Identification and Characterization of KPC-Producing Klebsiella pneumoniae in Clinical Isolates

The dissemination of carbapenemase-producing Klebsiella pneumoniae (KPC) strains is an increasing problem worldwide. KPC ß-lactamases are Ambler class A enzymes mostly plasmid-encoded; their global spread represents a threat to clinical patients care and public health. Between September-December 2012, have been isolated 60 Klebsiella pneumoniae strains that showed a decrease of susceptibility to carbapenems, collected from patients at the Provincial Laboratory of Clinical Microbiology ‘S. Agostino-Estense’ Hospital (Modena, Italy). Species identification and antimicrobial susceptibility testing were carried out using the Vitek 2 and studied for carbapenemases production using phenotypic confirmatory tests. The presence of carbapenemase genes were confirmed by PCR and sequencing. The localization of beta-lactamase genes was established by conjugation experiments. We reported the emergence of KPC-2-producing Klebsiella pneumoniae isolates PCR and sequencing experiments revealed the presence of blaKPC-2 gene in 56/60 isolates. The KPC-encoding plasmid was analysed by transconjugation experiments and DNA sequencing. The findings indicate the need to supplement surveillance systems based on susceptibility data with the surveillance of resistance mechanisms.