Longitudinal analysis of the in vitro activity of ceftazidime-avibactam vs. Enterobacteriaceae, 2012-2016.
J Glob Antimicrob Resist. 2019 Jul 08;:
Authors: Ramalheira E, Stone GG
BACKGROUND: The in vitro activities of ceftazidime-avibactam and comparator agents were analyzed against 59,828 isolates of Enterobacteriaceae collected by 190 centers from all global regions except North America from 2012 to 2016 as part of the International Network For Optimal Resistance Monitoring (INFORM) global surveillance program.
METHODS: Antimicrobial susceptibility testing was performed using CLSI broth microdilution panels at a central reference laboratory except for isolates collected in China, which were tested using frozen, dehydrated broth microdilution panels at a central lab in China. The presence of extended-spectrum ß-lactamases (ESBLs) was confirmed using multiplex PCR assays.
RESULTS: Ceftazidime-avibactam was the most active agent against all Enterobacteriaceae (MIC90 ≤1 mg/L, ≥98.4% susceptibility). High rates of susceptibility (>88%) were observed amongst C. freundii, Citrobacter spp., Enterobacter spp., E. coli, K. pneumoniae and K. oxytoca to colistin, meropenem, amikacin and tigecycline. Ceftazidime-avibactam showed consistent in vitro activity against ESBL-positive E. coli (N = 5,674; MIC90 0.5 mg/L, 99.5% susceptible), K. pneumoniae (N = 7,097, MIC90 2 mg/L, 98.7% susceptible) and K. oxytoca (N = 565, MIC90 1 mg/L, 96.8% susceptible). Isolates identified as metallo-ß-lactamase-positive (N = 242) were not susceptible to ceftazidime-avibactam, but were susceptible to tigecycline (76.9%) and colistin (N = 194, 92.8%).
CONCLUSIONS: Clinical isolates of Enterobacteriaceae, including ESBL-positive phenotypes, collected globally (excluding North America) from 2012 to 2016 were highly susceptible to ceftazidime-avibactam, suggesting it is a useful agent for serious infections caused by multidrug-resistant organisms belonging to the Enterobacteriaceae when therapeutic options are limited.
PMID: 31295583 [PubMed - as supplied by publisher]