title: Prevalence and characterization of extended-spectrum β-lactamase- and AmpC β-lactamase-producing Escherichia coli: results of the CANWARD 2007-2009 study.
abstract: The national prevalence of extended-spectrum β-lactamase (ESBL)-producing (2007: 3.4%, 2008: 4.9%, 2009: 4.3%) and AmpC β-lactamase (AmpC)-producing (2007: 0.8%, 2008: 3.2%, 2009: 2.7%) Escherichia coli in Canadian hospitals have fluctuated from 2007 to 2009. Rates of co-resistance to non-lactam agents are elevated, and multidrug-resistant (MDR) phenotype were observed among E. coli strains producing ESBLs (83.3% MDR) and AmpCs (31.0%). The majority (>98%) of isolates remained susceptible to colistin, tigecycline, amikacin, and the carbapenems. CMY-2 encoding gene was detected in 52.9% of AmpC-producing strains, while bla(CTX-M-15) (65.2%) was the predominant ESBL genotype. A total of 50.3% of ESBL-producing E. coli and 21.4% of AmpC producers belonged to the ST131 clone. In conclusion, ESBL- and AmpC-producing E. coli are established in Canadian hospitals; and although the prevalence rates of these isolates remain low, they are often MDR and associated with the ST131 clone.
authors.affiliation: Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada R3E 0J9. trishsimner@gmail.com
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Simner
authors.forename: George G
authors.initials: GG
authors.lastname: Zhanel
authors.forename: Johann
authors.initials: J
authors.lastname: Pitout
authors.forename: Franil
authors.initials: F
authors.lastname: Tailor
authors.forename: Melissa
authors.initials: M
authors.lastname: McCracken
authors.forename: Michael R
authors.initials: MR
authors.lastname: Mulvey
authors.forename: Philippe R S
authors.initials: PR
authors.lastname: Lagacé-Wiens
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Adam
authors.forename: Daryl J
authors.initials: DJ
authors.lastname: Hoban
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015373:Bacterial Typing Techniques; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D005838:Genotype; D006761:Hospitals; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058889:Molecular Typing; D016133:Polymerase Chain Reaction; D015995:Prevalence; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D001618:beta-Lactamases