Monitoring of Antibody Levels Following SARS-CoV-2 Infection in Children and Late Adolescents with Inflammatory Rheumatic Diseases

Objective: We monitored the severe acute respiratory syndrome-coronavirus-2 antibody levels in patients with inflammatory rheumatic diseases (IRD) and healthy children. Methods: Healthy children and patients under 21 who were initially seropositive, were included in the study. Antibody levels of all subjects were measured again after the third and sixth months by the ELISA method. In this process, their symptoms were also questioned in terms of coronavirus disease-2019. Results: The study included 35 participants (female/male: 1.69) (healthy control group: 10, patient group not receiving biological therapy: 19, patient group receiving biological therapy: 6). Their mean age was 14.27 +/- 5.49 years. Of the participants, 13 (37.1%) had a history of symptomatic infection, and 4 (11.4%) had a history of hospitalization. At the end of the six-month, a significant decrease was found in the immunoglobulin G levels of the participants (p=0.002). While no significant decrease was observed in the first trimester (p=0.085), there was a sharp decrease in the second trimester (p<0.001). Age, sex, presence of IRD and use of biological agents did not affect this decrease. Conclusion: Although they decrease rapidly in the second trimester, we showed that antibodies acquired by infection in healthy children and children with IRD mostly stay at an acceptable level after six months. These data can be used to schedule vaccination programs. Besides, we showed that IRD and biological drugs do not affect the decrease in antibody levels. Therefore, no additional precautions may be required regarding vaccination in this patient group.