Genotyping and molecular investigation of plasmid-mediated carbapenem resistant clinical <i>Klebsiella pneumoniae</i> isolates in Egypt

Abstract

<abstract> <p><italic>Klebsiella pneumoniae</italic> is a multidrug-resistant nosocomial pathogen. Carbapenem resistance is mediated mainly by enzymes carried on transmissible plasmids causing their dissemination among other members of <italic>Enterobacteriaceae</italic>. This study aimed to molecularly detect carbapenem resistance genes in <italic>K. pneumoniae</italic> clinical isolates, genotype them using ERIC-PCR, and investigate plasmid transformation of resistant genes by using ERIC-PCR and sequencing.</p> <sec> <title>Methods</title> <p>Antimicrobial resistance of sixty carbapenem-resistant <italic>K. pneumoniae</italic> strains was evaluated by using the disc diffusion method. Five carbapenemases' genes were amplified by conventional PCR. Genotyping was performed using ERIC-PCR. Gene transformation was performed for the five genes to sensitive isolates. Wild and transformed isolates were genetically investigated using ERIC-PCR and sequencing.</p> </sec><sec> <title>Results</title> <p>Carbapenem resistance in our isolates was associated with high resistance to all tested antibiotics. The 60 <italic>K. pneumoniae</italic> isolates were divided into 6 resistor types. The prevalence of <italic>KPC, IMP, VIM, NDM</italic>, and <italic>OXA-48</italic> genes were 17%, 63%, 93%, 85% and 100%, respectively. Dendrogram analysis showed 57 distinct patterns, arranged in three clusters. The five genes were transformed successfully into sensitive isolates. ERIC profiles of wild and transformed isolates showed cluster A contained all the wild isolates, and cluster B contained all transformed isolates. Genetic sequences of the 5 genes reflected high genetic similarity with the GenBank reference genes before plasmid transformation; however, a distinguishable decrease of genetic similarity was observed after transformation.</p> </sec><sec> <title>Conclusion</title> <p>Plasmid-mediated carbapenem resistance in <italic>K. pneumoniae</italic> and its dissemination among different strains is a real threat to public health.</p> </sec></abstract>