Journal Article

Community and hospital spread of <i>Escherichia coli</i> producing CTX-M extended-spectrum β-lactamases in the UK

N. Woodford, M. E. Ward, M. E. Kaufmann, J. Turton, E. J. Fagan, D. James, A. P. Johnson, R. Pike, M. Warner, T. Cheasty, A. Pearson, S. Harry, J. B. Leach, A. Loughrey, J. A. Lowes, R. E. Warren and D. M. Livermore

in Journal of Antimicrobial Chemotherapy

Published on behalf of British Society for Antimicrobial Chemotherapy

Volume 54, issue 4, pages 735-743
Published in print October 2004 | ISSN: 0305-7453
Published online October 2004 | e-ISSN: 1460-2091 | DOI: https://dx.doi.org/10.1093/jac/dkh424
Community and hospital spread of Escherichia coli producing CTX-M extended-spectrum β-lactamases in the UK

More Like This

Show all results sharing these subjects:

  • Medical Oncology
  • Critical Care

GO

Show Summary Details

Preview

Objectives: During 2003, the Health Protection Agency's Antibiotic Resistance Monitoring and Reference Laboratory began to receive isolates of Escherichia coli for confirmation of extended-spectrum β-lactamase production with a phenotype implying a CTX-M-type β-lactamase, i.e. MICs of cefotaxime ≥8-fold higher than MICs of ceftazidime. Many were referred as being from community patients. We examined 291 CTX-M-producing isolates from the UK and investigated the genetic basis of their phenotype.

Methods: PCR was used to detect alleles encoding CTX-M enzymes and to assign these to their blaCTX-M phylogenetic groups. Selected alleles were sequenced. Producers were compared by analysis of banding patterns generated by pulsed-field gel electrophoresis of XbaI-digested genomic DNA. MICs were determined by an agar dilution method or by Etest.

Results: Of 291 CTX-M-producing E. coli isolates studied from 42 UK centres, 70 (24%) were reportedly from community patients, many of whom had only limited recent hospital contact. Community isolates were referred by 12 centres. Two hundred and seventy-nine (95.9%) producers contained genes encoding group 1 CTX-M enzymes and 12 contained blaCTX-M-9-like alleles. An epidemic CTX-M-15-producing strain was identified, with 110 community and inpatient isolates referred from six centres. Representatives of four other major strains also produced CTX-M-15, as did several sporadic isolates examined. Most producers were multi-resistant to fluoroquinolones, trimethoprim, tetracycline and aminoglycosides as well as to non-carbapenem β-lactams.

Conclusions: CTX-M-producing E. coli are a rapidly developing problem in the UK, with CTX-M-15 particularly common. The diversity of producers and geographical scatter of referring laboratories indicates wide dissemination of blaCTX-M genes. Because of the public health implications, including for the treatment of community-acquired urinary tract infections, the spread of these strains—and CTX-M-15 β-lactamase in particular—merits close monitoring.

Keywords: ESBLs; CTX-M β-lactamases; community infections; molecular epidemiology

Journal Article.  4505 words.  Illustrated.

Subjects: Medical Oncology ; Critical Care

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.