title: The rapid detection of cefotaxime-resistantEnterobacteriaceaeby HPLC.
abstract: OBJECTIVE
  Antibiotic resistance mediated by extended-spectrum β-lactamases (ESBL) and AmpC β-lactamases is widespread and increasingly common, often rendering empiric antibiotic therapy ineffective. In septicemia, delays in initiating effective antibiotic therapy are associated with worse clinical outcomes. With current phenotypic antimicrobial susceptibility testing methods, there is often a delay of 18-24 h before the susceptibility of an isolate is known.
  
  
  RESULTS
  Using an HPLC assay, breakdown of the third-generation cephalosporin cefotaxime by ESBL- and AmpC- β-lactamase-producing organisms could be detected within 90 min with 86.4% sensitivity and 100% specificity; sensitivity for ESBL detection was 100%.
  
  
  CONCLUSIONS
  This assay could be readily established in any clinical laboratory with an HPLC to rapidly detect ESBL-producingEnterobacteriaceae.
authors.affiliation: Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand; Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Robinson
authors.affiliation: School of Pharmacy, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand.
authors.forename: Natalie J
authors.initials: NJ
authors.lastname: Medlicott
authors.affiliation: Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand; Southern Community Laboratories, Dunedin, New Zealand; Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand; Southern Community Laboratories, Dunedin, New Zealand.
authors.forename: James E
authors.initials: JE
authors.lastname: Ussher
keywords: AmpC β-lactamases; Enterobacteriaceae; HPLC; cephalosporin resistance; extended-spectrum β-lactamases (ESBL)