The Development or Exacerbation of an Autoimmune Disorder Associated with SARS-CoV-2 infection: a Systematic Review of Case Reports

Abstract Background: Infections have long been studied as environmental triggers of autoimmunity. Previous associations between coronavirus and autoimmune disorders make severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus identified in December 2019, a potential candidate for autoimmune disorder development. Indeed, an increasing number of these cases have been reported prompting a characterization and summarization of existing evidence.Objectives: This review aims to characterize and summarize case reports documenting the development or exacerbation of an autoimmune disorders associated with SARS-CoV-2 infection.Methods: A bibliographic search of Embase was performed from inception to July 2020. Studies included reported the development or exacerbation of an autoimmune disorder associated with SARS-CoV-2 infection. Quality was judge using Joanna Briggs Institute Critical Appraisal Checklist for Case Reports and piloted forms were used for data collection. Data were summarized using descriptive statistics and narrative synthesis.Results: From 304 entries, 85 different cases were included, 41%-99% with good appraisal across quality domains. Sixty-two (72.9%) patients had no previous autoimmune disorder and 70 (82.4%) developed it De novo, the most frequent being Guillain–Barré syndrome and multisystem inflammatory syndrome in children. Eighteen (21.2%) cases of autoimmune disorders, mostly in remission, exacerbated. Organ-specific disease was found in 57 (67.1%) and systemic in 28. Disease affection was categorized into groups, the most frequent being neurological (36; 42.4%), vasculitis (19; 22.4%), blood (15; 17.6%), and connectivitis/systemic lupus erythematosus/antiphospholipid syndrome (6; 7.1%). The median coronavirus disease-2019 to De novo autoimmune disorder latency was 11 days (IQR = 5.75-16).Conclusions: Although, as a systematic review of case reports, this study cannot verify causality, it provides support for further studies on the relationship between SARS-CoV-2 and autoimmune disorders. Furthermore, it delivers a characterization and summarization of existing reports making it a resource for clinicians to be aware of possible autoimmune disorder complications while taking care of their SARS-CoV-2 infected patients.