Alterations and clinical significance of peripheral blood T lymphocyte subsets in patients with septic acute kidney injury

Objective To investigate the alterations of peripheral blood T lymphocyte subsets in patients with sepsis and septic acute kidney injury, and explore the clinical significance. Methods Fifty-five patients with sepsis and forty-three patients with septic acute kidney injury were enrolled in this study. At the same period, thirty healthy subjects were enrolled as the control group. T lymphocyte subsets including CD3+ T, CD4+ T, CD8+ T cells, and CD4+ T/CD8+ T in peripheral blood were detected by flow cytometry, and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) were graded within twenty-four hours after admission. Then, correlation of the APACHE Ⅱ scores and T lymphocyte subsets was analyzed. Results In the septic acute kidney injury group, peripheral blood CD3+ T, CD4+ T cell percentages, and CD4+ T/CD8+ T ratio were significantly lower than those in the control group and the sepsis group (all P<0.05). In the septic acute kidney injury group with stage 3, CD3+ T, CD4+ T cell percentages, and CD4+ T/CD8+ T ratio in the patients were significantly lower than those in stage 1 and stage 2 (all P<0.05). In the septic acute kidney injury group, CD3+ T, CD4+ T cell percentages, and CD4+ T/CD8+ T ratio were significantly lower in dead group than those in survival group (all P<0.05). APACHE Ⅱ scores in patients with sepsis were significantly negatively correlated with peripheral blood CD4+ T cell percentages and CD4+ T/CD8+ T ratio (r=-0.645, -0.492, allP<0.05). Conclusions There are varying degrees of cellular immune imbalance in patients with sepsis and septic acute kidney injury, characterized by decline of circulating CD3+ T, CD4+ T cell percentages, and CD4+ T/CD8+ T ratio. CD4+ T cell percentages and CD4+ T/CD8+ T ratio are closely related to the severity and prognosis of septic acute kidney injury. Key words: Sepsis/CO/IM; Kidney diseases/CO/IM; T-lymphocyte subsets