Fungal Empyema Thoracis Associated with Clavispora lusitaniae—First Report in a Domestic Cat

Invasive fungal infections are life-threatening conditions that always pose a challenge to veterinary practitioners. The diagnostic and therapeutic approaches in a case of pleural effusion in a domestic cat with a 7-day history of progressive tachypnea were described. Fungal pyothorax was diagnosed on the basis of the clinical signs, radiography findings, complete blood counts, and isolation of the pathogen from pleural effusion samples on two occasions. After three thoracenteses for evacuation of the pleural exudate and 15-day therapy with terbinafine, the general condition of the patient was very good; the complete blood count and respiratory and heart rates returned to normal; and no diagnostic imaging signs of pleural effusion were present. To the best of our knowledge, this is the first report of empyema thoracis caused by <i>Clavispora lusitaniae</i> in a domestic cat. The described case emphasises the primary importance of timely identification of pathogenic agent(s) of feline pyothorax and appropriately prescribed treatment for the prevention of severe complications and fatal outcomes.