An unusual presentation of immunodeficiency with hyper-IgM.

Hyper-IgM syndrome is a rare immunodeficiency disease characterized by markedly decreased serum IgG, IgA, and IgE levels but normal or elevated IgM levels. The most common clinical signs are infections, cirrhosis, arthritis, malignancies, and mucosal ulcers. Approximately two-thirds of patients have chronic neutropenia associated with oral and perirectal ulcers. We report a 14-month-old girl with hyper-IgM syndrome who has recurrent cutaneous ulcers restricted to the diaper area.