A cohort study of the impact of carbapenem-resistant Enterobacteriaceae infections on mortality of patients presenting with sepsis

Abstract

The objective of this study is to evaluate the impact of carbapenem-resistant Enterobacteriaceae (CRE) infection on sepsis 30-day mortality. A retrospective cohort of patients >18 years old with sepsis and organ dysfunction or septic shock was conducted. Univariate analysis was done for variables potentially related to 30-day mortality, and the ones with P values of <0.05 were included in a backward stepwise hierarchic Cox regression model. Variables that remained with P values of <0.05 were retained in the model. A total of 1,190 sepsis episodes were analyzed. Gram-negative bacterial infections occurred in 391 (68.5%) of 571 patients with positive cultures, of which 69 (17.7%) were caused by a CRE organism. Patients with CRE infections had significantly higher 30-day mortality: 63.8% versus 33.4% (P < 0.01). CRE infection was also associated with a lower rate of appropriate empirical therapy (P < 0.01) and with the presence of septic shock (P < 0.01). In the hierarchic multivariate model, CRE remained significant when controlling for demographic variables, comorbidities, and infection site but lost significance when controlling for septic shock and appropriate empirical therapy. Older age (P < 0.01), HIV-positive status (P < 0.01), cirrhosis (P < 0.01), septic shock (P < 0.01), higher quick sepsis-related organ failure assessment (quick-SOFA) (P < 0.01), and appropriate empirical therapy (P = 0.01) remained in the final model. CRE infections were associated with higher crude mortality rates. A lower rate of appropriate empirical therapy and late diagnosis were more frequent in this group, and improvement of stewardship programs is needed.