Community - Associated Extended-spectrum Beta-lactamases (ESBL)
Community - Associated Extended-spectrum Beta-lactamases (ESBL)
The purpose of this study is to review patients with E. coli infections at the University of
 Pittsburgh Medical Center (UPMC) from September 1, 2006 to August 31, 2007 to determine if
 these infections have arisen in the community rather than in hospitals or nursing homes. The
 occurrence of such resistant isolates could be devastating if they were associated with
 bloodstream infection, such as sometimes accompanies a urinary tract infection, since
 antibiotic resistant E. coli is not suspected in isolates coming from the community.
 Therefore, the aims of this study are to:

 1. Review whether extended-spectrum beta-lactamase (ESBL)-producing organisms (E. coli,
 Klebsiella species and Proteus species) are hospital-acquired, healthcare-associated, or
 community-associated.

 2. Investigate the prevalence of ESBL-positive E. coli in foodstuffs (beef, poultry,
 turkey, and pork), as a potential source for ESBL producers in the community.

 3. Compare the clonal relationship of the genome and resistance plasmids carried by the
 ESBL-producing isolates (healthcare-associated, community-associated, and of animal
 origin) and study the associations of ESBL-mediated resistance with resistance to other
 classes of antimicrobials.
The following variables will be followed: age, sex, occupation, hospital location at the time
 of positive culture (ER, medical ward, ICU, etc.), prior hospitalization or nursing home
 admission, receipt of outpatient dialysis, home care or other regular medical care (eg,
 outpatient chemotherapy), presence of invasive devices, receipt of antibiotics, including
 their type and whether they were adequate for the resistance profile of the organism, and
 prior positive microbiologic cultures. All sites are collecting the following information
 that was collected as part of the patient's clinical treatment. The following variables will
 be collected at all sites: time and location of positive cultures, underlying diseases and
 severity of illness, presence of urinary or intravascular devices, recent immunomodulative
 therapies or radiation therapy, physical exam findings, laboratory and radiographical data,
 antimicrobial usage within 30 days of onset of the infection, microbiological data and
 resistance patterns, choice of antibiotics once the organism is identified, bacteriological
 outcomes, laboratory results, demographic information, medications, clinical outcome, gender,
 height, weight, ethnicity, and past medical history. We will collect information
 prospectively for one year. The bacteria in the patient's cultures will be subcultured (after
 the diagnosis has been obtained since the microbiology lab would otherwise destroy the
 culture) and provided to the honest broker who will de-identify the specimen and link it to
 the medical information collected (which will also be de-identified by the honest broker).
 The following evaluation will be performed on these samples. The minimal inhibitory
 concentration of the antibiotic used in treatment will be performed by the E-Test method (AB
 Biodisk, Solna, Sweden). Specific mechanisms of antimicrobial resistance will be studied with
 emphasis on the presence of beta-lactamases produced by the bacteria. This evaluation will be
 performed by analytical isoelectric focusing techniques as well as PCR and gene sequencing
 analysis to determine genes encoding beta-lactamases. Biologic samples will be under the
 control of the principal investigator of this research project. All samples provided to the
 investigators are de-identified by the honest broker and will be coded with numbers. The
 information linking these code numbers to the corresponding subjects' identities will be kept
 in a separate, secure location that only the honest broker has access to. The investigators
 on this study will keep the samples indefinitely. Samples will be kept in the investigator's
 laboratory located in Scaife Hall, room 812, 3500 Terrace Street. At no time will the
 research investigators have access to any patient identifiers. Medical record information and
 bacteria samples from facilities outside of UPMC will be provided to the PI de-identified. At
 no time will anyone on the research team have access to patient identifiers. All information
 and bacteria are collected as part of the patient's clinical treatment.
Inclusion Criteria:

 -  All patients with E. coli, Klebsiella species, and Proteus species infections during
 the time period of the study will be reviewed. A community-associated E. coli isolate
 will be defined as one which was recovered from a clinical culture from a patient at
 UPMC who had no established risk factors for infection with an antibiotic resistant
 organism. Established risk factors are defined as:

 -  Isolation of the organism two or more days after admission for hospitalization OR

 -  History of hospitalization, surgery, dialysis, or residence in a long-term care
 facility within one year before the culture date OR

 -  The presence of an indwelling catheter or percutaneous medical device (eg,
 tracheostomy tube, gastrostomy tube, or Foley catheter) at the time of the
 culture OR

 -  Previous isolation of an antibiotic resistant organism.

 Exclusion Criteria:

 -  None