Emergence of clonally related Klebsiella pneumoniae isolates of sequence type 258 producing plasmid-mediated KPC carbapenemase in Norway and Sweden

J Antimicrob Chemother. 2009 Apr;63(4):654-8. doi: 10.1093/jac/dkp018. Epub 2009 Feb 13.


Background: The class A carbapenemase KPC has disseminated rapidly worldwide, challenging the treatment of Gram-negative infections. This report describes the first KPC-producing Klebsiella pneumoniae isolates identified in Norway (n=6) and the second isolate from Sweden.

Methods: Antimicrobial susceptibility profiles were determined using Etest. PCR and sequencing were used to determine the bla(KPC) variant, the surrounding genetic structure and the presence of AmpC and extended-spectrum beta-lactamase genes. PFGE and multilocus sequence typing (MLST) were used for epidemiological comparisons. Localization of bla(KPC) was investigated by S1 nuclease digestion, followed by PFGE and Southern blot hybridization.

Results: All isolates expressed a multidrug-resistant phenotype with some variability in the carbapenem susceptibility profile. The Norwegian isolates carried bla(KPC-2), while the Swedish isolate carried bla(KPC-3). All isolates carried TEM-1, but were negative for bla(CTX-M) and bla(AmpC) genes. SHV-11 and SHV-12 were detected in the Norwegian isolates, while the Swedish isolate carried only SHV-11. Isolates from four patients were associated with import from Greece (n=3) and Israel. The other isolates were probably associated with local transmissions. PFGE and MLST showed that the isolates were clonally related, with three isolates displaying ST258, a single locus variant of ST11 previously associated with the clonal spread of CTX-M-15-producing K. pneumoniae in Hungary. In all isolates, bla(KPC) was located on plasmids as part of isoform a of Tn4401.

Conclusions: The emergence of KPC-producing isolates of K. pneumoniae in Norway and Sweden is associated with multiple import events and probable local transmission of a successful multiresistant ST258 clone, closely related to the CTX-M-15-producing ST11 clone previously described in Hungary.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / biosynthesis*
  • Bacterial Proteins / genetics
  • Blotting, Southern
  • Carbapenems / pharmacology*
  • DNA Fingerprinting
  • DNA Transposable Elements
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial*
  • Electrophoresis, Gel, Pulsed-Field
  • Humans
  • Klebsiella Infections / microbiology*
  • Klebsiella pneumoniae / drug effects*
  • Klebsiella pneumoniae / enzymology*
  • Klebsiella pneumoniae / isolation & purification
  • Microbial Sensitivity Tests
  • Norway
  • Plasmids
  • Sequence Analysis, DNA
  • Sweden
  • beta-Lactamases / biosynthesis*
  • beta-Lactamases / genetics


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Carbapenems
  • DNA Transposable Elements
  • DNA, Bacterial
  • beta-Lactamases
  • carbapenemase