INTRODUCTION

Sepsis is a life-threatening complication resulting from a dysregulated host response to a serious infection, of which bacteria are the most common cause. A rapid differentiation of the gram negative (G)/gram positive (G) pathogens facilitates antibiotic treatment, which in turn improves patients' survival.

METHODS

We performed a prospective, observational study of adult patients in intensive care unit (ICU) unit and underwent the analysis of peripheral blood lymphocyte subsets, cytokines and other clinical indexes. The enrolled 94 patients were divided into no infection group (n=28) and bacterial sepsis group (n=66), and the latter group was subdivided into G (n=46) and G (n=20) sepsis subgroups.

RESULTS

The best immune biomarker which differentiated the diagnosis of G sepsis from G sepsis, included activation markers of CD69, human leukocyte antigen DR (HLA-DR) on CD3CD8T subset. The ratio of CD3CD4CD69T/CD3CD8CD69T (odds ratio (OR): 0.078(0.012,0.506), P = 0.008), PCT>0.53 ng/ml (OR: 9.31(1.36,63.58), P = 0.023), and COCP<26.5 mmol/l (OR: 10.99(1.29, 93.36), P = 0.028) were predictive of G sepsis (versus G sepsis), and the area under the curve (AUC) was 0.947. Additionally, the ratio of CD3CD4CD69T/CD3CD8CD69T ≤ 0.2697 was an independent risk factor for poor ICU discharge in G sepsis patients (HR: 0.34 (0.13, 0.88), P=0.026).

CONCLUSION

We conclude that enhanced activation of T cells may regulate the excessive inflammatory response of G bacterial sepsis, and that T cell activation profiles can rapidly distinguish G sepsis from G sepsis and are associated with ICU discharge.