title: Characterization of extended-spectrum beta-lactamases produced by Escherichia coli isolated from hospitalized and nonhospitalized patients: emergence of CTX-M-15-producing strains causing urinary tract infections.
abstract: Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates were obtained from hospitalized and nonhospitalized patients in Belgium between August 2006 and November 2007. The antimicrobial susceptibility of these isolates was determined and their ESBL genes were characterized. Clonal relationships between the CTX-M-producing E. coli isolates causing urinary tract infections were also studied. A total of 90 hospital- and 45 community-acquired cephalosporin-resistant E. coli isolates were obtained. Tetracycline, enrofloxacine, gentamicin, and trimethoprim-sulfamethaxozole resistance rates were significantly different between the community-onset and hospital-acquired isolates. A high diversity of different ESBLs was observed among the hospital-acquired E. coli isolates, whereas CTX-M-15 was dominating among the community-acquired E. coli isolates (n = 28). Thirteen different pulsed-field gel electrophoresis profiles were observed in the community-acquired CTX-M-15-producing E. coli, indicating that multiple clones have acquired the bla(CTX-M-15) gene. All community-acquired CTX-M-15-producing E. coli isolates of phylogroups B2 and D were assigned to the sequence type ST131. The hospital-acquired CTX-M-15-producing E. coli isolates of phylogroups B2, B1, A, and D corresponded to ST131, ST617, ST48, and ST405, respectively. In conclusion, CTX-M-type ESBLs have emerged as the predominant class of ESBLs produced by E. coli isolates in the hospital and community in Belgium. Of particular concern is the predominant presence of the CTX-M-15 enzyme in ST131 community-acquired E. coli.
authors.affiliation: Department of Pathology, Bacteriology, and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium. annemieke.smet@ugent.be
authors.forename: Annemieke
authors.initials: A
authors.lastname: Smet
authors.forename: An
authors.initials: A
authors.lastname: Martel
authors.forename: Davy
authors.initials: D
authors.lastname: Persoons
authors.forename: Jeroen
authors.initials: J
authors.lastname: Dewulf
authors.forename: Marc
authors.initials: M
authors.lastname: Heyndrickx
authors.forename: Geert
authors.initials: G
authors.lastname: Claeys
authors.forename: Marc
authors.initials: M
authors.lastname: Lontie
authors.forename: Britt
authors.initials: B
authors.lastname: Van Meensel
authors.forename: Lieve
authors.initials: L
authors.lastname: Herman
authors.forename: Freddy
authors.initials: F
authors.lastname: Haesebrouck
authors.forename: Patrick
authors.initials: P
authors.lastname: Butaye
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001530:Belgium / Q000453:epidemiology; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D016133:Polymerase Chain Reaction; D014552:Urinary Tract Infections / Q000453:epidemiology* / Q000382:microbiology; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; C473109:beta-lactamase CTX-M-15; D001618:beta-Lactamases