Efficacy of cefoperazone-sulbactam as a component of combination therapy for carbapenem-resistant Acinetobacter baumannii bloodstream infection in intensive care units: a multicenter retrospective propensity score-matched study.

Background: In this study, we aimed to evaluate the efficacy of cefoperazone-sulbactam-containing (CSC) combination therapy for carbapenem-resistant Acinetobacter baumannii (CRAB) bloodstream infections (BSI) patients in intensive care unit (ICU).

Methods: This multicenter, retrospective cohort study initially included 407 patients with CRAB BSI in the ICU between 2015 and 2019. Patients were divided into the CSC- and non-cefoperazone-sulbactam-containing (NCSC) groups. Outcomes including mortality, clinical failure, and microbiological eradication were compared after time-window bias adjustment and propensity score matching.

Results: There was no statistical difference in baseline characteristics and disease severity between the CSC (n = 50) and NCSC groups (n = 150) after propensity score matching. The CSC group had significantly lower rates of all-cause mortality (30.0% vs. 50.0%, p = 0.014) and clinical failure (32.0% vs. 52.0%, p = 0.015) on day 28 than the NCSC group. The CSC regimen was an independent protective factor against 28-day clinical failure (adjusted odds ratio (aOR) = 0.281, 95% confidence interval [CI] = 0.091-0.864, p = 0.027). Kaplan-Meier analysis showed that the CSC group had a significantly longer survival time than the NCSC group (log-rank test, p = 0.028). The subgroup analysis of clinical factors associated with 28-day mortality showed that female patients and those with body mass index > 25, non-smoker status, and C-reactive protein < 30 especially favored the CSC regimen instead of the NCSC regimen.

Conclusions: As an alternative to ampicillin-sulbactam, cefoperazone-sulbactam could be considered as components of combination therapy for critically ill patients with CRAB BSI.