Molecular epidemiology of KPC-2–producing Enterobacteriaceae (non– Klebsiella pneumoniae ) isolated from Brazil

Abstract In Brazil, since 2009, there has been an ever increasing widespread of the blaKPC-2 gene, mainly in Klebsiella pneumoniae . This study aims to assess the molecular epidemiology and genetic background of this gene in Enterobacteriaceae (non– K. pneumoniae ) species from 9 Brazilian states between 2009 and 2011. Three hundred eighty-seven isolates were analyzed exhibiting nonsusceptibility to carbapenems, in which the blaKPC-2 gene was detected in 21.4%. By disk diffusion and E-test, these isolates exhibited high rates of resistance to most of the antimicrobials tested, including tigecycline (45.6% nonsusceptible) and polymyxin B (16.5%), the most resistant species being Enterobacter aerogenes and Enterobacter cloacae . We found great clonal diversity and a variety of blaKPC-2 –carrying plasmids, all of them exhibiting a partial Tn 4401 structure. Therefore, this study demonstrates the dissemination of KPC-2 in 9 Enterobacteriaceae species, including species that were not previously described such as Pantoea agglomerans and Providencia stuartii.