Frequency of bacteriuria in dogs with chronic kidney disease: A retrospective study of 201 cases.

Background: Studies have shown an increased prevalence of positive urine culture (PUC) in cats with chronic kidney disease (CKD); no information is available in dogs. Objectives: To document the PUC frequency in a cohort of dogs with CKD, determine risk factors for PUC, and identify associations between clinicopathologic data and PUC. Animals: Two hundred one client-owned dogs with CKD. Methods: Retrospective, observational study. Dogs recruited from 2 veterinary teaching hospitals were included if they were diagnosed with CKD and had a culture performed on urine collected by cystocentesis. The PUC frequency was calculated, multivariate analysis was performed to identify risk factors, and associations with clinicopathologic data were investigated. Results: Sixty-five dogs (32%) with CKD had PUC, including 8 (28%) in International Renal Interest Society (IRIS) stage 1; only 8% showed signs of a urinary tract infection. Escherichia coli was the most common isolate (67%). A PUC was more likely in females (odds ratio [OR], 3.22; 95% confidence interval [CI], 1.67-6.37; P < .001) than males and in clogs with isosthenuria (OR, 2.48; 95% CI, 1.24-5.03; P = .01) than in dogs with urine-specific gravity 1.013-1.024. A positive leukocyte esterase test and microorganisms found by urine sediment analysis were significantly associated with PUC (both P < .001). Conclusions and Clinical Importance: Dogs with CKD, even IRIS stage 1, have a high frequency of PUC and most cases are asymptomatic. A urine culture could be considered in the routine evaluation of dogs with CKD, but the clinical relevance of a PUC remains unknown and needs further evaluation.