In vitro antibacterial activity of the ceftazidime-avibactam combination against enterobacteriaceae, including strains with well-characterized β-lactamases.

ABSTRACT: The novel β-lactamase inhibitor avibactam is a potent inhibitor of class A, class C, and some class D enzymes. The in vitro antibacterial activity of the ceftazidime-avibactam combination was determined for a collection of Enterobacteriaceae clinical isolates; this collection was enriched for resistant strains, including strains with characterized serine β-lactamases. The inhibitor was added either at fixed weight ratios to ceftazidime or at fixed concentrations, with the latter type of combination consistently resulting in greater potentiation of antibacterial activity. In the presence of 4 μg/ml of avibactam, the ceftazidime MIC50 and MIC90 (0.25 and 2 μg/ml, respectively) were both below the CLSI breakpoint for ceftazidime. Further comparisons with reference antimicrobial agents were pe

SUBMITTER: Levasseur P 

PROVIDER: S-EPMC4356809 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature