Resistance of Escherichia coli urinary isolates in ED-treated patients from a community hospital.

PURPOSE: The purpose of this study is to provide resistance data for Escherichia coli isolates causing urinary tract infections in emergency department (ED) patients not requiring admission and explore if differences between this subpopulation and the hospital antibiogram exist. Differences between community-acquired urinary tract infection (CA-UTI) and health care-associated (HA-UTI) subgroups were also investigated.

METHODS: Patients with a positive urine culture treated and discharged from the ED of a 200-bed community hospital were reviewed. Patients with urinary isolates of more than 100000 colony-forming unit/mL and documented intention to treat were included. Patients who required admission, were pregnant, less than the age of 18 years, or who had a positive culture but without any evidence of intention to treat were excluded. Only the initial visit was included for patients who returned to the ED within 7 days.

RESULTS: Overall, 308 visits were screened, and 217 were included. Of these, 78.3% were CA-UTI, and 21.7% were HA-UTI. Females comprised 88.5% of all patients. E coli was the most common pathogen overall and in both subgroups. E coli resistance to levofloxacin was 13.5% overall, 9.2% for CA-UTI, and 38.5% for HA-UTI compared with 27% on the hospital antibiogram. E coli resistance to sulfamethoxazole/trimethoprim was 26.9% overall, 25.2% for CA-UTI, and 34.6% for HA-UTI vs 26% on the antibiogram.

CONCLUSIONS: E coli susceptibility for ED patients not requiring admission may not be accurately represented by hospital antibiograms that contain culture data from various patient types, sites of infection, or patients with varying illness severity. Separation of the ED population into CA-UTI and HA-UTI subgroups may be helpful when selecting empiric antibiotic therapy.