Comparison of antibiotic susceptibility of<i>Escherichia coli</i>in urinary isolates from an emergency department with other institutional susceptibility data

Abstract

PURPOSE: The antibiotic susceptibility of Escherichia coli in isolates from patients with uncomplicated urinary tract infection (UTI) in an emergency department (ED) was compared with susceptibility data from the associated hospital. METHODS: Patients eligible for study participation included women age 18-65 years with one or more symptoms consistent with a UTI for whom a urine dipstick, urinalysis, or urine culture was ordered. Clinical decision-making, including the decision to order a urine culture, was at the discretion of the individual healthcare provider; however, a deidentified urine culture and antimicrobial susceptibility testing were performed for those study participants for whom a urine culture was not ordered. We compared the E. coli-specific antibiogram for uncomplicated UTI to the antibiogram based on all urine cultures in the ED regardless of patient disposition, non-intensive care unit (ICU) hospital inpatients, and the hospitalwide antibiogram. RESULTS: Of the 578 ED patients screened for study eligibility, 119 met the inclusion criteria. E. coli, detected in 53 (74%) of the 72 pathogen-positive cultures, was the most common pathogen isolated. For E. coli, ciprofloxacin nonsusceptibility was significantly less common in isolates from ED patients with uncomplicated cystitis and pyelonephritis than in isolates from non-ICU inpatients or from the hospitalwide population. E. coli nonsusceptibility to ciprofloxacin was significantly less common in ED isolates from patients with uncomplicated UTI than in isolates from all ED patients with clinician-ordered urine cultures. CONCLUSION: Antibiotic susceptibility of E. coli in an ED and its associated hospital depended on factors such as whether patients were hospitalized and whether ED isolates were from patients with uncomplicated UTI.