[Congenital bile duct cysts and liver fibrosis in a foal]

A three-week-old foal was submitted to the clinic because of a minor traumatic injury at the lower jaw. At admission the foal exhibited diarrhea, a distended abdomen and reduced general condition. These findings could not be associated with the injury. On abdominal radiography decreased abdominal detail and a dorsocaudal displacement of the intestine was present. Ultrasonographically multiple fluid-filled cystic structures of several centimeters in diameter were identified. These cystic structures appeared to be associated with the liver. At laparotomy and at necropsy the liver was markedly enlarged and firm and had large, thin-walled, with a bile-like fluid filled cysts, 4-20 centimeters in diameter. Histological lesions were characterized by proliferation of small bile ducts and of interlobular connective tissue as well as focal subacute cholangitis. Gross and histological findings were considered to be consistent with congenital polycystic liver disease and fibrosis with ascending cholangitis.