Establishment of a reference interval for urinary albumin‐to‐creatinine ratio in dogs

BACKGROUND: Albuminuria is an important marker of renal damage and can precede proteinuria; thus, it can be a useful analyte in the early diagnosis of kidney diseases. Albuminuria has also been found in dogs with hypertension, inflammatory, infectious, and neoplastic diseases. OBJECTIVES: The aim of this study was to establish a reference interval (RI) for albuminuria in dogs. METHODS: One hundred sixty‐four clinically healthy dogs were enrolled in the study. Urinary albumin was determined by the immunoturbidimetric method, and albumin excretion was expressed as the urinary albumin‐to‐creatinine (UAC) ratio. The RI for UAC was established. RESULTS: After exclusions, 124 dogs from 32 breeds remained. The median UAC of the study population was 3.0 mg/g (range: 0‐48). The RI was defined as 0‐19 mg/g (with a 90% CI for the upper limit of 13‐28 mg/g). No significant difference was found between male and female dogs or between different age and body weight groups. The results of Sighthounds (n = 30) and Beagle dogs (n = 23) did not differ from the other breeds. CONCLUSION: The canine RI of UAC is similar but somewhat narrower than the human RI.