Risk factors for enterococcal bacteriuria in dogs: A retrospective study

Abstract

Background: In humans, Enterococcus spp. urinary tract infections (UTI) are commonly associated with urinary catheter-induced urothelial inflammation but this is not the case in dogs. Hypothesis/Objectives: To identify risk factors predisposing dogs to enterococcal bacteriuria. Animals: Seventy dogs with Enterococcus spp. bacteriuria (case) and 70 dogs with Enterococcus coli bacteriuria (control). Methods: A single center retrospective case-control study with subjects and controls identified by a medical records search for Enterococcus spp. (subject) or E coli (control) bacteriuria from January 1, 2014 to December 31, 2017. Cases and controls were balanced with respect to average age and weight. Binary logistic regression was used to estimate and test whether the odds of having Enterococcus spp. bacteriuria (instead of E coli) were associated with the presence of any given characteristic. Results: A history of recurrent bacteriuria was significantly more common in Enterococcus spp. cases than in E coli controls (odds ratio [OR]: 2.07; 95% confidence interval [CI]: 1.04-4.16, P =.04). Comorbidities associated with the presence of Enterococcus spp. bacteriuria included lower urinary tract (LUT) anatomic abnormalities (OR: 2.94; 95% CI: 1.17-8.10, P =.02), urolithiasis (P =.01), and the presence of LUT neoplasia (P =.04). Small frequencies (n = 12 and n = 6, respectively) compromise our ability to precisely estimate the genuine OR for the latter 2 characteristics. Conclusions and Clinical Importance: If the identified risk factors promote Enterococcus spp. colonization in dogs via induced LUT inflammation similar to people then Enterococcus spp. bacteriuria could be a sentinel for underlying LUT inflammation.