[Alterations of peripheral blood T cell subsets in patients with sepsis and the clinical implications]

To observe the dynamic changes of CD3+, CD4+, and CD8+ T lymphocytes in the peripheral blood of patients with sepsis and discuss the clinical significance.

Sixty-four patients admitted in the Emergency Center and Emergency Intensive Care Unit of the Second Hospital of Wenzhou Medical University between August, 2007 and July, 2009 were enrolled in this study. CD3+, CD4+, and CD8+ T lymphocytes in the peripheral blood were detected by flow cytometry on days 1, 7 and 14 after admission, and the results were compared between the patients with improvement of the condition and those without improvement, with 20 healthy subjects as the control group.

On day 1 after admission, CD3+ and CD4+ T lymphocytes and CD4+/CD8+ T cell ratio were obviously lower in the 2 groups of patients with sepsis than in the control group (P<0.05), but no significant difference was found in CD8+ T lymphocytes. The sepsis patients with clinical improvement showed significant higher CD3+ and CD4+ T lymphocyte percentages and CD4+/CD8+ T cell ratio than those without improvement on day 1. In the patients with clinical improvement, CD3+ and CD4+T lymphocytes and CD4+/CD8+ T cell ratio increased gradually with time and till day 14, they were comparable with the control levels; in the patients without improvement, CD3+ and CD4+ T lymphocytes and CD4+/CD8+ T cell ratio showed no obvious alterations in the course of observation.

Immune imbalance occurs in patients with sepsis represented by lowered CD3+ and CD4+T lymphocyte percentages and CD4+/CD8+ T cell ratio in relation to the severity of the condition. CD3+ and CD4+ T lymphocytes and CD4+/CD8+ T cell ratio can be used as the indicators for assessing the severity of sepsis.