Biliothorax in a Siamese Cat

A 2-year-old male neutered cat presented for further investigation of biliothorax. The cat was initially treated for pyothorax, including bilateral chest drains for lavage of the pleural space. Five days later, the pleural effusion turned clear-yellow and had a bilirubin concentration of 427 μmol/l compared to the serum bilirubin concentration of 15 μmol/l. Exploratory surgery revealed a 2mm tear in the diaphragm, with a corresponding 2mm defect in the diaphragmatic surface of the gall bladder, creating a fistula between the gall bladder and the pleural cavity. The defects were repaired routinely and the cat made a full recovery. It was suspected that the tears had been created at the time of the thoracostomy tube placement. Biliothorax has not been described before in a cat, and appears to be a rare complication following thoracostomy tube placement.