Stratification by demographic and clinical data of the antibiotic susceptibility of Escherichia coli from urinary tract infections of the community

AIM: To determine the patterns of antibiotic susceptibility of Escherichia coli strains isolated from adult patients with urinary tract infection (UTI), and to stratify the results by age and type of UTI to verify if there are statistically significant differences that can help physicians to prescribe better empirical antibiotherapy. DESIGN: Cross-sectional prospective study. LOCATION: Community of Getafe (Madrid). Primary care level. PARTICIPANTS: 100 E. coli strains, randomly chosen, isolated from the urine (10(4)–10(5) cfu/ml) of different patients from primary care centers in the Getafe area. MAIN MEASUREMENTS: The antibiotic susceptibility of the strains was evaluated and the results were stratified by age and type of UTI. The clinical and demographic data of the patients were analyzed, classifying each episode as complicated UTI or uncomplicated UTI. RESULTS: Strains isolated from patients with uncomplicated UTI showed significantly greater susceptibility than those of complicated UTI to amoxicillin (65.9% vs. 30.6%, p = 0.001), amoxicillin/clavulanic acid (95.5% vs. 77.6%, p = 0.013) and ciprofloxacin (81.8% vs. 63.3%, p = 0.047). In complicated UTI, susceptibility to ciprofloxacin was significantly greater in the ≤65 years age group compared to the older age group (78.3% vs. 50%, respectively, p = 0.041). In the rest of antibiotics, no statistically significant differences were obtained when comparing by age (≤65 years versus >65 years), both in uncomplicated and complicated UTI. CONCLUSIONS: Clinical and demographic data of patients with UTI are of great importance in the results of the antibiotic susceptibility in E. coli. Antibiograms stratified by patient characteristics may better facilitate empirical antibiotic selection for UTI in primary care.