Investigation of oxa-48-like genes in carbapenemase producing klebsiella spp. strains

INTRODUCTION AND OBJECTIVE: In recent years, increase of carbapenem resistant Enterobacteriaceae isolates is known worldwide. The aim of this study is to identify OXA-232, OXA-181, OXA-162, OXA-204, OXA-244, OXA-163 and OXA-245 gene regions in OXA-48 like carbapenemase producing Klebsiella pneumoniae isolates. MATERIALS AND METHODS: The isolates used for our study were taken from SEAH Medical Microbiology Laboratory collection. Identification and antibiotic susceptibility analyzes were evaluated with the VITEK 2 automated system. Carbapenemase production isolates was determined by the Modified Hodge Test. The MIC values of each isolates were determined by broth microdilution method. Afterwards in these isolates, and isolates containing the OXA-48 gene region were identified by qPCR. The strains suspected of owning OXA-48 variants by HRMA method were sequencing to determine which variants were present. RESULTS: In carbapenemase producing K. pneumoniae strains, categorical agreement for VITEK 2 and microdilution were obtained for imipenem, meropenem and ertapenem, 82%, 77%, and 90% respectively. By qPCR method, OXA-48 gene locus was found to be positive in 45 of 100 K. pneumoniae strains. To identify OXA-48 variants, 45 strains that were positive by PCR were interpreted by HRMA method. Afterwars, Sanger sequencing revealed that 41 strains contained OXA-48/OXA-245 gene regions, 2 strains OXA-181 and 2 strains determined OXA-244 gene regions. CONCLUSION:As a result of our study, OXA-48 positivity was found to be 45%. These strains 4.4% were found to contain OXA-181 and 4.4% were found to contain OXA-244 regions. It is important that we study because OXA-48 variants in our country are the first to be comprehensively studied, epidemiological studies because of contribution, provide a basis for the establishment of indigenous diagnostic kits for carbapenemase detection, which saves time in the laboratory and improves clinical outcomes.