Evaluation of Ceftazidime-Avibactam Resistance Rates in Multi-Drug Resistant Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa Strains in Intensive Care Units

Introduction: The increase in infections due to multidrug-resistant gram -negative bacteria and the difficulties in the treatment of these infections are a major concern. In this study, we aimed to evaluate the in vitro efficacy of ceftazidime/avibactam against multidrug-re- sistant Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli clinical isolates. Materials and Methods: Multidrug-resistant P. aeruginosa, K. pneumoniae, and E. coli isolated from various samples sent to our labora- tory from intensive care units were included in the study. Identification and antimicrobial susceptibility of isolates were performed using automated systems. Results: A total of 201 multidrug-resistant gram -negative bacteria were isolated during the study period. Of these, 138 were from K. pneumoniae, 47 from P. aeruginosa, and 16 from E. coli. It was determined that 81.6% of the isolates were susceptible to ceftazidime/ avibactam, without making any distinction of species. The susceptibility of E. coli, K. pneumoniae, and P. aeruginosa strains to ceftazidime/avibactam was 93.8%, 95.7%, and 36.2%, respectively. Conclusion: Our findings suggest that ceftazidime/avibactam may be promising in the treatment of infections caused by E. coli and K. pneumoniae strains. The high resistance found in P. aeruginosa isolates suggests that ceftazidime/avibactam should not be used as an empirical treatment and the conditions of use in this manner should be reevaluated. The data obtained in this study will contribute to the clinical use of these agents in our country.