title: Possible animal origin of human-associated, multidrug-resistant, uropathogenic Escherichia coli.
abstract: BACKGROUND
  The multistate occurrence of cases of urinary tract infection (UTI) caused by trimethoprim-sulfamethoxazole (TMP-SMZ)-resistant Escherichia coli strains belonging to a single clonal group (designated as clonal group A [CgA]) in the United States has raised an intriguing hypothesis that these infections may have been spread by contaminated food products. The present study attempted to determine if CgA strains could be traced to food animals.
  
  
  METHODS
  A total of 495 animal and environmental E. coli isolates, which belonged to serogroups O11, O17, O73, and O77 and were collected between 1965 and 2002 by the Gastroenteric Disease Center at Pennsylvania State University (University Park, PA), were further subtyped by antimicrobial drug susceptibility, enterobacterial repetitive intergenic consensus (ERIC2) PCR, random amplified polymorphic DNA analysis, pulsed-field gel electrophoresis (PFGE), and virulence profile pattern.
  
  
  RESULTS
  Of 495 isolates, 128 (26%) had an ERIC2 PCR electrophoretic pattern indistinguishable from that of the human prototype CgA strain, and 14 CgA isolates were resistant to TMP-SMZ. Cluster analysis of PFGE patterns showed that 1 of these 14 isolates, obtained from a cow in 1988, was 94% similar to a CgA uropathogenic human-associated E. coli strain. The pattern for this isolate was included among a cluster of PFGE patterns for 5 human-associated UTI isolates that were >80% similar to each other.
  
  
  CONCLUSIONS
  These observations suggest that drug-resistant, uropathogenic human-associated E. coli strains potentially have an animal origin. The possibility that human drug-resistant UTI could be a foodborne illness has serious public health implications.
authors.affiliation: Division of Infectious Diseases, School of Public Health, University of California, Berkeley, CA 94720, USA.
authors.forename: Meena
authors.initials: M
authors.lastname: Ramchandani
authors.forename: Amee R
authors.initials: AR
authors.lastname: Manges
authors.forename: Chitrita
authors.initials: C
authors.lastname: DebRoy
authors.forename: Sherry P
authors.initials: SP
authors.lastname: Smith
authors.forename: James R
authors.initials: JR
authors.lastname: Johnson
authors.forename: Lee W
authors.initials: LW
authors.lastname: Riley
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000382:microbiology; D005838:Genotype; D006801:Humans; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology; D014552:Urinary Tract Infections / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics; D015047:Zoonoses / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors; D015662:Trimethoprim, Sulfamethoxazole Drug Combination