Chronic urticaria and monoclonal IgM gammopathy (Schnitzler syndrome): report of 11 cases treated with pefloxacin.

BACKGROUND Schnitzler syndrome is characterized by chronic urticarial rash and monoclonal IgM gammopathy and is sometimes associated with periodic fever, arthralgias, and bone pain. Current treatment is unsatisfactory. OBSERVATIONS Eleven patients with Schnitzler syndrome were treated with oral pefloxacin mesylate (800 mg/d). In 10 patients, we observed a dramatic and sustained improvement of urticarial and systemic manifestations. Corticosteroid therapy could be stopped or reduced in 6 patients. In 9 patients, pefloxacin was administered for more than 6 months (<or= 10 years), with a good safety profile. CONCLUSIONS Pefloxacin therapy can be considered for patients with Schnitzler syndrome because it usually improves chronic urticaria and the systemic symptoms of the disease.