Molecular epidemiology of VIM and IMP-producing Klebsiella isolates from urinary tract infection patients in an educational hospital

Abstract

Background and aim: Klebsiella is an opportunistic organism that is the cause of many nosocomial infections. The present study was designed to investigate the molecular epidemiology of Verona integron-encoded metallo-β-lactamase (VIM) and Imipenemase (IMP)-producing Klebsiella isolates in patients with urinary tract infection (UTI) in an educational hospitalin Shahrekord, in the center of Iran. Methods: In a cross-sectional study, from 234 urine samples, 80 isolates of Klebsiella were identified with biochemical tests. In order to determine the production of Metallo-β-lactamases (MBLs), Modified Hodge Test (MHT), EDTA Disc Synergy (EDS) test and AmpC disc test were performed. The frequency of VIM and IMP genes was determined after DNA-amplification with PCR by electrophoresis technique. Thereby, 16SrRNA was considered as an internal control in PCR.Results: Phenotypic tests showed that out of the 80 isolates, 18 (22. 5%), 18 (22. 5%) and 10­ (12.5%) isolates were positive for MHT, EDS and AmpC disc test, respectively. Following DNA amplification by PCR, the genes of interest were analyzed by electrophoresis technique. The findings were as follows: 22­ isolates (27.­5%) carried the VIM gene, but the IMP gene was not found in any of the isolates. Conclusions: Expansion of Klebsiella strains that produce MBLs is a severe threat to health centers and public health. The findings of this study showed that Klebsiella may produce MBLs. These enzymes can in turn degrade carbapenem antibiotics, which are considered as a last resort in the treatment of multidrug-resistant (MDR) infections.