Extrahepatic biliary atresia is a common cause of cholestasis in children but is rare in animals. It can involve any portion of the biliary tree, including the hepatic, cystic, or common bile duct. The cause of the malformation is unknown, but early surgical intervention is critical. If left untreated, cholestasis, recurrent cholangitis, portal hypertension, and hepatic cirrhosis can develop. Imaging of the biliary tree by ultrasound or direct contrast cholangiogram may help identify this condition.
This case report details the clinical, imaging, and surgical features of a 4-week-old pug with extrahepatic biliary atresia. The puppy presented with lethargy and poor weight gain despite a good appetite. CBC and serum chemistry panel analysis revealed neutrophilic leukocytosis and elevations in bilirubin, alkaline phosphatase, alanine aminotransferase, and glutamate dehydrogenase. A biliary drainage problem was suspected based on the presence of acholic feces, elevated ammonia, and dilation of the gallbladder and bile duct on ultrasonography. There was no ultrasonographic evidence of a portosystemic shunt, and the major duodenal papilla could not be identified. Exploratory laparotomy revealed absence of the major duodenal papilla that allows entrance of the common bile duct into the intestines. A cholecystoduodenostomy was performed. Feces color was normal the day after surgery. Postoperative ultrasounds over 6 months showed that the stoma remained functional, maintaining a small gallbladder. At 15 months postoperatively, the dog’s ammonia level and clinical function were normal, although bile acid concentrations remained quite elevated.