Evaluation of urine dipstick for proteinuria assessment in pet rabbits

BACKGROUND: Naturally occurring kidney disease (KD) in pet rabbits has not been fully characterized. It has been previously suggested that proteinuria, especially when associated with isosthenuria, may be an early indicator of KD prior to azotaemia in rabbits. The aim of the current study was to assess the diagnostic utility of the urinary protein dipstick test (UPDT) for detecting proteinuria in rabbit urine samples as a useful diagnostic tool in clinical setting. METHODS: Three hundred urinalyses from 156 pet rabbits were retrospectively analysed by comparing the UPDT with the urine protein:creatinine ratio (UPC) to assess its diagnostic performance in detecting proteinuria, defined as UPC > 0.3. Sensitivity, specificity, positive and negative predictive values (NPVs) were determined. RESULTS: When urine-specific gravity (USG) was ≤1.024 and a UPDT result of >0 was considered proteinuric, the specificity and positive predictive value (PPV) were both 100%. Following the same criteria, specificity and PPV decreased to 92.1% and 92.5% when USG was ≤1.038. NPVs were poor. CONCLUSION: In rabbits, a UPDT result > 0 is indicative of proteinuria (UPC > 0.3) when the USG is ≤1.024. In all other cases, proteinuria should be measured using the UPC.