Molecular Analysis of Resistance Genes in Multidrug-Resistant Klebsiella Pneumoniae İsolates

Purpose: Development of antimicrobial resistance in Kelbsiella pneumoniae is a major problem in our country as well as in the whole world. Resistant K. pneumoniae is a bacterium that the World Health Organization has given critical priority in the list of the most dangerous pathogens for which antimicrobial drug development is needed. The aim of our study was to investigate carbapenem and colistin resistance genes in multidrug resistant K. pneumoniae isolates in a tertiary hospital in Turkey. Materials and Methods: Identification and antibiotic susceptibility tests were performed by Vitek-2 (bioMerieux, France). results for carbapenem and colistin were confirmed by gradient diffusion and microdilution methods. Carbapenemase and mcr genes were investigated by Polymerase Chain Reaction (PCR). Results: The blaNDM-1, blaOXA-48, blaKPC, blaVIM and blaIMP genes that cause resistance to carbapenem group antibiotics were tried to be determined by PCR in 69 isolates. As a result of the experiments, 54 (78%) of 69 isolates were positive for blaOXA-48 and 13 (19%) for blaNDM-1. KPC, VIM and IMP type beta-lactamases were not detected in any isolate. NDM-1 and OXA-48 type carbapenemases were found to be coexisting in 11 K. pneumoniae isolates. The mcr-1, mcr-2, mcr-3, mcr-4 and mcr-5 genes were not detected in any of the colistin resistant isolates. Conclusion: Colistin and carbapenem resistance mechanisms should be investigated by molecular methods in tertiary hospitals. The resistance profile data from the present study can be used as a knowledge base to understand the prevalent infection pattern in the hospital.