LAUSR

BACKGROUND Clinical guidelines recommend empiric fluoroquinolone therapy for urinary tract infection (UTI) only where local Escherichia coli resistance does not exceed 10%, however access to local susceptibility data is not uniform across Canada and it is not known which regions meet this threshold. Our objective was to collect susceptibility data from across Canada to evaluate regional trends of E. coli resistance to fluoroquinolones. METHODS Antibiogram data was collected retrospectively for the years 2015-2019 from the most local level within each province; typically, Regional Health Authorities (RHAs) or local health zones. Antibiogram data was collected from publicly available sources or by directly contacting RHAs or health zones.  Susceptibility data was aggregated into regional or population-level data. RESULTS Antibiograms were collected from 72 regions across 10 provinces. These included 1,949,515 E. coli isolates. Only 7 regions throughout Canada met the IDSA target of less than 10% resistance to consider empiric fluoroquinolone therapy at any point during the study period.  The data consistently shows that outpatient populations tend to have the highest susceptibility to fluoroquinolones, followed by inpatient populations, and finally long-term care patients. Rural populations also generally had higher susceptibility than urban. Nationally, the Atlantic provinces tended to show the highest susceptibility, especially toward the end of the study period. CONCLUSION Fluoroquinolone resistance in E. coli appears to be plateauing within Canada after a rapid increase in the past 20 years. However, fluoroquinolones are rarely appropriate first-line treatment options for UTI within Canada in the absence of factors eliminating other therapeutic options.