Evaluation of in vitro efficacy of aztreonam-nacubactam and cefepime-nacubactam against clinical isolates of Stenotrophomonas maltophilia.

Abstract

We evaluated the in vitro activity of aztreonam-nacubactam (ATM-NAC) and cefepime-nacubactam (FEP-NAC) against 53 clinical isolates of Stenotrophomonas maltophilia from blood cultures. Minimum inhibitory concentrations (MICs) were determined via broth microdilution. While ATM-NAC showed more significant MIC reduction, FEP-NAC also remarkably decreased MICs, despite cefepime being a substrate for L1 β-lactamase. These findings suggest the potential of β-lactam-NAC combinations as promising alternatives, warranting further in vivo studies to confirm clinical applicability.