title: Modification of the double-disk test for detection of enterobacteriaceae producing extended-spectrum and AmpC beta-lactamases.
abstract: Detection of extended-spectrum beta-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 beta-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.
authors.affiliation: Department of Pathology & Laboratory Medicine, University of Calgary, Calgary T3C 0J5, Canada. johann.pitout@cls.ab.ca
authors.forename: J D D
authors.initials: JD
authors.lastname: Pitout
authors.forename: M D
authors.initials: MD
authors.lastname: Reisbig
authors.forename: E C
authors.initials: EC
authors.lastname: Venter
authors.forename: D L
authors.initials: DL
authors.lastname: Church
authors.forename: N D
authors.initials: ND
authors.lastname: Hanson
mesh_terms: D001426:Bacterial Proteins; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D004926:Escherichia coli / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification; D006801:Humans; D007753:Laboratories; D010641:Phenotype; D015203:Reproducibility of Results; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C117199:beta-lactamase TEM-61; C048795:AmpC beta-lactamases; D001618:beta-Lactamases