Abstract:OBJECTIVE: To observe changes in T cell subsets in children with sepsis and their prognosis, and to investigate the clinical significance of these changes in the occurrence and development of sepsis. METHODS: Fifty children with severe sepsis and 150 children with general sepsis were enrolled as subjects, and 50 age-matched healthy children were included as controls. The percentages of CD3+, CD4+ and CD8+ T cells in peripheral blood and CD4+/CD8+ ratio were measured by flow cytometry. The pediatric critical illness score (PCIS) was calculated within 24 hours of admission. RESULTS: The children with severe sepsis showed significantly lower percentages of CD3+, CD4+ and CD8+ T cells CD4+/CD8+ ratio and PCIS than the controls and children with general sepsis (P<0.01). Among the 200 cases of sepsis, the percentages of CD3+, CD4+ and CD8+ T cells, CD4+/CD8+ ratio and PCIS were significantly lower in the cured group than in the deceased group. CONCLUSIONS: Children with sepsis have different degrees of cellular immunosuppression, and the degree of cellular immunosuppression is significantly correlated with the severity of the disease. Detection of T cell subsets in peripheral blood is of great significance for evaluating immune function and judging disease severity in children with sepsis.