Spontaneous gall bladder infarction in a dog with a congenital extrahepatic portosystemic shunt

A two-year-old entire female miniature dachshund was referred with a 10-day-history of polyuria, polydipsia, vomiting and inappetence and she was diagnosed with a left gastro-azygos portosystemic shunt. The dog underwent surgical attenuation of the shunt with a 5 mm ameroid ring constrictor and recovered uneventfully from the procedure. Two days after surgery, the dog developed acute abdominal pain. Abdominal ultrasonography revealed free peritoneal effusion and analysis of the fluid was consistent with biliary effusion. Diagnosis of biliary peritonitis was therefore made. On exploratory coeliotomy an evident leak of bile from the extrahepatic biliary tree was not detected. However, the gall bladder appeared macroscopically abnormal and a cholecystectomy was performed. Histopathological examination revealed gall bladder infarction characterised by intravascular fibrin thrombi and transmural coagulative necrosis. There was no overt inflammation and the bile was aseptic. The dog recovered uneventfully and was discharged from the hospital 10 days after surgery.