Objective: The aims of this prospective clinical cohort study were to determine the prevalence of asymptomatic bacteriuria in dogs with cranial cruciate ligament disease and to determine which clinical parameters and clinicopathologic data are associated with asymptomatic bacteriuria. Another aim was to determine the incidence of surgical site infections in dogs with and without asymptomatic bacteriuria.

Results: In 156 dogs with cruciate ligament disease, the prevalence of asymptomatic bacteriuria was 7.1%. Furthermore, the prevalence was 12.4% in female dogs and 0% in male dogs. The most common bacterial isolate was Escherichia coli. Patient sex, urine white blood cells/ high-powered field, and microscopic bacteriuria were significantly different between dogs with and without asymptomatic bacteriuria. Only 60% of dogs with microscopic bacteriuria had growth on urine aerobic culture. No significant difference was found in age, body weight, body condition score, duration of lameness, limb affected, or other urinalysis values between dogs with and without asymptomatic bacteriuria. Of the dogs that had 8-week repeat cultures, 2/3 dogs with asymptomatic bacteriuria had negative urine cultures and 3/43 without asymptomatic bacteriuria had positive urine cultures. Of 57 dogs that received surgery and had sufficient follow-up, 15 developed surgical site infection. All surgical site infections occurred in dogs without AB. The incidence of surgical site infection in this population was 26.3% (15/57).

Conclusions: Prevalence of asymptomatic bacteriuria in dogs presenting with cranial cruciate ligament disease was similar to previously reported values in male and female dogs. This suggests that dogs with cranial cruciate ligament disease are not more prone to asymptomatic bacteriuria than dogs in previously studied populations. Preliminary data suggests that AB does not predispose dogs to SSI however further research and continued data collection is warranted.