One Virus, Two Diseases: Evaluation of Clinical and Immunological Differences in Covid-19 and Multisystem Inflammatory Syndrome Cases.

OBJECTIVES

This study aims to uncover early detection markers through the immunological analysis of children diagnosed with multisystem inflammatory syndrome (MIS-C) and coronavirus disease-2019 (COVID-19).

METHODS

We retrospectively analyzed immunological data from thirty-three MIS-C patients and an equivalent number of patients under the age of 18 with a positive polymerase chain reaction (PCR) test for COVID-19. These individuals were admitted to Ondokuz Mayis University between November 2020 and February 2021. In total, the study group consisted of 66 patients and an additional 10 healthy controls.

RESULTS

Lymphopenia, thrombocytopenia, anemia, and neutrophilia, along with elevated levels of ferritin, D-dimer, and C-reactive protein, were more pronounced in MIS-C patients (p<0.001). No significant disparities were found in serum IgG, A, M, and E concentrations. Notably, there was an increased proportion of B cells (p<0.001), an inversion of the CD4/CD8 ratio, and a marked presence of CD3+CD38+HLA-DR+active T cells (p=0.009) in the MIS-C cohort.

CONCLUSION

In the early diagnosis of MIS-C, lymphopenia, increase in B cells, reversal of CD4/CD8 ratio, and demonstration of CD3+CD38+HLA-DR+active T cells may be helpful.