title: Molecular epidemiology of CTX-M-producing Escherichia coli isolates at a tertiary medical center in western Pennsylvania.
abstract: A combination of phenotypic and genotypic methods was used to investigate 70 unique Escherichia coli clinical isolates identified as producing extended-spectrum beta-lactamases (ESBLs) at a medical center in Pittsburgh, PA, between 2007 and 2008. Fifty-seven isolates (81%) produced CTX-M-type ESBLs, among which CTX-M-15 was predominant (n = 46). Isolates producing CTX-M-2, -9, -14, and -65 were also identified. One CTX-M-producing isolate coproduced CMY-2 cephalosporinase. Ten isolates (14%) produced SHV-type ESBLs, either SHV-5 or SHV-7. Two isolates produced only CMY-2 or -32. Pulsed-field gel electrophoresis revealed the presence of two major clusters of CTX-M-15-producing E. coli isolates, one in phylotype B2 (n = 15) and the other in phylotype A (n = 19). Of four phylotype B2 isolates that were able to transfer the bla(CTX-M-15)-carrying plasmids, three showed fingerprints related (>60%) to those of plasmids from phylotype A isolates. In phylotype B2, all CTX-M-15-producing isolates, as well as three isolates producing CTX-M-14, two producing SHV-5, and one producing SHV-7, belonged to the international epidemic clone defined by serotype O25:H4 and sequence type 131. The plasmids from eight of nine CTX-M-15-producing E. coli isolates of phylotype A that were examined were highly related to each other and were also found in two isolates belonging to phylotype D, suggesting horizontal transfer of this bla(CTX-M-15)-carrying plasmid between phylotypes. Our findings underscore the need to further investigate the epidemiology and virulence of CTX-M-producing E. coli in the United States.
authors.affiliation: Division of Infectious Diseases, University of Pittsburgh Medical Center, 3550 Terrace Street, Pittsburgh, PA 15261, USA.
authors.forename: Hanna E
authors.initials: HE
authors.lastname: Sidjabat
authors.forename: David L
authors.initials: DL
authors.lastname: Paterson
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Adams-Haduch
authors.forename: Lindsay
authors.initials: L
authors.lastname: Ewan
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Pasculle
authors.forename: Carlene A
authors.initials: CA
authors.lastname: Muto
authors.forename: Guo-Bao
authors.initials: GB
authors.lastname: Tian
authors.forename: Yohei
authors.initials: Y
authors.lastname: Doi
mesh_terms: D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D004927:Escherichia coli Infections / Q000382:microbiology*; D022761:Gene Transfer, Horizontal; D006801:Humans; D008826:Microbial Sensitivity Tests; D010957:Plasmids; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: C473109:beta-lactamase CTX-M-15; D001618:beta-Lactamases
references.citation: J Clin Microbiol. 2008 Jan;46(1):103-8
references.pmid: 17959756
references.citation: Curr Opin Microbiol. 2006 Oct;9(5):466-75
references.pmid: 16942899
references.citation: Antimicrob Agents Chemother. 2007 Nov;51(11):4015-21
references.pmid: 17724160
references.citation: Antimicrob Agents Chemother. 2000 Jul;44(7):1970-3
references.pmid: 10858363
references.citation: J Antimicrob Chemother. 2007 Feb;59(2):165-74
references.pmid: 17158117
references.citation: J Antimicrob Chemother. 2008 Feb;61(2):273-81
references.pmid: 18077311
references.citation: Emerg Infect Dis. 2007 Jul;13(7):1121-3
references.pmid: 18214201
references.citation: Emerg Infect Dis. 2008 Feb;14(2):195-200
references.pmid: 18258110
references.citation: J Antimicrob Chemother. 2008 Dec;62(6):1241-4
references.pmid: 18779256
references.citation: J Antimicrob Chemother. 2002 Jul;50(1):11-8
references.pmid: 12096001
references.citation: J Antimicrob Chemother. 2006 Sep;58(3):665-8
references.pmid: 16870648
references.citation: J Clin Microbiol. 2009 Feb;47(2):358-61
references.pmid: 19109470
references.citation: Microb Drug Resist. 2008 Sep;14(3):211-6
references.pmid: 18707552
references.citation: J Clin Microbiol. 2005 Dec;43(12):5860-4
references.pmid: 16333067
references.citation: Am J Infect Control. 2006 Jun;34(5 Suppl 1):S20-8; discussion S64-73
references.pmid: 16813978
references.citation: J Clin Microbiol. 2009 Sep;47(9):2970-4
references.pmid: 19587301
references.citation: Antimicrob Agents Chemother. 2004 Jan;48(1):1-14
references.pmid: 14693512
references.citation: Am J Infect Control. 2007 Nov;35(9):606-12
references.pmid: 17980240
references.citation: J Antimicrob Chemother. 2008 May;61(5):1024-8
references.pmid: 18334490
references.citation: Antimicrob Agents Chemother. 2006 Nov;50(11):3953-5
references.pmid: 16954321
references.citation: J Antimicrob Chemother. 2009 Jan;63(1):72-9
references.pmid: 19004839
references.citation: J Antimicrob Chemother. 2008 Jun;61(6):1393-4
references.pmid: 18356153
references.citation: Antimicrob Agents Chemother. 2008 May;52(5):1790-3
references.pmid: 18347108
references.citation: Int J Antimicrob Agents. 2007 May;29(5):598-600
references.pmid: 17234386
references.citation: Antimicrob Agents Chemother. 2003 Dec;47(12):3724-32
references.pmid: 14638473
references.citation: J Clin Microbiol. 2005 Jun;43(6):2844-9
references.pmid: 15956407
references.citation: Antimicrob Agents Chemother. 2004 Oct;48(10):3758-64
references.pmid: 15388431
references.citation: J Antimicrob Chemother. 2005 Nov;56(5):819-26
references.pmid: 16188915
references.citation: Antimicrob Agents Chemother. 2003 Jul;47(7):2382-3
references.pmid: 12821506
references.citation: Clin Infect Dis. 2009 Mar 15;48(6):739-44
references.pmid: 19187027
references.citation: Appl Environ Microbiol. 2000 Oct;66(10):4555-8
references.pmid: 11010916
references.citation: Foodborne Pathog Dis. 2006 Spring;3(1):59-67
references.pmid: 16602980
references.citation: J Antimicrob Chemother. 2008 Aug;62(2):284-8
references.pmid: 18453527
references.citation: J Clin Microbiol. 2008 Dec;46(12):3900-5
references.pmid: 18842941
references.citation: FEMS Microbiol Lett. 2001 Jul 24;201(2):237-41
references.pmid: 11470367
references.citation: J Antimicrob Chemother. 2002 Dec;50(6):1031-4
references.pmid: 12461028