Genetic diversity of Klebsiella pneumoniae producing KPC isolated from several hospitals in the State of São Paulo

Abstract

 KPC (Klebsiella pneumoniae Carbapenemase) is an enzyme that confers      resistance to all beta-lactams, including carbapenems. Klebsiella pneumoniaeproducing      KPC causing nosocomial outbreaks were first reported in New York      (2004) and nowadays this KPC-producing microorganism is disseminated      worldwide. KPC-producing K. pneumoniae isolated in 2005 was first      described in Brazil and from 2009 has spread through several hospitals in      Sao Paulo State, as well as other states. The aim of this study was to evaluate      the genetic diversity of KPC-producing K. pneumoniae isolates from several      hospitals in Sao Paulo State performing MLST and PFGE to detect clonal      spread within and among hospitals. A total of 100 isolates of K. pneumoniae      from several hospitals in Sao Paulo State sent to Adolfo Lutz Institute and      previously confirmed in our laboratory as KPC producers were selected      and subjected to Pulsed Field Gel Eletrophoresis (PFGE) and Multi-Locus      Sequence Typing (MLST). Eleven PFGE profiles were detected and the      profile A was the prevalent, found in 61% of the strains. MLST showed 8      different sequence types (ST) and the ST437 was predominant in 73% of the      isolates, followed by ST11 (11%), ST340 (7%), ST258 (3%), ST442 (2%) E      ST101 (1%) and two new STs were described, ST1044 and ST1046. PFGE      and MLST data showed how strains are disseminated among hospitals and      among cities increasing the dissemination of resistance mechanisms such as      ESBL-producing, carbapenemases and 16S rRNA methylases. ST437, ST11,      ST340 and ST258 belong to the same clonal complex denominated CC258      that are globally disseminated and associated with the production of KPC and      CTX-M. The prevalence of the clone belonging to ST437 and to the PFGE A      profile was observed in 59% of the isolates. This may suggest a correlation      between PFGE and MLST results, althought it was observed different PFGE      profiles in the same ST and different ST in the same PFGE profile.