Differences in suppression of regrowth and resistance despite similar initial bacterial killing for meropenem and piperacillin/tazobactam against Pseudomonas aeruginosa and Escherichia coli

We described bacterial killing and resistance emergence at various fixed concentrations of meropenem and piperacillin/tazobactam against Pseudomonas aeruginosa and Escherichia coli. Time-kill studies were conducted utilizing nine isolates and a large range of concentrations. Within each strain and antibiotic, initial killing was similar, with concentrations ≥2×MIC. At many (strain-specific) concentrations causing substantial initial killing, regrowth occurred at 24-48h. For remaining concentrations, growth typically remained suppressed (

Source: Diagnostic Microbiology and Infectious Disease - January 3, 2018 Category: Microbiology Authors: Phillip J. Bergen, J ürgen B. Bulitta, Fekade B. Sime, Jeffrey Lipman, Megan J. McGregor, Nada Millen, David L. Paterson, Carl M.J. Kirkpatrick, Jason A. Roberts, Cornelia B. Landersdorfer Tags: Antimicrobial Susceptibility Study Source Type: research