부산대학교 도서관

A question arises as to whether iSALT formation is a common cutaneous feature of Schnitzler syndrome or a unique phenomenon seen only in our patient, who manifested wheals on recurrent erythematous patches. Inducible skin-associated lymphoid tissue (iSALT) in a patient with Schnitzler syndrome who manifested wheals on recurrent localized erythema Dear Editor, Schnitzler syndrome is characterized by a chronic urticarial rash with an intermittent fever, and is considered to be an acquired form of autoinflammatory syndrome because its clinical phenotypes are similar to cryopyrin-associated periodic syndrome with a gain-of-function mutation in I NLRP3 i .1 Patients with Schnitzler syndrome also exhibit IgM monoclonal gammopathy, and 15-20% of patients eventually develop a lymphoproliferative disorder resembling Waldenström macroglobulinaemia with an I MYD88 i mutation.2 At present, the precise pathogenesis of Schnitzler syndrome remains unknown.3 Chronic inflammation in the skin triggers the development of tertiary lymphoid structures, and in a mouse model, we proposed the term of inducible skin-associated lymphoid tissue (iSALT) that efficiently activates effector T cells.4 Subsequently, we showed that some inflammatory skin diseases in humans can also form iSALT structures, i.e. formation of the central B-cell zone in lymphoid follicles, lined with the expression of the B-cell chemoattractant CXCL13, while in the surrounding T-cell zone, peripheral lymph node addressin (PNAd)-positive vessels indicating differentiation towards high endothelial venules (HEVs) were observed.5,6 Here, we describe a case of Schnitzler syndrome that exhibited iSALT with a peripheral distribution of IgM-expressing plasma cells. [Extracted from the article]