White blood cell counts have an impact on septic patient outcome followed by polymyxin-b immobilized fiber with direct hemoperfusion

Introduction

The mortality rate of severe sepsis and septic shock is varied and high (25 to 70%). In our institute, the indication for polymyxin-B immobilized fiber with direct hemoperfusion (PMX-DHP) has been that circulatory failure (systolic blood pressure <90 mmHg or required catecholamines and high lactacidemia) continued despite following early goal-directed therapy by the Surviving Sepsis Campaign guidelines 2012.

Methods

This study included 80 patients with severe sepsis or septic shock due to abdominal infection retrospectively. These subjects were divided into two groups: those with WBC counts <4,000 (L-group: 64 patients) and those with WBC counts >12,000 (H-group: 16 patients). Mean arterial pressure, WBC counts, platelet counts, interleukin-6 (IL-6), and plasminogen activator inhibitor-1 (PAI-1) were measured immediately before the initiation and after the completion of PMXDHP. Statistical analysis was performed using the chi-squared test for background factors, with Wilcoxon's rank-sum test for comparison within a group, and Mann-Whitney's U test for comparison between groups. The significance level was set at P <0.05.

Results

The mortality rate of 28 days in the L-group was 32.8%, and was 18.8% in the H-group. Mean arterial pressure increased significantly (P <0.01) in the H-group compared with the L-group. WBC counts in the L-group increased and in the H-group decreased (P <0.01) during PMXDHP treatment. Platelet counts in both groups decreased significantly (P <0.01).There was no significant difference between before and after PMX-DHP in IL-6 levels. On the other hand, IL-1ra decreased significantly before and after PMX-DHP. Also, IL-6 and IL-1ra in the L-group were significantly higher than those in the H-group at the start of PMXDHP. PCT values in the L-group were increased compared with the H-group at the start of PMX-DHP (P <0.01). PCT in the L-group increased significantly (P <0.01), but no significant changes in the H-group. PAI1 showed no significant changes before and after PMX-DHP and no changes in both groups at the start of PMX-DHP.

Conclusion

The mortality rate of the L-group tended to be higher than that of the H-group. Inflammatory and anti-inflammatory cytokines in the L-group were higher than those of the H-group. These results indicate that leukopenia (WBC <4,000) in severe sepsis patients leads to more severe outcome and hypercytokinemia than leukocytosis (WBC >12,000) in severe sepsis patients.