ceftazidime-avibactam activity against escherichia coli and klebsiella pneumoniae

Background and objectives: carbapenem-resistant enterobacteriaceae (cre) infections are extremely difficult to treat and have a high fatality rate. the study's primary goal was to determine the rate of ceftazidime-avibactam susceptibility using disc diffusion and e-test, as well as to evaluate the agreement between the two methods. materials and methods: a total of 124 multidrug-resistant (including carbapenem) escherichia coli and klebisella pneumoniae isolates were included. kirby bauer's disc diffusion and e-test were used as the testing methods in this study.results: in this study 37.5% and 33.9% of the isolates were susceptible to ceftazidime-avibactam by e test and disc diffusion respectively. there were five isolates which produced discordant results. among the 56 isolates there was 91% agreement between the two methods.conclusion: among the discordant isolates the alarming disparity in zone size was a significant concern. since cre infections are very common, an economical and practical method for testing ceftazidime-avibactam susceptibility is needed in all the clinical microbiology laboratories as it is a last resort drug.