ABSTRACT
The problem of the incidence of new coronavirus infection in childhood is becoming increasingly important. At the same time, questions arise regarding the peculiarities of the pathogenesis of COVID-19 in children. The aim of the research was to study the clinical and immunological features of COVID-19 in children hospitalized with a severe course of the disease. Material and methods. We examined 53 children from 0 to 15 years old, hospitalized with suspected new coronavirus infection at Children's Clinical Hospital No. 3 in Novosibirsk from October to December 2020. Determination of specific IgM and IgG antibodies to SARS-CoV-2 antigens in serum blood was carried out using the ELISA method. SARS-CoV-2 virus RNA in nasopharyngeal and oropharyngeal swabs was determined using commercial kits for PCR diagnostics. A z-test was used to compare relative numbers. The significance level was taken equal to 5% (p=0.05). Results and discussion. All examined children hospitalized with suspected COVID-19, regardless of the duration of the disease, had specific IgG antibodies to SARS-CoV-2 antigens, which confirms earlier contact with the new coronavirus in relation to the time of the examination. In 63.6% of cases, specific IgM antibodies of the class to SARS-CoV-2 were detected in the blood serum, in 6% of cases the result was doubtful. IgM antibodies were not detected in blood serum in 30.3% of patients. The results obtained for the determination of IgG and IgM antibodies to SARS-CoV-2 antigens may reflect the atypical nature of seroconversion in COVID-19. An extremely diverse clinical symptomatology was revealed, including, in addition to catarrhal syndrome and intoxication syndrome, abdominal, meningeal, and articular syndromes. In 24.3% of children, polymorphic exanthema was detected, which may be a manifestation of the systemic nature of damage to the vascular wall. Conclusion. With serologically confirmed SARS-CoV-2 etiology of the infectious process in the examined children, an extremely diverse clinical symptomatology was revealed, which, most likely, may be associated with multiple organ damage.Copyright © Transplantologiya. The Russian Journal of Transplantation.All right reserved.