Modification of the double-disk test for detection of Enterobacteriaceae producing extended-spectrum and AmpC β-lactamases

J. D D Pitout, Mark Reisbig, E. C. Venter, D. L. Church, Nancy D. Hanson

Research output: Contribution to journalArticle

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Detection of extended-spectrum β-lactamases (ESBLs) in AmpC-producing Enterobacteriaceae is problematic. A modification of the double-disk test (MDDT) has been developed for successful detection of ESBLs in gram-negative bacilli producing well-characterized β-lactamases as well as 212 clinical isolates of Enterobacter cloacae, Enterobacter aerogenes, Serratia marcescens, and Citrobacter freundii. MDDT accurately differentiated between ESBL producers and derepressed chromosomal AmpC mutants. MDDT provides a cost-effective alternative approach for clinical microbiology laboratories for routine susceptibility testing with simultaneous detection of ESBLs in Enterobacteriaceae.

Original languageEnglish
Pages (from-to)3933-3935
Number of pages3
JournalJournal of Clinical Microbiology
Issue number8
Publication statusPublished - Aug 1 2003


All Science Journal Classification (ASJC) codes

  • Microbiology (medical)
  • Microbiology

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