This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Google Scholar
Right arrow Articles by Sidjabat, H. E.
Right arrow Articles by Doi, Y.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sidjabat, H. E.
Right arrow Articles by Doi, Y.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, November 2009, p. 4733-4739, Vol. 53, No. 11
0066-4804/09/$08.00+0     doi:10.1128/AAC.00533-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Molecular Epidemiology of CTX-M-Producing Escherichia coli Isolates at a Tertiary Medical Center in Western Pennsylvania{triangledown}

Hanna E. Sidjabat,1 David L. Paterson,1,2 Jennifer M. Adams-Haduch,1 Lindsay Ewan,1 Anthony W. Pasculle,1,3 Carlene A. Muto,1,4 Guo-Bao Tian,1,5 and Yohei Doi1*

Division of Infectious Diseases,1 Clinical Microbiology Laboratory,3 Department of Infection Control, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania,4 University of Queensland UQ Centre for Clinical Research and Royal Brisbane and Women's Hospital, Brisbane, Australia,2 Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, School of Life Science, Sichuan University, Chengdu, China5

Received 22 April 2009/ Returned for modification 29 May 2009/ Accepted 25 July 2009

A combination of phenotypic and genotypic methods was used to investigate 70 unique Escherichia coli clinical isolates identified as producing extended-spectrum β-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 blaCTX-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 blaCTX-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.

* Corresponding author. Mailing address: Division of Infectious Diseases, University of Pittsburgh Medical Center, Scaife Hall S829, 3550 Terrace Street, Pittsburgh, PA 15261. Phone: (412) 648-9445. Fax: (412) 648-8521. E-mail: yod4{at}pitt.edu

{triangledown} Published ahead of print on 17 August 2009.

Antimicrobial Agents and Chemotherapy, November 2009, p. 4733-4739, Vol. 53, No. 11
0066-4804/09/$08.00+0     doi:10.1128/AAC.00533-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»