Leukocyte kinetics during the early stage acts as a prognostic marker in patients with septic shock in intensive care unit

The leukocytes play an important role in immune function during sepsis. We performed a retrospective study to investigate if leukocytes kinetics was associated with survival in critically ill patients with septic shock in intensive care unit (ICU). Patients with septic shock from January 1, 2014 to June 30, 2018 in our ICU were included. We extracted the demographic, clinical and laboratory data, comorbidities from our clinical database. The number of white blood cell, neutrophil and lymphocyte on day 1 and day 3 after diagnosis were collected and neutrophil to lymphocyte ratios (NLR) were calculated. Our primary outcome was 28-day mortality. Univariate and multivariate logistic regression models and cox proportional risk model were used to analyze the association between the leukocytes kinetics during first 3 days after ICU admission and the day-28 mortality. A total of 1245 septic shock patients with a 28-day mortality of 35.02% were included into analysis. There were no significant difference of lymphocyte number (0.83 ± 0.02 vs 0.80 ± 0.04, P = .552) between survival and non-survivals on day 1. However, the lymphocyte counts was significantly lower (0.95 ± 0.03 vs 0.85 ± 0.04, P = .024) on the third day. Both multivariate logistic and Cox regression analysis showed that lymphocyte counts on day 3 were associated with day-28 mortality. Moreover, Kaplan–Meier survival analysis revealed that increasing in lymphocyte counts and decreasing WBC, neutrophils and NLR during the first 3 days after diagnosis were associated with longer survival. Leukocytes kinetics during the first 3 days is a valuable prognostic marker in patients with septic shock in the ICU.