Department of Dermatology, Shiga University of Medical Science, Otsu, Shiga, Japan.
J Dermatol. 2024 Nov;51(11):1519-1522. doi: 10.1111/1346-8138.17251. Epub 2024 Apr 25.
Schnitzler syndrome (SchS) is a rare autoinflammatory disease characterized by chronic urticarial rash and monoclonal immunoglobulin M (IgM) or IgG gammopathy. Viruses, including COVID-19, activate the innate immune system, therefore SchS, in which the innate immune system is improperly activated, is hypothesized to be exacerbated by viral infection. However, there were no reported SchS cases exacerbated by any viral infection. Here, we report a SchS case with an unusual IgA gammopathy manifested and exacerbated by COVID-19 infection. This report advocates the need for recognizing unusual cases of SchS with monoclonal IgA, and following up on paraprotein like IgA even when it is initially undetectable in cases with SchS symptoms. We also hypothesize that existing autoinflammatory diseases may be exacerbated by COVID-19 infection in the case of a combination of these diseases.
希氏综合征（SchS）是一种罕见的自身炎症性疾病，其特征为慢性荨麻疹样皮疹和单克隆免疫球蛋白 M（IgM）或 IgG 血症。病毒，包括 COVID-19，可激活先天免疫系统，因此推测先天免疫系统异常激活的 SchS 会因病毒感染而加重。然而，尚无任何病毒感染加重 SchS 的报道病例。在此，我们报告一例由 COVID-19 感染引起和加重的不常见 IgA 血症的 SchS 病例。本报告主张有必要认识到 SchS 中伴有单克隆 IgA 的不常见病例，并对 SchS 症状患者即使最初未检测到 IgA 类免疫球蛋白也要进行随访。我们还假设在这些疾病合并的情况下，现有的自身炎症性疾病可能会因 COVID-19 感染而加重。
