Diagnosis and Surgical Management of a Hemorrhagic Hepatic Pseudocyst in a Young British Shorthair Cat

Hemorrhagic hepatic pseudocysts are uncommon in cats and can present diagnostic and therapeutic challenges. This report describes the diagnosis and surgical management of a massive hemorrhagic hepatic pseudocyst in a 1-year-old intact male British Shorthair cat presented for castration with several days of intermittent vomiting. Physical examination revealed marked abdominal distension, while routine hematologic and biochemical testing showed no clinically significant abnormalities. Abdominal radiography revealed a large soft tissue opacity occupying most of the abdominal cavity. Ultrasonography identified a large fluid-filled cystic structure, and computed tomography confirmed a large hepatic cystic lesion with displacement of adjacent organs. Surgical exploration revealed a solitary hepatic cyst containing dark red hemorrhagic fluid. The cyst-fluid total bilirubin concentration was markedly higher than the serum concentration, although no gross communication with the biliary tract was identified during surgery. The lesion was completely excised while preserving the adjacent hepatic parenchyma. Histopathologic examination revealed a fibrous cyst wall with extensive hemorrhage and multifocal necrosis without an epithelial lining, supporting the diagnosis of a hemorrhagic hepatic pseudocyst. At 26 months after surgery, the owner reported that the cat had remained clinically well, and abdominal radiographs showed no evidence of a recurrent abdominal mass. This case highlights hemorrhagic hepatic pseudocyst as a differential diagnosis for large hepatic cystic lesions in cats and suggests that complete surgical excision may be a treatment option for a resectable hepatic pseudocyst.