Vol. 5, Issue 1, Part A (2023)

The emergence of multidrug resistant organisms pose a great challenge to global health. Carbapenem group of drugs have been used as treatment therapy for these multidrug resistant organisms. Ceftazidime-avibactam is a newer combination consisting of ceftazidime, a 3^rd generation anti pseudomonal cephalosporin and avibactam, a beta lactamase inhibitor. Avibactam helps in restoring the antibacterial activity of ceftazidime against carbapenamase producing Enterobacterales. Ceftazidime-avibactam (CAZ-AVL) provides us a valuable strategy to combat carbapenem resistant infections especially in Enterobacterales. The objective of the study was to find out carbapenem resistant strains of Klebsiella pneumoniae from clinical isolates and to detect the carbapenamase activity by phenotypic and genotypic detection methods. Carbapenamase detection from the clinical isolates was done by meropenem hydrolysis test (mCIM). The resistant strains were evaluated for the activity of ceftazidime/avibactam by Estrip method. Molecular analysis of all the carbapenem resistant strains were done for blaOXA48 and blaKPC. Among 2500 isolates which were subjected to study from January-June 2022, 306 isolates grew Klebsiella pneumoniae among which 34 (11%) isolates were found to be multidrug resistant organisms (MDRO). Modified carbapenem inactivation method (mCIM) was used for carbapenamase activity. Ceftazidime/avibactam susceptibility was done using Estrip. 28(82.4%) isolates were found susceptible (≤8/4ug/ml) and 6(17.6%) isolates were found resistant (≥16/4ug/ml). Among CAZ/AVL resistant strains blaKPC was more prevalent than blaOXA48. In our study it was found that prevalence of OXA-48 was more than KPC among the resistant strains of Klebsiella pneumoniae and the susceptibility of ceftazidime/avibactam was more in Enterobacterales.