Characterizing carbapenemase production in Enterobacterales through combined disk test and genetic profiling

Abstract

: Carbapenem-resistant  (CRE) are major organisms amongst the critical group of drug-resistant bacteria and are associated with high morbidity and mortality. With limited treatment options, the detection and characterization of carbapenemase is important for appropriate management. This study aims to characterize carbapenemase produced by  using combined disk test and their molecular profiling. : All carbapenem-resistant isolated from various clinical samples were included in the study. Carbapenemase production was characterized by observing synergy on combining meropenem disk with beta-lactamase inhibitors like phenylboronic acid, EDTA, and cloxacillin, following which genetic profiling was done using multiplex PCR.: Out of 445  isolated, 104 (23.4%) were carbapenem-resistant. The most common CRE isolated was  (62 out of 104) followed by  (40 out of 104) and 2 out of 104 CRE isolates were  species. Co-production of NDM and OXA-48-like enzymes (39.4%) was the most common mechanism followed by NDM alone (19.2%) and OXA-48 alone (16.3%). NDM was the most common gene detected overall with 72 out of 104 CRE (69.2%) isolates showing its presence, followed by OXA-48 present in 63 of 104 (60.6%) isolates.: Metallo-beta-lactamases (NDM) was the predominant type of carbapenemase gene detected among the isolates, with the co-production of NDM and OXA-48 enzymes being the most common mechanism of resistance.