CT features and short-term outcome in cats presenting with pyothorax

ObjectivesThe purpose of this retrospective, descriptive study was to assess CT findings and short-term outcome of cats with pyothorax presented to a referral hospital.MethodsThoracic CT studies of 41 cats with pyothorax comprising pre-contrast lung and soft tissue reconstructions and post-contrast soft tissue reconstructions were blindly reviewed by two European College of Veterinary Diagnostic Imaging (ECVDI) board-certified radiologists and a third-year ECVDI resident, referencing a predetermined list of imaging features. Clinical outcomes, including treatment options, survival to discharge and length of hospitalisation, were recorded.ResultsAll cats (100%) had pleural effusion. Common imaging findings included intrathoracic lymphadenomegaly (85%), pleural thickening (85%), presence of pannus (81%) and evidence of pneumonia (49%). Pulmonary abscessation was suspected in 22% of cats and foreign bodies in 12%. Of the 41 cats, 20 were managed medically, 20 underwent surgery and one had unsuccessful medical treatment followed by surgical intervention. The median duration of hospitalisation was 7 days, and 36 cats survived to discharge.Conclusions and relevanceThis study demonstrates that cats with pyothorax commonly have marked changes on CT that involve multiple thoracic compartments. Our study population highlights that feline pyothorax can have a good short-term outcome when managed either medically or surgically.