms were negative. Intravenous methylprednisolone therapy (40 mg/d) was initiated, resulting in prompt improvement of the patient's symptoms. Three days later, the corticosteroid therapy was discontinued, and the patient immediately experienced a flare in symptoms. However, the medical team did not reinstate the therapy because of concerns about the patient's severely pancytopenic status. The condition subsequently cleared over the following 3-week period.