Pleural effusion as a complication of extrahepatic biliary tract rupture in a dog

Bile pleural effusion associated with traumatic rupture of the extrahepatic biliary tract and bile peritonitis in a dog is described. Pleural and abdominal fluids were identical cytologically and chemically despite a grossly intact diaphragm. Transfer of peritoneal fluid across the diaphragm via lymphatics and subsequent leakage into the pleural space is the likely cause of effusion. Pleural and abdominal fluid accumulation resolved spontaneously with repeated abdominocenteses and supportive care.