Analysis of carbapenemases genes of carbapenem-resistant Klebsiella pneumoniae isolated from Tehran heart center

Abstract

Background and Objectives: Emerging of carbapenem-resistant Klebsiella pneumoniae (CRKP) is one of the major con- cerns among healthcare systems. This study aimed to investigate the antibiotic susceptibility pattern and carbapenemase genes of carbapenemase-producing K. pneumoniae isolates obtained from Iranian hospitalized patients. Materials and Methods: This study was performed on 71 CRKP strains isolated from different clinical specimens collected in Tehran Heart Center (Tehran, Iran). A Modified Hodge test (MHT) was done for the detection of carbapenemase-producing K. pneumoniae. The presence of bla method. KPC , bla VIM , bla IMP , bla , and bla OXA-48 -type carbapenemases was evaluated by the PCR Results: We identified 8.82% (71/805) of K. pneumoniae isolates as CRKP by MHT test. The antibiotic susceptibility indi- cated that all isolates were resistant to imipenem, meropenem, cefotaxime, ceftazidime, cefepime, ceftriaxone, cephalothin, ciprofloxacin, and augmentin, and then mostly resistant to aztreonam, cefoxitin, gentamicin, and trimethoprim/sulfamethox- azole with 98.6%, 98.6%, 97.2%, and 94.4%, respectively. The lowest resistance was related to amikacin with 46.5% (33/71 isolates). The level of imipenem MIC for all carbapenem-resistant isolates was estimated ≥32 µg/mL. Among positive iso- lates for carbapenemase genes, the most frequent gene was bla . It was found in 48 (67.6%) isolates followed by bla VIM in 28 (39.4%) isolates. bla IMP, bla , and bla KPC genes were identified in 19 (26.8%), 13 (18.3%) and 5 (7.0%) isolates, respectively. These genes were not detected in nine isolates. Conclusion: The relatively high frequency of some carbapenemase genes suggests major concern about the emergence of isolates containing carbapenem resistance genes as a potential health threat.

Topics & Concepts