Dissemination of SHV-12 and CTX-M-type Extended-Spectrum Beta-Lactamases Among Clinical Isolates of Escherichia Coli and Klebsiella Pneumoniae and Emergence of GES-3 in Korea

J Antimicrob Chemother. 2005 Oct;56(4):698-702. doi: 10.1093/jac/dki324. Epub 2005 Sep 2.


Objectives: To assess the prevalence and genotypes of Ambler class A extended-spectrum beta-lactamases (ESBLs) in Korea.

Methods: Clinical isolates of Escherichia coli and Klebsiella pneumoniae collected from 12 Korean hospitals during February-July 2003 were evaluated. Antimicrobial susceptibilities were determined by disc diffusion and agar dilution methods, and the putative ESBL-producing strains were tested by the double-disc synergy method. Detection of genes encoding class A beta-lactamases was performed by PCR amplification, and the PCR products were subjected to direct sequencing.

Results: The double-disc synergy test showed positive results in 9.3% (23/246) of E. coli and 23.0% (55/239) of K. pneumoniae isolates. The most prevalent types of Ambler class A ESBLs in E. coli isolates were CTX-M-15 (n = 4) and CTX-M-3 (n = 3), and those in K. pneumoniae isolates were SHV-12 (n = 30) and CTX-M-3 (n = 13). Two isolates produced both SHV-12 and GES-3, simultaneously.

Conclusions: CTX-M-type and/or SHV-12 ESBL-producing E. coli and K. pneumoniae isolates are spreading, and a GES-type ESBL has emerged in Korea.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Drug Resistance, Bacterial
  • Escherichia coli / drug effects
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Escherichia coli / isolation & purification
  • Escherichia coli Infections / epidemiology
  • Escherichia coli Infections / microbiology*
  • Hospitals
  • Humans
  • Klebsiella Infections / epidemiology
  • Klebsiella Infections / microbiology*
  • Klebsiella pneumoniae / drug effects
  • Klebsiella pneumoniae / enzymology*
  • Klebsiella pneumoniae / genetics
  • Klebsiella pneumoniae / isolation & purification
  • Korea / epidemiology
  • Microbial Sensitivity Tests
  • beta-Lactamases / genetics*


  • Anti-Bacterial Agents
  • beta-lactamase CTX-M-14
  • beta-lactamase CTX-M-15
  • beta-lactamase CTX-M-3
  • beta-lactamase SHV-12
  • beta-Lactamases
  • beta-lactamase GES-3, Klebsiella pneumoniae