Case History: 4-years old normal short haired European type of female cat was presented to the clinic with sever dyspnoea and cyanotic mucous membranes. At the time the cat hospitalized she showed a severely disturbed general state. The cat was so apathetic and during percussion horizontal dullness was detected. Other organs out of thorax didn't show abnormalities. An intravenous catheter was installed for medication and blood sample were taken for hematology examination. Additional clinical examination like Thoracic radiography revealed lift-sided blurring of the thorax indicative for pleural effusion. By thoracocentesis purulent greenish fluid was obtained. The result of the cytological examination was septic exudates in pleural cavity.

Diagnosis: Septic pleuritis (pyothorax) which is characterized by the presence of septic exudates and consequently bacterial contamination of the pleural cavity.

Treatment: Involves antibiotics, drainage of the pleural cavity and supportive care. e.g., intravenous fluid therapy. The stabilization of the patient was achieved through intravenous fluid administration, bronchodilatators, (Aminophyllin) and vitamins. As an antibiotic treatment Cobactan (cephalosporin) was employed.