Evaluating the prognostic effect of serum autoantibodies in relation to other blood biochemical markers in patients with different severity of COVID-19: Findings of a multicenter cohort study

Introduction: Coronavirus disease 2019 (COVID-19) is associated with abnormal immune responces. This study aimed to identify the prognostic effect of antiphospholipid antibodies on COVID-19 severity and survival. Materials: and Methods: This prospective cohort study was conducted on patients with a documented COVID-19 based on molecular techniques. Patients were grouped based on anti-nuclear antibody (ANA) positivity following COVID-19 diagnosis. Demographic, clinical, and laboratory findings were evaluated in all patients and every patients were followed for six months after the first positive test. Results: : A total of 239 patients (52.7% female and 47.3% male) with a mean age of 45.60 ± 11.50 years were evaluated. Groups significantly differed in MCV, PLT, WBC, neutrophil and lymphocyte count (p<0.05). ANCA (p<0.001), B2gl IgG (p=0.022), and anti ds DNA (p<0.001) were significantly more prevalent in negative group. lupus anticoagulant (LAC), B2gl IgM, p-Antineutrophil Cytoplasmic Antibodies (pANCA), cANCA, Anti-cardiolipin (aCL) IgM and aCL IgG positivity was significantly higher in positive group (p<0.001 each). Hospital admission and mortality rate were 20.1% and 1.7%, respectively. Majority of the patients (66.0%) improved, while 31.4% were admitted, and 2.6% died. ANA positive patients were more likely to be admitted (p<0.001) and less likely to improve (p<0.001) compared to negative group. Study groups did not differ in terms of mortality (p=0.096). B2gl IgG was the sole predictor for admission (p=0.030, OR= 3.93). Conclusions: : COVID-19 severity was associated with ANA and antiphospholipid antibodies (B2Gl IgG, LAC, ACL IgM and IgG, p and cANCa), while mortality was only associated with ANA. B2gl IgG could only predict hospital admission.