DISTRIBUTION OF THE T-CELL ELEMENT OF THE IMMUNE SYSTEM IN POST-COVID PATIENTS WITH FIRST IDENTIFIED HYPERGLYCEMIA

Introduction. Post-Covid syndrome combines many adverse outcomes with often new-onset conditions, including type 2 diabetes mellitus (DM). The relevance of the study is the insufficient data on T-cell immunity in patients with hyperglycemia after COVID-19. The purpose of this study was to identify the characteristics of T-cell immunity in individuals with post-Covid syndrome and newly diagnosed carbohydrate metabolism disorders (CDM) in the post-Covid period. Materials and methods. The study included 100 patients (32 men and 68 women) aged from 38 to 70 years (mean age (M±m) was 59.40±8.80 years) with a verified post-COVID-19 condition. All patients were divided into three groups: group 1 – patients with concomitant newly diagnosed impaired glucose tolerance (IGT) in the post-Covid period (prior to SARS-CoV-2 infection, no increase in glycemia was detected according to primary medical documentation) (n=30) , group 2 – patients with concomitant newly diagnosed type 2 diabetes mellitus (n=30), group 3 – patients with the development of post-Covid syndrome without hyperglycemia (n=40). During the study, the following parameters were determined: CD45+, CD3+ (T lymphocytes), CD45+, CD3+, CD4+ (helper inducers), CD45+, CD3+, CD8+ (cytotoxic T lymphocytes), CD45+, CD3+, CD4+, CD25+, CD127- (T-regulatory cells), CD45+, CD3+, CD4+, CD25+ (T-lymphocytes - early activation), CD45+, CD3+, HLA-DR+ (T-lymphocytes - late activation). Results. Infection with SARS-CoV-2 with the subsequent development of post-Covid syndrome and persistent hyperglycemia (IGT, type 2 diabetes) in the post-Covid period was accompanied by a higher level of the total number of T-lymphocytes. A study of the T-lymphocyte population revealed changes in the subpopulation composition. In the group of patients with NMO, a significant increase in T-cytotoxic and T-regulatory cells was noted. More pronounced changes in the subpopulation composition were identified in the group of patients with newly diagnosed type 2 diabetes in the post-Covid period - an increase in the relative and absolute numbers of T-helper cells and T-cells of late activation of lymphocytes. Conclusions. Disorders of carbohydrate metabolism associated with COVID-19 are accompanied by changes in the subpopulation composition of T lymphocytes. In individuals with newly diagnosed type 2 diabetes in the post-Covid period, hyperactivation of the T-cell component of the immune system was revealed. Heterogeneous data were obtained in individuals with newly diagnosed impaired glucose tolerance, which requires further study of this group of patients.