Bronchiectasis in Cats
A cat's trachea, or wind pipe, is divided into two main bronchi, or tubes, which feed air into the lungs. The two tubes that begin the bronchial tree further divide into smaller branches, which further divide several more times to form bronchial tree.
In bronchiectasis, the bronchi are irreversibly dilated due to a destruction of the elastic and muscular components in the airway walls. This may occur with or without accompanying accumulation of lung secretions. Dilatation may be associated with infections of the bronchi, pneumonia, lung damage, chronic bronchitis (inflammation), decreased functional capacity of lungs, or abnormal cell growth (neoplasia).
This condition is rarely seen in the cat population, but when it does occur, it tends to affect older male cats.
Symptoms and Types
- Chronic cough (moist and productive)
- Hemoptysis (coughing up blood) in some cats
- Intermittent fever
- Exercise intolerance
- Rapid breathing
- Difficulty in breathing normally, especially after exercise
- Chronic nasal discharge
- Primary ciliary dyskinesia (malfunction of the mucous clearing cilia in the lungs)
- Long-standing infections
- Inadequately treated infections or inflammations in the lungs
- Smoke or chemical inhalation
- Aspiration pneumonia (pneumonia caused by food, vomit, or other content being breathed into lungs)
- Radiation exposure
- Inhalation of environmental toxins followed by infections
- Obstruction of bronchi due to a foreign body
- Neoplasia of the lungs
There are variable causes which may lead to bronchial inflammation in your cat. Therefore, a detailed history and a complete physical examination are essential for diagnosis. You will need to give your veterinarian a thorough history of your cat's health, the onset of symptoms, and possible incidents that might have led to this condition. Standard laboratory testing will include complete blood count (CBC), biochemistry profiling, and urinalysis. Blood gas analysis will indicate the functional capability of the lungs.
These tests will be helpful in looking for infections or other changes related to the underlying disease. Your veterinarian will also take x-ray images of the chest, respiratory tract, and bronchial tubes, which may or may not show abnormalities in the architecture of the lungs, including dilatation of the bronchi.
It is hoped that x-rays will reveal characteristic abnormalities in the bronchi that are related to this disease, but that is not always the case. Other changes in the lungs pertaining to chronic infections typically can be visualized using x-rays. Long term inflammation will leave evidence that can be visually examined. More sensitive testing, like computed tomography (CT) scanning, can be used for some patients, and this test may reveal more detailed information about structural changes within lungs. Your veterinarian will also take samples of tissue and fluid from the bronchi for laboratory evaluation.