COVID-19 and immunological dysregulation: can autoantibodies be useful?

Abstract Coronavirus disease 2019 (COVID-19) is often associated with interstitial pneumonia However, there is insufficient knowledge on the presence of autoimmune serological markers in patients with COVID-19 We analyzed the presence and role of autoantibodies in patients with COVID-19-associated pneumonia We prospectively studied 33 consecutive patients with COVID-19, 31 (94%) of whom had interstitial pneumonia, and 25 age- and sex-matched patients with fever and/or pneumonia with etiologies other than COVID-19 as the pathological control group All patients were tested for the presence of antinuclear antibodies (ANAs), anti-antiphospholipid antibodies (APLs), and anti-cytoplasmic neutrophil antibodies (ANCAs) Clinical, biochemical, and radiological parameters were also collected Fifteen of 33 (45%) patients tested positive for at least one autoantibody, including 11 who tested positive for ANAs (33%), 8 who tested positive for anti-cardiolipin antibodies (IgG and/or IgM) (24%), and 3 who tested positive for anti-?2-glycoprotein antibodies (IgG and/or IgM) (9%) ANCA reactivity was not detected in any patient Patients that tested positive for autoantibodies had a significantly more severe prognosis than other patients did: 6 of 15 (40%) patients with autoantibodies died due to COVID-19 complications during hospitalization, whereas only 1 of 18 (5 5%) patients who did not have autoantibodies died (p = 0 03) Patients with poor prognosis (death due to COVID-19 complications) had a significantly higher respiratory rate at admission (23 breaths per minute vs 17 breaths per minute;p = 0 03) and a higher frequency of autoantibodies (86% vs 27%;p = 0 008) In conclusion, autoantibodies are frequently detected in patients with COVID-19 possibly reflecting a pathogenetic role of immune dysregulation However, given the small number of patients, the association of autoantibodies with an unfavorable prognosis requires further multicenter studies