Detection and reporting β-lactam resistance phenotypes in Escherichia coli and Klebsiella pneumoniae: a multicenter proficiency study in Spain

M. Carmen Conejo, C. Mata, F. Navarro, A. Pascual

Research output: Contribution to journalArticleResearchpeer-review

11 Citations (Scopus)

Abstract

The ability of 57 Spanish microbiology laboratories in detecting and reporting β-lactam resistance phenotypes in Escherichia coli and Klebsiella pneumoniae was evaluated. Laboratories received 6 well-characterized isolates expressing the most widespread extended-spectrum β-lactamases (ESBLs) in Spain (4 CTX-M type, 1 TEM type, and 1 SHV type), 3 isolates producing AmpC-type enzymes (2 plasmid mediated and 1 E. coli hyperproducing its chromosomal AmpC), and 3 quality control strains. Ninety-one percent of laboratories recognized all ESBL producers correctly, and therefore, low error rates were observed when testing cephalosporins and aztreonam. The highest error rates were observed with combinations of penicillin plus β-lactamase inhibitor, although more than 60% of cases were due to the interpretation made by the microbiologists. Correct recognition of all AmpC β-lactamase-producing strains occurred in only 47.4% of laboratories. These isolates were wrongly reported as ESBL producers and penicillinase hyperproducers in 7.6 % and 5.8% of cases, respectively. Detection of the AmpC-type phenotype by Spanish laboratories needs to be improved. © 2008 Elsevier Inc. All rights reserved.
Original languageEnglish
Pages (from-to)317-325
JournalDiagnostic Microbiology and Infectious Disease
Volume62
Issue number3
DOIs
Publication statusPublished - 1 Nov 2008

Keywords

  • β-Lactamase
  • AST
  • ESBL
  • Quality control

Fingerprint

Dive into the research topics of 'Detection and reporting β-lactam resistance phenotypes in Escherichia coli and Klebsiella pneumoniae: a multicenter proficiency study in Spain'. Together they form a unique fingerprint.

Cite this