Narrowed Bronchi in Cats

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
• Lethargy
• Exercise intolerance
• Rapid breathing
• Difficulty in breathing normally, especially after exercise
• Chronic nasal discharge

Causes

• 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

Diagnosis

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.

Treatment

In case of severe disease, your cat may need to be hospitalized for a few days. Emergency treatment will be given to overcome the crisis. Fluid therapy, oxygen therapy, and removal of viscid fluid from lungs will be conducted. Antibiotics are often used to eradicate the infectious organism, and physiotherapy can be used to enhance the clearance of secretions from lungs. Your veterinarian will recommend minimizing any exposure to irritants such as dust, smoke, aerosol compounds, and air fresheners, which can further complicate the disease. Anti-inflammatory medications may help to reduce your cat's symptoms, making breathing easier. In severe cases, surgical removal of the affected lung lobe may be required.

Living and Management

If disease is affecting a small area of the lungs, the affected lung lobe will be removed in order to effectively resolve the underlying disease. Prognosis is excellent for animals that are treated early, before significant inflammation or permanent scarring has taken place.

Even in patients with resolution of the underlying disease or removal of the affected lobe, secondary infections are common. This is due to the diffuse nature of this disease, which often leads to complications. Or, some patients may take longer to completely recover due to the chronic nature of problem, the age or previous health condition of the cat, or because another underlying disease was not cured.

You will need to visit your veterinarian at regular intervals so that your cat's progress can be followed, and so therapy and medication changes can be made appropriately, depending on your cat's status. Follow-up care is of paramount importance in improving the prognosis for your cat.

You may need to devote extra care and affection to your cat during the recovery period, also paying strict attention to the medication guidelines and scheduling in order to prevent further complications. Extra patience will be required, as you assist your cat in its daily needs, and keep it protected from undue stress. A calm and quite space, away from active children and pets, will help your cat to rest and heal.

Do not use anything in the home that will place unneeded stress on your cat's bronchial airways. Fireplaces, air fresheners, cleaning products and chemicals are just some of the things that can irritate your cat's respiratory tract. A place set aside where your cat can be taken when you are using any of these products is the best measure for protecting your cat from an attack on its bronchial tubes.

If you see a return of any of the symptoms described above, immediately call your veterinarian or take your cat to a veterinary hospital. It is not uncommon for a recurrence of emergency crisis to occur in these cases.

The prognosis is highly variable depending on the nature of the disease, the areas of the lungs being affected, the diffuse or focal nature of the disease, and the presence or absence of concurrent infections in the body. If treated properly, these patients can live well for number of years.