Prevalence and Detection of Carbapenemases-producing Escherichiacoli strains isolated from clinical samples: A Cross-Sectional Survey in Jahrom, Southern, Iran

Background and Objectives: Bacterial resistance to antibiotics is increased morbidity and mortality worldwide. Acquired carbapenemases are emerging resistance determinants in Gram-negative pathogens, including E.coli. The most important mechanisms of carbapenem resistance are the production of carbapenemase encoding by Resistance genes KPC, NDM, GES, VIM and OXA-48 in Enterobacteriaceae bacteria. This study aims to assess the prevalence of carbapenemases in Escherichia coli strains by phenotype and genotype methods in Jahrom, Iran. Materials and Methods: In a cross-sectional study, A total of 314 E.coli strains obtained during 2015, from two university hospitals in Jahrom were studied. 178 strains were selected due to resistance or reduced susceptibilities to imipenem, meropenem and/or ceftazidime. The modified Hodge test (MHT) was performed for phenotypic identification. PCR was performed with specific primers for detection of Resistance genes KPC, NDM, GES, VIM and OXA-48 carbapenemase. Chi‑square test was used to find an association between the phenotypic identification, Resistance genes. The analysis was performed using the statistical package SPSS version 17.0. Results: Out of 178 strains were selected due to resistance or reduced susceptibilities carbapenems. Finally, the nineteen (10.7%) strains that were positive by MHT gave a positive result. These nineteen strains carried a bla VIM- type gene (0.3%), bla KPC- type gene (0.6%), bla GES- type gene (1.9%), bla NDM- type gene (2.2%), bla OXA-48- type gene (1.0%) and bla IMP-type gene was not detected. Conclusion: Carbapenems are the most effective antibiotics in the treatment of bacterial infections, hence the rapid identification of carbapenemase-producing strain and antibacterial susceptibility test in microbiology laboratories is critical. Reports of acquired carbapenemases are increasing worldwide among enterobacteria. Therefore, proper therapeutic methods should be used to prevent the increase of these resistances.

کلیدواژه ها:

Escherichia coli ، Carbapenemase ، Hodge test ، KPC ، VIM