Schnitzler Syndrome Without a Monoclonal Gammopathy

Abstract

Background: Schnitzler syndrome (SS) is a rare autoinflammatory disorder characterized by a recurrent urticarial rash and a monoclonal immunoglobulin M gammopathy, as well as 2 of the following minor criteria: recurrent fever (>38°C), objective signs of abnormal bone remodeling, elevated C-reactive protein level or leukocytosis, and a neutrophilic infiltrate on skin biopsy. Alternatively, a monoclonal immunoglobulin G gammopathy may be present along with 3 minor criteria for diagnosis. Objective: To report a rare case of SS without monoclonal gammopathy and inform physicians of this possible clinical presentation so that treatment is not delayed. Methods: We report a case of a 62-year-old white man with a clinical diagnosis of SS without monoclonal gammopathy. He presented with chronic urticaria unresponsive to conventional therapy. Results and Conclusions: To our knowledge, there have only been 3 case reports of SS in the absence of monoclonal gammopathy documented in the literature. SS should be considered based on clinical presentation, even in the absence of monoclonal gammopathy, to facilitate appropriate management.