Epidemiology of an uropathogenic E coli clonal group

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DESCRIPTION (provided by applicant): This is a pilot project that aims to characterize the epidemiology of a recently identified clonal group of uropathogenic Escherichia coli designated as CgA. CgA refers to a set of multidrug-resistant E. coli strains that have identical ERIC PCR patterns and identical or similar pulsed field gel electrophoresis (PFGE) patterns, that belong to serotypes O11:nt and O77:nt, and that share identical or similar virulence factor profiles. In a multicenter study, we discovered that CgA accounted for a substantial proportion of community-acquired drug-resistant urinary tract infections (UTI) in 3 distinct university communities in the United States. The widespread dissemination of CgA raised the possibility that this clonal group of E. coli may be spread by contaminated ingestible vehicles. We hypothesize that the increase in prevalence of drug-resistant UTI in a community is affected not only by the frequency in the use of antimicrobial agents, but also by the introduction into such communities of clonal groups of drug-resistant uropathogenic E. coli by contaminated vehicles. In this application, we wish to: (1) identify the geographic distribution of CgA and the clinical spectrum of infections caused by this organism, including complications of UTI; and (2) reservoir and risk factors for infection with CgA. The geographic distribution of CgA will be studied by the analyses of E. coli archives obtained by the PI from northern California, Brazil, and New York, and by the collaborator (Dr. James Johnson) from Minnesota, Iowa, Washington, and a WHO Reference Laboratory. The incidence and prevalence of complications of UTI (pyelonephritis and bacteremia) caused by CgA will be determined by the analyses of E. coli isolates obtained from patients in a San Francisco hospital in collaboration with Dr. Francoise Perdreau-Remington. The possible animal reservoir for CgA will be examined by the analysis of all available O11:nt and O77:nt E. coli isolates from animals in collaboration with Dr. Chobi DebRoy. Through this pilot study, we wish to provide preliminary evidence in support of the hypothesis that drug-resistant uropathogenic E. coli can be spread by contaminated ingestible vehicles, and use the data generated from this project to design long-term studies to better characterize risk factors associated with CgA infection.