Purpose of the study. To investigate the features of lesions of the gastrointestinal tract in diff erent variants of the course of COVID-19 in children.Materials and methods. A single-center prospective study was carried out to study the clinical and laboratory manifestations of gastrointestinal tract (GIT) lesions in different variants of the course of COVID-19 in children. The study was carried out in the following groups: group No. 1 — pediatric patients with a verified diagnosis (according

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... o ICD 10) "U07.1. COVID-19 virus identified, confirmed by laboratory tests, regardless of the severity of clinical signs or symptoms ", n = 524; group No. 2 — pediatric patients with a verified diagnosis (according to ICD 10) "U10.9 Multisystem inflammatory syndrome associated with COVID-19, unspecified", n = 46. The article provides a brief description of the observations of the development of autoimmune pathologies (ulcerative colitis, autoimmune hepatitis) in pediatric patients, for whom a postponed COVID-19 infection could be a probable trigger.Results. The leading symptoms of the gastrointestinal tract in patients of group No. 1 were symptoms of acute gastroenteritis, registered in 37.6% of cases. Diarrhea was detected in 21.2% of cases, vomiting — in 16.5%; abdominal pain syndrome — 9.2%. These manifestations were statistically more significant in patients under one year of age, as well as in children of the first three years of life (p≤0.05). Gastrointestinal syndrome in patients of group No. 2 was registered in 67.4% of cases, with vomiting — 60.9% of cases, diarrheal syndrome — 23.9% of cases, abdominal pain syndrome — 82.6%. Other manifestations of the gastrointestinal tract in patients of this group were: reactive hepatitis — 69.6% of cases (average ALT — 98 (47; 347); AST — 107 (34; 347)), reactive pancreatitis — 60.8% of cases (average values of amylase — 127 (28; 269); lipase — 196 (47; 107)). These lesions were of a reactive inflammatory nature, with a probable immune development mechanism.