Hepatic Papillomatosis in a middle-aged cat

Abstract

Background According to the authors’ knowledge biliary papillomatosis is a rare disease and has not yet been described in animals. Episodes of recurrent cholangitis and associated icterus have been associated with biliary papillomatosis and confirmation of diagnosis is via histopathology, where it is characterized by the proliferation of the columnar papillary epithelium of the bile ducts. This epithelium extends into the lumen, partially or completing obstructing it. Case presentation A 8-year-old neutered domestic short-hair cat was presented for evaluation of recurrent generalized muscle atrophy, abdominal distension and marked icterus. One year before presentation, the cat was diagnosed with chronic lymphocytic cholangitis associated with intrahepatic cholestasis. Treatment was initiated with prednisolone (Dermipred; Ceva) at 2mg/kg Per Os (PO) q24 for 2 weeks then reduced to 1mg/kg PO q24h and S-adenosylmethionine 20 mg/kg (Zentonil;Vetoquinol). On presentation, the cat had marked icterus and abdominal distension. Results of abdominal ultrasound revealed large fluid lesions on hepatic parenchyma with marked dilated bile ducts. An exploratory laparotomy was performed and cystic structures were identified on the right lateral and on central division of the liver. Cholecystectomy and hepatic lobectomies with omentalization at the base of the cystic structures were performed. Histopathological analysis revealed the presence of benign papillomatosis. The cat was re-examined 2 weeks after surgery at which point clinical examination was normal. Four months after surgical intervention, the cat had recurrent clinical signs, and abdominal ultrasound revealed the presence of a large volume abdominal effusion and diffuse cystic changes within the rest of the liver. At this stage the owners elected for euthanasia. Conclusion To our knowledge, this is the first description of papillomatosis in animals. The final diagnosis was biliary papillomatosis which has never been reported in cats. The diagnosis can be difficult and it’s also a rare condition in human medicine. Biliary papillomatosis should be included in the differential diagnosis of hepatic cystic-like lesions in cats.