Correlation between SARS-CoV-2 infection and autoimmune rheumatic diseases: a comprehensive analysis of blood biomarkers in COVID-19 patients.

OBJECTIVE

This study aimed to better understand the link between SARS-CoV-2 infection and autoimmune rheumatic diseases (ARDs) development by analyzing blood samples from 200 registered participants, and measuring biomarkers, such as cell-free DNA, MPO (myeloperoxidase), cathepsin S, and complement type 2 receptor.

PATIENTS AND METHODS

Blood samples were collected from 200 participants (100 females and 100 males; age range: 17-55 years). Participants were divided into five groups based on their COVID-19, SARS-CoV-2 nucleocapsid-specific IgG, and COVID-19 vaccination status. The Enzyme-Linked Immunosorbent Assay (ELISA) was used to identify the biomarkers.

RESULTS

ANOVA and t-tests revealed that the group of COVID-19 positive, SARS-CoV-2 nucleocapsid-specific IgG negative, and non-vaccinated individuals had the greatest average value for cathepsin S (p = 0.03). This suggests a correlation between the presence of COVID-19 and autoimmune disorders. The group with the greatest average value of cell-free DNA was the COVID-19-negative, SARS-CoV-2 nucleocapsid-specific IgG-negative, vaccinated group (p = 0.03). This may suggest that even though they had not contracted the disease, they may have had a stronger immune response to the virus since vaccines can stimulate an immune response even in individuals who have not been infected by the virus. Furthermore, the SARS-Cov-2 nucleocapsid-specific IgG+ and COVID-19 positive groups had higher levels of myeloperoxidase, a neutrophil protein linked to inflammation and tissue damage, suggesting a higher risk of autoimmune rheumatologic illnesses (p = 0.02).

CONCLUSIONS

The study suggests a correlation between COVID-19 status and the development of autoimmune disorders, as well as a potential link between a COVID-19 infection and a strong immune response. However, this study had limitations - the selection of participants and a small sample size, which offers potential for further research and examination.