344Risk Factors for Infection with Escherichia coli among Long-Term Care Facility Residents with Gastrointestinal Tract Colonization with Fluoroquinolone-Resistant E. coli

Background. Infections due to fluoroquinolone-resistant Escherichia coli (FQREC) are preceded by gastrointestinal colonization, and are associated with significant morbidity and mortality. Although colonization with FQREC is common among residents of long-term care facilities (LTCFs), risk factors associated with subsequent development of clinical infections in this population remain unclear. The objective of this study was to determine risk factors for developing a clinical infection with E. coli in LTCF residents with FQREC gastrointestinal colonization. Methods. A case-control study was conducted from 2006 to 2008 at three LTCFs within an academic long-term care network. Residents initially colonized with FQREC were followed for 12 months after enrollment, or until discharge or death. Case patients were defined by the presence of a clinical infection with E. coli, while control patients were defined as those that did not develop a clinical infection with E. coli. A multivariable logistic regression model was developed to identify risk factors for clinical infection with E. coli in residents with baseline FQREC colonization. Results. Over the 3-year study period, 234 participants had baseline colonization with E. coli, of which 94 (40%) were colonized with FQREC. Among patients with baseline FQREC colonization, 11 (12%) developed clinical infections with E. coli during the study period. Of these, 10 (90%) were due to FQREC. The median time to infection was 131 days (interquartile range, 57-299), with the majority of cases being urinary tract infections (n = 10; 90%). On multivariable analysis, significant risk factors for developing a clinical infection with E. coli included the presence of a urinary catheter (OR 11.6; 95% CI 1.87-71.6, P = 0.008), diabetes mellitus (OR 6.63; 95% CI, 1.14-38.5, P = 0.035), and receipt of trimethoprim-sulfamethoxazole in the 30 days prior to initial sampling up to development of infection (OR 14.6; 95% CI 2.28-93.0, P = 0.005). Conclusion. Development of clinical infections with E. coli was relatively common among LTCF residents with baseline colonization with FQREC. Future studies should focus on interventions for timely removal of urinary catheters and judicious use of antibiotics in this vulnerable, medically complex population. Disclosures. All authors: No reported disclosures.