Abstract：
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.
摘要：
Schnitzler综合征（SchS）是一种罕见的自身炎症性疾病，其特征是慢性荨麻疹皮疹和单克隆免疫球蛋白M（IgM）或IgG丙种球蛋白病。病毒,包括COVID-19，激活先天免疫系统，因此SchS,先天免疫系统被不正确激活，据推测病毒感染会加剧。然而,没有报告任何病毒感染加重的SchS病例.这里,我们报告了一例因COVID-19感染而表现并加剧的异常IgA丙种球蛋白病的SchS病例。本报告主张需要识别带有单克隆IgA的SchS的异常病例，并跟进类似IgA的副蛋白，即使在有SchS症状的病例中最初检测不到。我们还假设，在这些疾病的组合情况下，COVID-19感染可能会加剧现有的自身炎性疾病。
