Antimicrobial susceptibility of pseudomonas aeruginosa to ceftazidime-avibactam, ceftolozane-tazobactam, piperacillin-tazobactam, and meropenem stratified by U.S. census divisions: Results from the 2017 INFORM program

Abstract

Pseudomonas aeruginosa isolates (n 1,909) were collected from 70 U.S. medical centers, and their susceptibilities were tested using the broth microdilution method. Ceftazidime-avibactam (MIC 50 /MIC 90 , 2/8 mg/liter) and ceftolozane-tazobactam (MIC 50 /MIC 90 , 0.5/2 mg/liter) were the most active (i.e., had the highest susceptibility rates) compounds after colistin, with national susceptibility rates of 96.9% and 97.5%, respectively. Overall, piperacillin-tazobactam (MIC 50 /MIC 90 , 4/128 mg/liter) and meropenem (MIC 50 /MIC 90 , 0.5/16 mg/liter) were active against 77.5% and 76.0% of the isolates, respectively. Susceptibility variations across census divisions were documented for many antimicrobials.