In-Hospital Mortality After Blood Purification With and Without Acrylonitrile-Co-Methallyl Sulfonate Surface-Treated Membrane for Pneumonia-Associated Sepsis: A Retrospective Cohort Study

Background: Cytokine removal therapy is one of the available therapies for sepsis. Acrylonitrile-co-methallyl sulfonate surface-treated (AN69ST, sepXiris®) membrane has cytokine adsorption capacity and has been widely used for treating sepsis in Japan. The aim of this study was to compare the effects of continuous renal replacement therapy (CRRT) with AN69ST membrane and conventional CRRT for patients with pneumonia-associated sepsis.Methods: We conducted a retrospective cohort study using the Diagnosis Procedure Combination database, a nationwide inpatient database in Japan. We identified adult patients who were hospitalized due to pneumonia and received CRRT within 2 days of admission from September 2014 to March 2017. We included patients who received CRRT with AN69ST membrane within 2 days of admission in the treatment group (AN69ST group); those who received CRRT with other membranes within 2 days of admission were included in the control group (non-AN69ST group). Propensity score matching was used to compare in-hospital mortality between the two groups.Results: Eligible patients (n=2,393) were categorized into the AN69ST group (n=631) or the non-AN69ST group (n=1,762). The overall in-hospital mortality rate in pneumonia patients treated with CRRT was 38.9%. Propensity score matching created a matched cohort of 545 pairs of patients. The in-hospital mortality rate was significantly lower in the AN69ST group than in the non-AN69ST group (35.8 vs. 41.8%, p=0.046).Conclusion: Our data suggest that CRRT with the AN69ST membrane was associated with a significantly lower in-hospital mortality than CRRT with standard membranes among patients with pneumonia-associated sepsis.