IL-1 blockade in Schnitzler syndrome: Ex vivo findings correlate with clinical remission

Schnitzler syndrome is defined as a combination of chronic urticaria, IgM gammopathy, and at least 2 of the following criteria: recurrent fever, arthralgia or arthritis, bone pain, lymphadenopathy, hepatomegaly or splenomegaly, leukocytosis, an elevated erythrocyte sedimentation rate, and abnormalities in bone morphology.1,2 As in the present case, there is usually a diagnostic delay of years. Long-term follow-up is warranted because some patients progress to Waldenström macroglobulinemia.1 Schnitzler syndrome is of unknown etiology; biopsy of skin lesions is generally in keeping with neutrophilic urticaria.3 The clinical response of patients with cryopyrinopathies such as MWS led to the use of anakinra in Schnitzler syndrome.4,5 To date, anakinra has resulted in complete remission of symptoms in all patients with Schnitzler syndrome; it does not seem to affect the IgM gammopathy.1 Most patients require daily dosing to prevent recurrence of symptoms, although intermittent dosing has sufficed in isolated cases.