Diaminodiphenyl Sulfone-Induced Hemolytic Anemia and Alopecia in a Case of Linear IgA Bullous Dermatosis

Linear immunoglobulin A (IgA) bullous dermatosis (LABD) is an autoimmune mucocutaneous disease characterized by subepidermal blistering induced by IgA autoantibodies against several autoantigens in the basal membranous zone of the skin and mucosal tissue. Although diaminodiphenyl sulfone (DDS), also known as dapsone, is generally recognized as the first-line therapy for LABD, DDS can induce several severe side effects. We present a Japanese case of LABD with DDS-induced hemolytic anemia and alopecia. In the present case, the DDS-induced hemolytic anemia and hair loss made the DDS monotherapy difficult. When DDS is used in LABD patients with iron deficiency anemia (IDA), hemolytic anemia is concealed by IDA. It is thus necessary to carefully and frequently examine the laboratory data to find the signs of DDS-induced hemolytic anemia. Even though there is no literature on DDS-induced alopecia, alopecia was reported as one of the side effects of DDS in an FDA report, and, in our case, hair loss was improved after reducing its dosage. We have to recognize that alopecia is one of the side effects of DDS and that careful management is needed in order not to overlook the adverse side effects of DDS when treating LABD patients.