Investigation of NDM metallo-beta-lactamase and CMY-2 Amp. β-lactamase production in Escherichia coli and Enterobacter spp. isolated from human

AbstractNew Delhi metallo-beta-lactamase (NDM) and CMY-2-AmpC β-lactamase are among the most important resistance factors against carbapenem and beta-lactam antibiotics. Considering the few studies in Iran, here NDM and CMY-2 production inEscherichia coli (E.coli) andEnterobacter isolates were evaluated. Acquired resistance profiles of isolates were determined based on the new definitions as multi-drug resistant (MDR), extensively drug-resistant (XDR) and pan-drug resistant (PDR). In carbapenem-resistant strains, minimum inhibitory concentration (MIC) of different antibiotics by Etest method and the clonal relationship using enterobacterial repetitive intergenic consensus (ERIC)-PCR were determined. The frequency ofblaNDM andblaCMY-2 was examined using phenotypic methods and PCR. Among 466E.coli and 135Enterobacter isolates, 42 and 28 different resistotypes were observed, respectively. InE.coli strains, 88 and 0.2% of isolates were MDR and XDR, respectively and these percentages inEnterobacter strains were 91.9 and 1.5 but no PDR strain was detected. The most efficient antibiotics were tigecycline, colistin, carbapenems, chloramphenicol, minocycline, fosfomycin, piperacillin/tazobactam, and amikacin. In addition, 9 (1.9%) ofE.coli and 9 (6.7%) ofEnterobacter isolates were non-susceptible to carbapenems. The 6E.coli and 2Enterobacter strains were positive for AmpC by phenotypic test butblaCMY-2 gene wasn ’t detected. TheblaNDM-1 gene was detected in two strains (oneE.coli a...
Source: Comparative Clinical Pathology - Category: Pathology Source Type: research