In vitro activity of ceftazidime-avibactam against 338 molecularly characterized gentamicin-nonsusceptible Gram-negative clinical isolates obtained from patients in Canadian hospitals

Antimicrob Agents Chemother. 2015;59(6):3623-6. doi: 10.1128/AAC.00364-15. Epub 2015 Mar 30.

Abstract

The mechanism of aminoglycoside resistance among 338 gentamicin-nonsusceptible Gram-negative bacteria (207 Enterobacteriaceae and 131 Pseudomonas aeruginosa) was assessed, and the in vitro activity of ceftazidime-avibactam against these isolates was determined. Aminoglycoside-modifying enzymes were detected in 91.8% of Enterobacteriaceae and 13.7% of P. aeruginosa isolates. A single strain of Klebsiella pneumoniae harbored a 16S rRNA methylase (ArmA). The ceftazidime-avibactam MIC90 values were 0.5 μg/ml (MIC, ≤8 μg/ml for 100% of isolates) and 16 μg/ml (MIC, ≤8 μg/ml for 87.8% of isolates) against gentamicin-nonsusceptible Enterobacteriaceae and P. aeruginosa isolates, respectively.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Azabicyclo Compounds / pharmacology*
  • Canada
  • Ceftazidime / pharmacology*
  • Drug Combinations
  • Gentamicins / pharmacology*
  • Gram-Negative Bacteria / drug effects*
  • Hospitals
  • Humans
  • Microbial Sensitivity Tests
  • RNA, Ribosomal, 16S / genetics

Substances

  • Anti-Bacterial Agents
  • Azabicyclo Compounds
  • Drug Combinations
  • Gentamicins
  • RNA, Ribosomal, 16S
  • avibactam, ceftazidime drug combination
  • Ceftazidime