Bronchiectasis (brong-ke-EK-ta-sis) is a condition in which damage to the airways causes them to widen and become flabby and scarred. The airways are tubes that carry air in and out of your lungs.
Bronchiectasis usually is the result of an infection or other condition that injures the walls of your airways or prevents the airways from clearing mucus. Mucus is a slimy substance that the airways produce to help remove inhaled dust, bacteria, and other small particles.
In bronchiectasis, your airways slowly lose their ability to clear out mucus. When mucus can’t be cleared, it builds up and creates an environment in which bacteria can grow. This leads to repeated, serious lung infections.
Each infection causes more damage to your airways. Over time, the airways lose their ability to move air in and out. This can prevent enough oxygen from reaching your vital organs.
Bronchiectasis can lead to serious health problems, such as respiratory failure, atelectasis (at-eh-LEK-tah-sis), and heart failure.
Prior to the introduction of widespread immunisations programs, bronchiectasis often occurred as the result of infection with measles or whooping cough.
Currently bronchiectasis usually occurs as the result of an illness such as pneumonia (approximately 25% of all cases). Other causes include:
- Cystic fibrosis
- Immune deficiency
- Recurrent aspiration of fluid into the lungs (as occurs with gastroesophageal reflux)
- Inhalation of a foreign object into the lungs (if left untreated)
- Inhalation of harmful chemicals eg: ammonia
- In rare cases it may be congenital (present at birth).
- In many cases the underlying cause of the condition is unable to be identified.
Bronchiectasis is an abnormal dilation of the proximal and medium-sized bronchi (>2 mm in diameter) caused by weakening or destruction of the muscular and elastic components of the bronchial walls. Affected areas may show a variety of changes, including transmural inflammation, edema, scarring, and ulceration, among other findings. Distal lung parenchyma may also be damaged secondary to persistent microbial infection and frequent postobstructive pneumonia. Bronchiectasis can be congenital but is most often acquired.
Congenital bronchiectasis usually affects infants and children. These cases result from developmental arrest of the bronchial tree.
Acquired forms occur in adults and older children and require an infectious insult, impairment of drainage, airway obstruction, and/or a defect in host defense. The tissue is also damaged in part by the host response of neutrophilic proteases, inflammatory cytokines, nitric oxide, and oxygen radicals. This results in damage to the muscular and elastic components of the bronchial wall. Additionally, peribronchial alveolar tissue may be damaged, resulting in diffuse peribronchial fibrosis.
The result is abnormal bronchial dilatation with bronchial wall destruction and transmural inflammation. The most important functional finding of altered airway anatomy is severely impaired clearance of secretions from the bronchial tree.
Impaired clearance of secretions causes colonization and infection with pathogenic organisms, contributing to the purulent expectoration commonly observed in patients with bronchiectasis. The result is further bronchial damage and a vicious cycle of bronchial damage, bronchial dilation, impaired clearance of secretions, recurrent infection, and more bronchial damage.
In 1950, Reid characterized bronchiectasis as cylindrical, cystic, or varicose in nature. Cylindrical bronchiectasis involves diffuse mucosal edema, with resultant bronchi that are dilated but have straight, regular outlines that end squarely and abruptly.
The main symptom of bronchiectasis is a mucus-producing cough. The cough is usually worse in the mornings and is often brought on by changes in posture. The mucus may be yellow-green in colour and foul smelling, indicating the presence of infection.
Other symptoms may include:
- Coughing up blood (more common in adults)
- Bad breath
- Wheezing chest – a characteristic crackling sound may be heard when listening with a stethoscope.
- Recurring lung infections
- A decline in general health
- In advanced bronchiectasis, breathlessness can occur.
The onset of symptoms often occurs slowly. As the disease progresses, coughing worsens and increasing amounts of mucus are produced.
Your doctor may suspect bronchiectasis if you have a daily cough that produces large amounts of sputum (spit).
To find out whether you have bronchiectasis, your doctor may recommend tests to:
- Identify any underlying causes that require treatment
- Rule out other causes of your symptoms
- Find out how much your airways are damaged
- Diagnostic Tests and Procedures
CHEST CT SCAN
A chest computed tomography (to-MOG-ra-fee) scan, or chest CT scan, is the most common test for diagnosing bronchiectasis.
This painless test creates precise pictures of your airways and other structures in your chest. A chest CT scan can show the extent and location of lung damage. This test gives more detailed pictures than a standard chest x ray.
CHEST X RAY
This painless test creates pictures of the structures in your chest, such as your heart and lungs. A chest x ray can show areas of abnormal lung and thickened, irregular airway walls.
Your doctor may recommend other tests, such as:
- Blood tests. These tests can show whether you have an underlying condition that can lead to bronchiectasis. Blood tests also can show whether you have an infection or low levels of certain infection-fighting blood cells.
- A sputum culture. Lab tests can show whether a sample of your sputum contains bacteria (such as the bacteria that cause tuberculosis) or fungi.
- Lung function tests. These tests measure how much air you can breathe in and out, how fast you can breathe air out, and how well your lungs deliver oxygen to your blood. Lung function tests help show how much lung damage you have.
- A sweat test or other tests for cystic fibrosis.
If your bronchiectasis doesn’t respond to treatment, your doctor may recommend bronchoscopy (bron-KOS-ko-pee). Doctors use this procedure to look inside the airways.
During bronchoscopy, a flexible tube with a light on the end is inserted through your nose or mouth into your airways. The tube is called a bronchoscope. It provides a video image of your airways. You’ll be given medicine to numb your upper airway and help you relax during the procedure.
Bronchoscopy can show whether you have a blockage in your airways. The procedure also can show the source of any bleeding in your airways.
Bronchiectasis is a chronic (long-term) condition that requires lifelong maintenance. Good management of the condition is vital to prevent ongoing damage to the lungs and worsening of the condition.
The ultimate goal of treatment is to clear mucus from the chest and prevent further damage to the lungs. The two main types of treatments used are:
Some or all of the following groups of medications may be used:
- Antibiotics are used to treat acute lung infections. Where the infection is severe, hospitalisation and treatment with intravenous antibiotics may be required.
- Bronchodilators (as used in people with asthma) to improve the flow of air to the lungs.
- Corticosteroids to reduce inflammation in the lungs.
- Occasionally, medications to thin the mucus may be used.
- Vaccination against flu and pneumococcous.
PHYSIOTHERAPY AND EXERCISE
Chest physiotherapy and postural drainage are used to remove secretions from the lungs. An individual program is usually developed where exercise and breathing techniques to clear the lungs of mucus are taught.
Other factors important in managing the condition include avoiding dust, smoke and other respiratory irritants, and maintaining a balanced nutritious diet.
It is also important to identify and treat any underlying conditions that lead to the development of bronchiectasis.
In some cases of severe bronchiectasis, surgery may be suggested to remove the affected portion of the lung. However this is only an option if the disease is localised in one or two small areas of the lungs.