COVID-19 and autoimmune diseases

Abstract

Purpose of review: The aim of this study was to evaluate the relationship between infection with SARS-CoV-2 and autoimmunity.

Recent findings: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome (SARS) associated coronavirus 2 (SARS-CoV-2). Although most of the infected individuals are asymptomatic, a proportion of patients with COVID-19 develop severe disease with multiple organ injuries. Evidence suggests that some medications used to treat autoimmune rheumatologic diseases might have therapeutic effect in patients with severe COVID-19 infections, drawing attention to the relationship between COVID-19 and autoimmune diseases. COVID-19 shares similarities with autoimmune diseases in clinical manifestations, immune responses and pathogenic mechanisms. Robust immune reactions participate in the pathogenesis of both disease conditions. Autoantibodies as a hallmark of autoimmune diseases can also be detected in COVID-19 patients. Moreover, some patients have been reported to develop autoimmune diseases, such as Guillain--Barré syndrome or systemic lupus erythematosus, after COVID-19 infection. It is speculated that SARS-CoV-2 can disturb self-tolerance and trigger autoimmune responses through cross-reactivity with host cells. The infection risk and prognosis of COVID-19 in patients with autoimmune diseases remains controversial, but patient adherence to medication regimens to prevent autoimmune disease flares is strongly recommended.

Summary: We present a review of the association between COVID-19 and autoimmune diseases, focusing on similarities in immune responses, cross-reactivity of SARS-CoV-2, the development of autoimmune diseases in COVID-19 patients and the risk of COVID-19 infection in patients with preexisting autoimmune conditions.

Box 1

no caption available

FIGURE 1

Similar immune reactions in SARS-CoV-2 infection and autoimmune diseases. Both COVID-19 and autoimmune diseases present with various clinical symptoms involving different organs and systems, such as the haematological system, cardiovascular system, digestive system, kidneys, lungs, neurological system and pancreas. Organ damage is caused by uncontrolled immune response characterized by excessive production of cytokines and overactivation of immune cells, and the break of immune tolerance leading to the production of autoantibodies. SARS-CoV-2 infection can trigger cross-reactivity through molecular mimicry, leading to autoimmunity in patients with COVID-19.