Evaluation of the bromosulfophthalein 30-minute retention test for the diagnosis of hepatic disease in dogs

The purpose of this study was to evaluate efficacy of bromosulfophthalein ( BSP) retention testing in dogs with and without histopathologically confirm ed hepatobiliary disease. Medical records of 150 dogs with hepatobiliary di sease having both a BSP test and hepatic biopsy were retrieved. Histopathol ogic slides of liver tissue were reviewed, and dogs were classified accordi ng to 1 of 11 histopathologic categories. Twenty-five clinically normal ran dom-source dogs were used as controls for hepatic biopsy and BSP testing. N o dogs suffered adverse effects due to BSP administration. BSP retention wa s significantly (P < .05) higher in hospitalized (13.9%) than control (3.2% ) dogs, but the test could not distinguish between hospitalized dogs with d ifferent types of hepatobiliary disease. Sensitivity, specificity, and pred ictive values of BSP retention as a test for hepatic disease were calculate d. Using 5.0% as a cutoff for normal BSP retention resulted in a specificit y of 88% and a sensitivity of 76%. Using 6.0% as a cutoff for normal BSP re tention resulted in a specificity of 100% and a sensitivity of 70%. Dogs of this study having BSP retention of >6% had at least an 86% chance of havin g an abnormal liver. We concluded that continued use of BSP retention testi ng is warranted as a noninvasive diagnostic test for liver disease in dogs.