What is pyothorax?
Pyothorax refers to the presence of infected fluid and bacteria (pus) within the chest cavity.
What causes pyothorax?
Pyothorax is usually caused by a bacterial infection in the chest cavity. Usually, pus is present in both sides of the chest although occasionally only one side will be affected.
The source of the infection is rarely found although possible causes include:-
1. Penetrating wounds to the chest wall.
2. Wounds to internal structures such as the oesophagus (food pipe), trachea (wind pipe) for example following ingestion or inhalation of a foreign body.
3. Migrating foreign body such as a grass seed which entered the body elsewhere.
4. Extension of infection from a lung infection (pneumonia) - this is the most likely cause in the majority of cases.
What are the clinical signs seen with pyothorax?
Rapid shallow breathing which may be painful, depression, lethargy and other signs of ill health such as a reluctance to eat are seen in most cats with pyothorax. The severity of these signs is extremely variable and rarely cats may suddenly die without having had any previous signs of illness.
Cats with pyothorax usually have a high temperature which contributes to some of the clinical signs seen. The breathlessness is caused by the presence of fluid in the chest which prevents the normal expansion of the lungs.