Detection of SARS-CoV-2 antibodies in pediatric patients: An Iranian referral hospital-based study.

Background: As the extent of the pandemic and its seroprevalence pattern has been less clarified in pediatrics to date, we aimed to conduct this study to investigate the clinical and laboratory characteristics of COVID-19 in Iranian children, with a focus on evaluating the antibody prevalence and its relation with the laboratory tests.

Methods: All children with highly suspected COVID-19 were included. Anti-nucleoprotein SARS-CoV-2 were measured using SARS-CoV-2 immunoglobulin M (IgM) and SARS-CoV-2 IgG ELISA kits. Hypothesis testing was carried out through SPSS to unravel any association between the measurement tools and important clinical and laboratory characteristics.

Results: In this study, 254 patients were evaluated and 117 cases (46%) were male. The nucleic acid detection results for patient 55 were negative, but the IgM and IgG results were positive. Totally, 190 patients were tested for IgM in which only 14 (7.3%) had positive tests. Positive IgG was detected in 51 (20%) out of 254 patients; among them, 30 patients had negative SARS-CoV-2 RT-PCR (59%). Lower level of platelets in IgG positive group in comparison with the IgG negative group was observed (P value: 0.015). Moreover, higher alanine aminotransferase (ALT) was observed in the in IgG positive group (P value: 0.02). In patients with positive IgM, relative hypocalcemia (median of 8.25; IQR: 8.02-8.62) was found which appeared to be significant (P value: 0.02).

Conclusion: This is the first largest study describing the SARS-CoV-2 seropositivity among children in Iran and provides important insight about the COVID-19 infection in children.