[Frequency of extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase genes in Escherichia coli and Klebsiella pneumoniae over a three-year period in a University Hospital in Korea].

BACKGROUND The aim of this study was to determine the yearly prevalence and genotype distribution of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae collected over a 3-yr period in Gwangju, Korea. METHODS Clinical isolates of E. coli and K. pneumoniae collected at Chosun University Hospital from September 15, 2005 to September 14, 2008 were evaluated. Antimicrobial susceptibility testing was performed using the Vitek II system (bioMérieux, USA) and agar dilution methods. Screening for ESBL and AmpC β-lactamase genes was performed using PCR amplification of plasmid DNA followed by direct sequencing of the PCR products. RESULTS The percentage of ESBL-producing isolates was 12.6% (196/1,550) for E. coli and 26.2% (294/1,121) for K. pneumoniae. The ESBL gene sequencing results showed that the most prevalent ESBL types were CTX-M (93.5%) and SHV (12.9%) in E. coli, and SHV (73.2%) and CTX-M (46.3%) in K. pneumoniae. The most common ESBL in E. coli was CTX-M-15-like, followed by CTX-M-14-like, SHV-2a-like, and SHV-12-like. The most prevalent ESBL type in K. pneumoniae was SHV-12, followed by CTX-M-14-like and CTX-M-15-like. Fifty-one percent (21/41) of ESBL-producing K. pneumoniae with ESBL types verified by sequencing also had DHA-1-like AmpC β-lactamases. However, none of the ESBL-producing E. coli was positive in the AmpC β-lactamase PCR analysis. CONCLUSIONS In this study, the most common types of class A ESBLs identified were CTX-M-15-like in E. coli and SHV-12-like in K. pneumoniae.

[1]  D. Yong,et al.  [Emergence of CTX-M-12 and A Novel CTX-M Type Extended-Spectrum beta-Lactamaseproducing Klebsiella pneumoniae.]. , 2006, The Korean journal of laboratory medicine.

[2]  Sang-Nae Cho,et al.  Emergence and Wide Dissemination of CTX-M-type ESBLs, and CMY-2- and DHA-1-type AmpC β-Lactamases in Korean Respiratory Isolates of Klebsiella pneumoniae , 2005, Journal of Korean medical science.

[3]  Seok Hoon Jeong,et al.  Clonal spread of both oxyimino-cephalosporin- and cefoxitin-resistant Klebsiella pneumoniae isolates co-producing SHV-2a and DHA-1 beta-lactamase at a burns intensive care unit. , 2006, International journal of antimicrobial agents.

[4]  Kenneth S. Thomson,et al.  Comparison of Phoenix and VITEK 2 Extended-Spectrum-β-Lactamase Detection Tests for Analysis of Escherichia coli and Klebsiella Isolates with Well-Characterized β-Lactamases , 2007, Journal of Clinical Microbiology.

[5]  Geun Ho Kang,et al.  Molecular Characterization of Extended-Spectrum Beta-Lactamases Produced by Clinical Isolates of Klebsiella pneumoniae and Escherichia coli from a Korean Nationwide Survey , 2004, Journal of Clinical Microbiology.

[6]  S. Koo,et al.  [Prevalence of extended-spectrum beta-lactamases in Escherichia coli and Klebsiella pneumoniae from Daejeon]. , 2007, The Korean journal of laboratory medicine.

[7]  F. Baquero,et al.  Integron Content of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains over 12 Years in a Single Hospital in Madrid, Spain , 2005, Antimicrobial Agents and Chemotherapy.

[8]  Jung Hun Lee,et al.  Investigation of extended‐spectrum β‐lactamases produced by clinical isolates of Klebsiella pneumoniae and Escherichia coli in Korea , 2004, Letters in applied microbiology.

[9]  N. Hanson,et al.  Detection of Plasmid-Mediated AmpC β-Lactamase Genes in Clinical Isolates by Using Multiplex PCR , 2002, Journal of Clinical Microbiology.

[10]  E. Kim,et al.  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. , 2005, The Journal of antimicrobial chemotherapy.

[11]  K. Ko,et al.  Prevalence and characterization of extended-spectrum beta-lactamase-producing Enterobacteriaceae isolated in Korean hospitals. , 2008, Diagnostic microbiology and infectious disease.

[12]  Jungmin Kim,et al.  CTX-M and SHV-12 beta-lactamases are the most common extended-spectrum enzymes in clinical isolates of Escherichia coli and Klebsiella pneumoniae collected from 3 university hospitals within Korea. , 2005, FEMS microbiology letters.

[13]  Chang Ki Kim,et al.  Spread of CTX-M-type extended-spectrum beta-lactamases among bloodstream isolates of Escherichia coli and Klebsiella pneumoniae from a Korean hospital. , 2009, Diagnostic microbiology and infectious disease.

[14]  Juwon Kim,et al.  Prevalence of the extended-spectrum beta-lactamase and qnr genes in clinical isolates of Escherichia coli. , 2009, The Korean journal of laboratory medicine.

[15]  J. Herrmann,et al.  Diversity of CTX-M beta-lactamases and their promoter regions from Enterobacteriaceae isolated in three Parisian hospitals. , 2002, FEMS microbiology letters.

[16]  정석훈,et al.  Investigation of extended-spectrum β-lactamases produced by clinical isolates of Klebsiella pneumoniae and Escherichia coli in Korea , 2004 .

[17]  S. Kwon,et al.  Dissemination of transferable CTX‐M‐type extended‐spectrum β‐lactamase‐producing Escherichia coli in Korea , 2005, Journal of applied microbiology.

[18]  Wonkeun Song,et al.  CTX-M-14 and CTX-M-15 enzymes are the dominant type of extended-spectrum β-lactamase in clinical isolates of Escherichia coli from Korea , 2009, Journal of medical microbiology.