CLINICAL-IMMUNOLOGICAL MANIFESTATIONS AND CHARACTERISTICS OF MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN WITH COVID-19

Abstract

The article presents information on a study conducted to study the clinical and laboratory parameters of multisystem inflammatory syndrome (MIS-S) and the characteristics of the disease course in children who had COVID-19. For this purpose, 120 sick children aged 1 to 17 years were included in the study. The methods of examining patients included anamnestic and epidemiological data, as well as clinical, instrumental and laboratory studies. The examinations were carried out during the acute period of the disease. The diagnosis of the disease was made based on the clinical diagnostic criteria of the World Health Organization (WHO) and the US Centers for Disease Control and Prevention. All patients were tested for the presence of IgM and IgG antibodies to COVID-19 using polymerase chain reaction (PCR) of a nasopharyngeal swab, a rapid antigen test or ELISA in accordance with a typical diagnostic protocol for detecting contact with the COVID-19 virus. 108 patients had a positive SARS-CoV2 IgG test result and a negative SARS-CoV2 IgM test result. Four patients had positive COVID-19 PCR test results, and eight patients had positive SARS-CoV-2 rapid antigen test results. Our results indicate that MIS-C is caused by previous COVID-19 infection, and these results are consistent with many literature data.
According to laboratory tests, neutrophilia, lymphopenia, thrombocytosis, and an increase in ESR were observed in the blood serum. Elevated levels of CRP, procalcitonin, ferritin, D-dimer, pro-BNP, troponin I, and fibrinogen were also detected. This condition was assessed as a criterion for the severity of the disease. It was found that the level of CRP, procalcitonin, D-dimer, troponin I, and ferritin in the blood is directly proportional to the severity of the clinical course of the disease. The receiver operating characteristic curve for pro-BNP and D-dimer yielded the largest area under the curve of any other biomarker.