Schnitzler Syndrome: a Review.

PURPOSE OF REVIEW: We focus on recent advances in diagnosis and therapeutic strategies, as well as on pathogenesis of Schnitzler syndrome.

RECENT FINDINGS: New diagnostic criteria were established, and their external validity was assessed in a retrospective cohort study. The cytokine interleukin-1 (IL-1) plays a crucial role in the pathogenesis of the Schnitzler syndrome, and this explains the spectacular efficiency of IL-1 blocking therapies. The Schnitzler syndrome is now considered as a late-onset acquired autoinflammatory syndrome in which the cytokine IL-1 plays a crucial role. IL-1 blocking therapies are efficient on the inflammation-linked symptoms but not on the monoclonal component. Therefore, they probably don't reduce the risk of the development of lymphoproliferative disorders that remains the main prognostic issue. The link between autoinflammation and the monoclonal component needs to be further elucidated.