COVID-19 and Autoimmune Diseases

Yu Liu; Amr H. Sawalha; Qianjin Lu


Curr Opin Rheumatol. 2021;33(2):155-162. 

In This Article

Autoantibodies in Patients With COVID-19

Autoantibodies known to occur in a number of autoimmune diseases have been detected in patients with COVID-19 (Table 2). Pascolini et al.[14] determined the presence of antinuclear antibodies (ANA), anticytoplasmic neutrophil antibodies (ANCA) and antiantiphospholipid (APL) antibodies in 33 consecutive patients with COVID-19. The results showed that 45% of the patients were positive for at least one autoantibody and patients with positive autoantibodies tended to have a worse prognosis and a significantly higher respiratory rate at admission. The positive rate for ANA was 33%, the positive rate for anticardiolipin antibodies (IgG and/or IgM) was 24% and three patients tested positive for antiβ2-glycoprotein-I antibodies (IgG and/or IgM) (9%). However, ANCA was negative in all patients.[14] Coagulopathy is a threatening complication of SARS-CoV-2 infection. Recently, a cohort study was performed in Montefiore Medical Center to assess lupus anticoagulant positivity in COVID-19 patients. The researchers found that patients with COVID-19 had an increased incidence of lupus anticoagulant positivity compared with controls who tested negative by COVID-19 reverse transcriptase–PCR. In addition, COVID-19 patients with positive lupus anticoagulant had an increased rate of thrombosis.[51] Amezcua-Guerra et al.[52] also demonstrated a higher frequency of APL antibodies in patients with severe and critical COVID-19, and that the presence of APL antibodies seems to be associated with a hyperinflammatory state with extremely high levels of ferritin, C reactive protein and IL-6, and with pulmonary thromboembolism. The data discussed above provide a possible explanation for the hypercoagulable state in severe and critical COVID-19 cases and indicate that SARS-CoV-2 can induce autoimmune responses.

In COVID-19 patients presenting with neurological symptoms, the existence of autoantibodies against contactin-associated protein 2 (anti-Caspr2), ganglioside GD1b (anti-GD1b) and myelin oligodendrocyte glycoprotein (anti-MOG) has been shown in case reports or retrospective studies.[53,54] However, the clinical significance of these antibodies remains unclear. In addition, there are case reports demonstrating the presence of cold agglutinins and autoantibodies against RBC antigens in critically ill patients with COVID-19,[55] and the presence of anti-Ro/SSA antibodies in patients with aggravated COVID-19 pneumonia.[56] A research including 113 samples studied red cell antibodies by direct and indirect antiglobulin test (DAT or IAT). A positive DAT was found in 46% of COVID-19 patients, which was significantly higher than that in non-COVID-19 controls. The presence of red cell membrane bound immunoglobulins contributes to haemolytic anaemia and is related to the severity of anaemia in COVID-19.[57]