title: Population-based laboratory surveillance for AmpC beta-lactamase-producing Escherichia coli, Calgary.
abstract: In the Calgary Health Region during 2000-2003, prospective, active, population-based laboratory surveillance for all cefoxitin-resistant Escherichia coli isolates was performed. Isolates were screened with an inhibitor-based disk test, and plasmid-mediated types were identified by multiplex PCR with sequencing. A total of 369 AmpC beta-lactamase-producing E. coli isolates were identified; annual incidence rates were 1.7, 4.3, 11.2, and 15 per 100,000 residents for each year, respectively. AmpC beta-lactamase-producing E. coli was 5x more likely to be isolated from female than male patients across all age groups except < 1 year. Of these isolates, 83% were community onset, and urine was the principal site of isolation (90% of patients). PCR showed that 125 (34%) were positive for bla(cmy) genes; sequencing identified these enzymes to be CMY-2. In this large Canadian region, AmpC beta-lactamase-producing E. coli is an emerging community pathogen that commonly causes urinary tract infections in older women.
authors.affiliation: University of Calgary, Calgary, Alberta, Canada. johann.pitout@cls.ab.ca
authors.forename: Johann D D
authors.initials: JD
authors.lastname: Pitout
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Gregson
authors.forename: Deirdre L
authors.initials: DL
authors.lastname: Church
authors.forename: Kevin B
authors.initials: KB
authors.lastname: Laupland
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002170:Canada / Q000453:epidemiology; D002440:Cefoxitin / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D021821:Communicable Diseases, Emerging / Q000453:epidemiology*; D017714:Community-Acquired Infections / Q000453:epidemiology; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D004927:Escherichia coli Infections / Q000453:epidemiology*; D005260:Female; D005798:Genes, Bacterial; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018571:Sentinel Surveillance; D014556:Urine / Q000382:microbiology; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002440:Cefoxitin; C103022:beta-lactamase CMY-2; C048795:AmpC beta-lactamases; D001618:beta-Lactamases