Abstrakt

Phenotypic and genotypic characterization of antibiotic resistance in Klebsiella pneumoniae isolated from patients admitted to a third-level hospital in Tehran, Iran.

Ali Badamchi, Reza khatabadi Farahani, Mehri Naghadalipoor, Mohammad Reza Etemadi, Azardokht Tabatabaie

Background: Metallo-Beta-Lactamase (MBL) and AmpC β-lactamases are hydrolyzing enzymes of penicillins, cephalosporins and carbapenemes. Nowadays, Carbapenem resistant Klebsiella pneumoniae is one of the important factors in hospital infections. The aim of this study was to determine the prevalence of MBL and AmpC β-lactamases production of K. pneumoniae in clinical specimens of patients referring to Rasool Akram Hospital in Tehran, between July 2016 and December 2017. Materials and Methods: Susceptibility of K. pneumoniae isolates for the common antibiotics was determined based on diffusion disc and CLSI protocol. Then MBL production was identified by phenotypic method of combined EDTA-meropenem disc. Lastly, the presence of blaKPC gene among isolated strains using specific primers was investigated among isolated strains using PCR method. Results: From total of 93 K. pneumoniae isolates, they showed the highest and lowest resistance for the antibiotics Ceftazidime (71%) and Imipenem (19.4%), respectively. The results of the combined disk method showed that 7.5% of the total samples (27 isolates) were MBL positive while blaKPC gene was detected in 38 strains (41%) by PCR method. most of them isolated from Urine specimens of patients admitted at ICU and Urology departments. Conclusion: The high prevalence of the blaKPC gene among K. pneumoniae isolates in current study further emphasize to implement the strategies including changing the pattern of the antibiotic use, in order to prevent the spread of such infections in hospitals.