Molecular epidemiology of Enterobacteriaceae producing extended-spectrum beta-lactamase in a French university-affiliated hospital

Int J Antimicrob Agents. 2003 Aug;22(2):128-33. doi: 10.1016/s0924-8579(03)00098-0.


We conducted a retrospective study to investigate the epidemiology of Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE) in our hospital. We determined the occurrence of extended-spectrum beta-lactamase (ESBL) in Enterobacteriaceae over a 2-year period. We also characterised ESBLs by isoelectric focusing (IEF) and investigated the epidemiological relatedness of EBLSE by pulsed field gel electrophoresis (PFGE). During this period, 70 patients were colonised/infected with one or several strains of EBLSE, giving a crude incidence of 0.095 per 1000 patient-days. We found that ESBL-producing Enterobacter aerogenes were the main source of ESBLE dissemination. Indeed, 59.5% of ESBLE were E. aerogenes and 21.9% of the other ESBLE resulted from a plasmid transfer originating from E. aerogenes. IEF and PFGE analysis demonstrated that the dissemination of ESBL from E. aerogenes in our hospital was due to a single clone that always harbours TEM-24. This emphasises the importance of standard contact isolation precautions and the early detection of ESBLE-colonised patients in high risk departments like intensive care units.

MeSH terms

  • DNA, Bacterial / genetics
  • DNA, Bacterial / isolation & purification
  • Drug Resistance, Bacterial / genetics
  • Electrophoresis, Gel, Pulsed-Field
  • Enterobacter aerogenes / drug effects
  • Enterobacter aerogenes / enzymology
  • Enterobacter aerogenes / genetics
  • Enterobacteriaceae / drug effects
  • Enterobacteriaceae / enzymology*
  • Enterobacteriaceae / genetics*
  • Enterobacteriaceae / isolation & purification
  • Enterobacteriaceae Infections / epidemiology*
  • Enterobacteriaceae Infections / microbiology*
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology
  • France / epidemiology
  • Hospitals, University
  • Humans
  • Klebsiella Infections / epidemiology
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / enzymology
  • Klebsiella pneumoniae / genetics
  • Molecular Epidemiology
  • Retrospective Studies
  • beta-Lactamases / biosynthesis*


  • DNA, Bacterial
  • beta-Lactamases