Evaluation of the Efficacy and Safety of High Dose Short Duration Enrofloxacin Treatment Regimen for Uncomplicated Urinary Tract Infections in Dogs

Background: Uncomplicated urinary tract infections (UTI) in dogs usually are treated with antimicrobial drugs for 10–14 days. Shorter duration antimicrobial regimens have been evaluated in human patients. Hypothesis: A high dose short duration (HDSD) enrofloxacin protocol administered to dogs with uncomplicated UTI will not be inferior to a 14-day treatment regimen with amoxicillin-clavulanic acid. Animals: Client-owned adult, otherwise healthy dogs with aerobic bacterial urine culture yielding 103 CFU/mL of bacteria after cystocentesis. Methods: Prospective, multicenter, controlled, randomized blinded clinical trial. Enrolled dogs were randomized to group 1 (enrofloxacin 18–20 mg/kg PO q24h for 3 days) or group 2 (amoxicillin-clavulanic acid 13.75–25 mg/kg PO q12h for 14 days). Urine cultures were obtained at days 0, 10, and 21. Microbiologic and clinical cure rates were evaluated 7 days after antimicrobial treatment was discontinued. Lower urinary tract signs and adverse events also were recorded. Results: There were 35 dogs in group 1 and 33 in group 2. The microbiologic cure rate was 77.1 and 81.2 % for groups 1 and 2, respectively. The clinical cure rate was 88.6 and 87.9 % for groups 1 and 2, respectively. Cure rates between groups did not differ according to the selected margin of noninferiority. Conclusions and Clinical Importance: HDSD enrofloxacin treatment was not inferior to a conventional amoxicillin-clavulanic acid protocol for the treatment of uncomplicated bacterial UTI in dogs. Further research is warranted to deter