Serum-effusion albumin gradient in dogs with transudative abdominal effusion

A prospective clinical study in dogs with transudative abdominal effusions examined the clinical usefulness of the serum albumin-effusion albumin (SA- EA) gradient. In humans, the SA-EA gradient facilitates classification of a bdominal effusion, with a gradient greater than or equal to1.1 indicating t he presence of portal hypertension. Gradient values proved useful for predi cting therapeutic response to sodium restriction and diuresis in humans. Of 49 dogs evaluated, 25 had hepatobiliary disease (group 1) and 24 had other nonhepatobiliary conditions (group 2). Portal hypertension was clinically suspected in 24 of 25 dogs in group 1 and in 15 of 24 dogs in group 2. A br oad range of SA-EA gradients was found. A gradient greater than or equal to 1.1 was found in 22 of 25 (88.0%) dogs with liver disease and in 14 of 24 ( 58.3%) dogs with other disorders. The median SA-EA gradient was higher in g roup 1 than in group 2, with values of 1.4 (range, 0.7-3.1) and 1.1 (range, 0.3-2.6), respectively (P < .04). Considerable overlapping of SA-EA gradie nts occurred between groups and among dogs with diverse conditions such tha t gradient values could not distinguish dogs with hepatobiliary disease fro m dogs with other conditions. The overall diagnostic accuracy of the SA-EA gradient in predicting portal hypertension in dogs with and without hepatob iliary disease (69.4%) exceeded that of hypoalbuminemia (57.1%). These find ings suggest that portal hypertension is a predominant force in formation o f transudative abdominal effusion in dogs with hepatobiliary disease and in dogs with other disorders. Whether the SA-EA gradient can be used to guide therapeutic mobilization of effusion in dogs remains to be proved.