Abstract: Objective  To explore the diagnostic and prognostic  value of serum procalcitonin (PCT),  the level of neutrophil CD64,  the percentage of T lymphocyte subsets,  SOFA score and APACHE Ⅱ score in patients with sepsis.Methods  A  total of  72 patients with sepsis were divided into the sepsis group and the septic shock group. The level of serum PCT,  neutrophil percentage of CD64 and T lymphocyte subsets were measured,  and  APACHE Ⅱ score  and SOFA score (five  indicators) were calculated  at the first day and the seventh day after admission.Logistic regression analysis and the receiver operating characteristic curve were applied to  the  probing of the relationship between those indicators and outcomes.Results  ①Total mortality rate was 31.9%.The mortality rates  of the two group were significantly different,  with that of the sepsis group being  19.57% and septic shock group 53.85% (P=0.019). ②Compared with the  sepsis group,  the four indicators  (namely, PCT，CD65（%）, APACHE Ⅱ  and  SOFA)  of the septic shock group  were all higher within the first 24 hour,  but its  ratio of T lymphocyte CD4+/CD8+ were lower than that of the  sepsis group (P<0.05). ③Compared with  the survival group,  the abovementioned  four indicators of the nonsurvival group within the first 24 hour were higher, but  its ratio of T lymphocyte CD4+/CD8+ was  relatively  lower (P<0.05). ④Serum PCT and APACHE score were positively correlated at different time（r=0.702， 0.637，P＜0.01） , so were the percentge of CD64 and APACHE Ⅱ (r=0.676， 0.622，P<0.01),  as well as  SOFA  and APACHE Ⅱ（r=0.676， 0.622，P＜0.01）,   while  the ratio of T lymphocyte CD4+/CD8+  and APACHE score were negatively  related(P<0.01).⑤The five  indicators above  were all independent factors（P＜0.05）  affecting  the prognosis of sepsis patients and the more indicators  combined,  the higher sensitivity and specificity.Conclusion  The serum PCT,  the ratio of T lymphocyte CD4+/CD8+,  neutrophil CD64(%),  APACHE Ⅱ score and SOFA score can be used to assess the condition and risk of patients with    sepsis. Combined together,  these factors can have  higher sensitivity and specificity in terms of the prognosis of patients with sepsis.

Key words: sepsis, procalcitonin, neutrophil CD64, T lymphocyte subsets, APACHE Ⅱ score, SOFA score, prognosis