Detection of the carbapenemase GIM-1 in Enterobacter cloacae in Germany

J Antimicrob Chemother. 2013 Mar;68(3):558-61. doi: 10.1093/jac/dks447. Epub 2012 Nov 14.

Abstract

Objectives: To characterize the mechanisms involved in reduced susceptibility to carbapenems in two Enterobacter cloacae clinical isolates.

Methods: Two E. cloacae isolates recovered from different regions in Germany and showing reduced susceptibility to carbapenems were analysed. Susceptibility testing, conjugation, transformation assays, plasmid analysis, sequencing and molecular typing using rep-PCR were performed.

Results: The two clinical isolates carried the bla(GIM-1) gene and showed resistance to ertapenem, with variable MIC values of imipenem and meropenem. The isolates were clonally unrelated. The bla(GIM-1) gene was located on self-transferable and non-typeable plasmids. Both isolates harboured distinct plasmids and integron structures containing the bla(GIM-1) gene cassette. Interestingly, one of the two plasmids was able to replicate in Pseudomonas aeruginosa, demonstrating its broad host range.

Conclusions: This is the first identification in E. cloacae of the bla(GIM-1) gene, which is responsible for reduced susceptibility to carbapenems. We showed that this gene, previously identified in P. aeruginosa, was located in a different genetic background in E. cloacae. The bla(GIM-1) gene might spread quite efficiently in Enterobacteriaceae and P. aeruginosa, as it is difficult to detect and in addition is located on conjugative plasmids.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / genetics*
  • Carbapenems / pharmacology*
  • Conjugation, Genetic
  • Enterobacter cloacae / drug effects
  • Enterobacter cloacae / enzymology*
  • Enterobacter cloacae / genetics
  • Enterobacter cloacae / isolation & purification
  • Enterobacteriaceae Infections / microbiology
  • Germany
  • Humans
  • Male
  • Microbial Sensitivity Tests
  • Molecular Typing
  • Plasmids / analysis
  • Polymerase Chain Reaction
  • Pseudomonas aeruginosa / genetics
  • Sequence Analysis, DNA
  • Transformation, Genetic
  • beta-Lactam Resistance*
  • beta-Lactamases / genetics*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Carbapenems
  • beta-Lactamases
  • carbapenemase