Bronchiectasis

Picture of the lungs

• Bronchiectasis describes damage to the walls of the bronchial tubes with loss of the smooth muscle and loss of elasticity of segments of the bronchi. The resultant airway distortion prevents secretions from being adequately cleared from the lung.
• Bronchiectasis may be congenital or acquired. Cystic fibrosis is the most common cause of congenital bronchiectasis.
• Symptoms of bronchiectasis include
  • increased sputum production,
  • bloody sputum,
  • shortness of breath,
  • weakness, and
  • fatigue.
• Diagnosis is often made by history and confirmed by CT scan of the chest. Efforts may be made to find the underlying cause of bronchiectasis.
• Complications include recurrent pneumonia, respiratory failure, and heart failure.
• Bronchiectasis is not curable. The goal for treatment is to control secretions and minimize the risk of infections.

Bronchiectasis is a term that describes damage to the walls of the bronchial tubes, of the lung. Inflammation due to infection or other causes destroys the smooth muscles that allow the bronchial tubes to be elastic and prevents secretions that are normally made by lung tissue to be cleared.

Normal branching of the airways of the lung demonstrates a gentle taper that occurs at each branch point, like the branches of a tree. This tapering results in decreased resistance in the larger branches, enabling mucus or other objects to be funneled to the larger airways and eventually, with a cough, ejected out through the mouth. Loss of this normal anatomic tapering of the airways by damage due to inflammation causes the walls of the airways to be irregularly shaped. Secretions tend to pool in the distorted airways rather than be expelled, and these stagnant secretions are a breeding ground for bacterial growth. These bacteria, in turn, cause further irritation and inflammation, airway damage, and hence more secretions, initiating a "vicious cycle" of damage. This increases the risk of infections to spread directly into the airspaces of the lungs resulting in pneumonia.

Bronchiectasis is a form of chronic obstructive pulmonary disease (COPD), which also includes emphysema and chronic bronchitis. A person may have bronchiectasis with no other associated diseases or conditions; however, it usually is associated with other conditions (like COPD, emphysema, and chronic bronchitis).

Congenital bronchiectasis may occur due to a genetic defect such as occurs in cystic fibrosis. Usually, the disease Alpha-1 antiprotease (alpha 1- antitrypsin) deficiency results in emphysema, but bronchiectasis can occur as well in this condition. An embryologic defect in the airway cilia, so-called immotile cilia syndrome, is another cause of bronchiectasis and is often associated with situs inversus, in which the major organs are in a reversed position (for example, the heart is on the right).

Lung infections in children, especially pertussis, may ultimately lead to lung destruction and bronchiectasis later in life. Therefore, prevention is an important part of treatment, which includes adequate immunizations and avoiding secondhand smoke and other toxic fumes.

Bronchiectasis is characterized by an increased amount of sputum production (mucus produced and coughed up from the lung), recurrent infections, and gradual loss of lung function leading to shortness of breath.

Bronchiectasis develops over a prolonged period of time.

Common symptoms include recurrent cough and sputum production. Usually the mucus is clear, but it may be bloody due to bronchial wall injury or green or yellow if infection is present. Shortness of breath and fatigue develop as lung function decreases. The person may experience wheezing.

If the disease progresses or if it is poorly controlled, the amount of work required to breathe increases and weight loss and diminished quality of life may occur.

Bronchiectasis may occur due to another underlying disease. Symptoms of that primary disease may also be present. For example, a patient with tuberculosis may have bloody sputum, fever, chills, and night sweats. A person with Crohn's disease may have abdominal pain and diarrhea.

Congenital bronchiectasis often becomes apparent because of recurrent pneumonia.

Bronchiectasis is caused by damage to the larger airway walls destroying the muscles and elastic tissue layers that allow normal bronchial tubes to contract. This damage decreases the ability of the lung to move and clear secretions that are normally produced in the lung. These pooled secretions cause increased potential for infection like pneumonia and bronchitis, which causes further damage to the bronchial walls. As mentioned above, this results in a vicious cycle in which increased damage leads to increased infection, leading to further damage.

There are three primary types of bronchiectasis. These types are described by their anatomical appearance.

1. Cylindrical bronchiectasis is the mildest form and reflects the loss of the normal tapering of the airways. The symptoms may be quite mild, like a chronic cough, and usually are discovered on CT scans of the chest.
2. Saccular bronchiectasis is more severe, with further distortion of the airway wall and symptomatically, affected persons produce more sputum.
3. Cystic bronchiectasis is the most severe form of bronchiectasis, and fortunately it is the least common form. This often occurred in the pre-antibiotic era when an infection would run its course and the patient would survive with residual lung damage. These patients often would have a chronic productive cough, bringing up a cup or more of discolored mucus each day.

Bronchiectasis also may be congenital or acquired.

Congenital causes of bronchiectasis

• Cystic fibrosis
• Kartagener syndrome
• Young's syndrome
• Alpha-1-antitrypsin deficiency

Acquired causes of bronchiectasis

• Recurrent infection
• Aspiration of foreign bodies or other materials
• Inhaling toxic gases like ammonia
• Alcohol and drug abuse
• Tuberculosis
• Inflammatory bowel disease (ulcerative colitis, Crohn's disease)

Any person with unexplained shortness of breath or chronic cough should seek medical care.

Usually, people who develop bronchiectasis do so over a prolonged period of time. They seek medical care because of chronic cough, a progressive increase in sputum production, and/or, shortness of breath at rest or exercise. Recurrent pneumonia is also a reason that people may seek care. The symptoms of pneumonia include fever, cough, and shortness of breath.

Bronchiectasis may cause hemoptysis (coughing up blood). This is never normal, and medical attention is needed if hemoptysis occurs. Other reasons for coughing up blood include bronchitis, pneumonia, congestive heart failure, tuberculosis, pulmonary emboli (blood clots in the vessels of the lung), and lung tumors.

Diagnosis of bronchiectasis begins with history and physical examination.

The patient will complain of daily cough and sputum production that may or may not be bloody due to damage to the bronchial tubes or from infection. Shortness of breath with activity or at rest, wheezing, fatigue, and chest pain are all common complaints.

Physical examination may be relatively normal, or lung examination may reveal wheezing and crackles. Depending up on the severity of disease and how long it has been present, other findings may include weight loss, cyanosis (a bluish color of the skin and the mucous membranes due to an insufficient level of oxygen), and right heart failure (manifested by shortness of breath, leg swelling, and liver enlargement).

The history and physical exam may lead to the suspicion of the diagnosis and the health care practitioner may order a high resolution chest CT scan, which will confirm the diagnosis. The CT may also help in finding the underlying reason why bronchiectasis developed.

Plain chest X-rays may be used in helping make the diagnosis and help track the progression of the disease, but these findings are often much more subtle than those seen by CT scans.

Once the diagnosis of bronchiectasis is made, the underlying cause needs to be found. Blood tests and sputum tests may be indicated depending upon the clinical situation. Often a lung specialist (pulmonologist) will be consulted to help direct the investigation and testing.

Pulmonary function studies or pulmonary function tests (PFTs) may be helpful in assessing what kind and how much lung damage has occurred. Bronchiectasis is a form of chronic obstructive pulmonary disease (COPD), and this testing can help confirm this. These tests can help determine whether the lung tissue will respond to the use of bronchodilator treatment with inhaler medications (please see treatment section). Repeated over time, pulmonary function studies can help document the benefits of treatment or progression of the disease.

Less commonly, bronchoscopy is used to look inside the airways with a fiberoptic camera. This is sometimes done to look for tumors or foreign bodies that may have been seen on CT. In some cases, bronchoscopy can be used therapeutically to remove excessive retained secretions.

Screening for cystic fibrosis occurs for all newborns.

Bronchiectasis is not a curable disease. Instead, the goal of treatment is control of secretions and preventing infections. In some situations, where the disease is limited to one area of the lung, surgery may be a possibility to remove the area affected by the disease.

Basic lung hygiene is required for all patients with bronchiectasis:

• Keep immunizations up to date to prevent infections.
• Drink plenty of fluids to make mucous secretions less sticky.
• Quit smoking and avoid secondhand smoke.
• Get adequate nutrition by consuming necessary calories. For some people, breathing requires increased effort and thus and requires increased nutrition.

Chest physical therapy

The basis for bronchiectasis treatment is chest physical therapy to assist in coughing up secretions, and antibiotics to prevent infection.

Since the smooth muscles that surround the bronchial tubes are damaged, mechanical ways to clear secretions are used to increase air flow and decrease the risk of infection. Chest physical therapy uses percussion or clapping on the back to help loosen secretions and then changing positions of the body to allow gravity to help those secretions to be coughed up. Chest clapping may be done by a physical therapist, but family members can be taught to do this routinely at home. Mechanical devices such as chest clappers or vests also may be considered.

Antibiotics may be prescribed to treat an infection that occurs or they may be used as prophylaxis to prevent infection. The choice of antibiotics depends upon the clinical situation and may be guided by blood or sputum cultures that will try to identify the bacteria causing the infection, and the type of antibiotic that will effectively treat the infection. Many patients may be kept on a revolving course of different antibiotics over their lifetime. Inhaled antibiotics have been used in addition to medications taken by mouth. In patients with more severe lung infections, intravenous antibiotics may be required.

Medications may also be used to loosen secretions, dilate bronchial tubes and decrease inflammation, hopefully decreasing the risk of infection.

Routine used of inhaled steroids (for example, fluticasone propionate oral inhaler [Flovent]) using a hand held puffer may decrease production of secretions, allow dilation of bronchial tubes, and prevent progression of bronchiectasis. Inhaled steroids may not have enough anti-inflammatory activity, and in unusual cases, steroids taken by mouth (prednisone) may also be required.

Bronchodilator (for example, albuterol, ProAir, Ventolin HFA, Proventil HFA) and anticholinergic (for example, ipratropium bromide inhaler [Atrovent], tiotropium bromide inhalation powder [Spiriva]) inhaled medications dilate bronchial tubes and increase air flow into the lungs, making it easier for secretions to be cleared. The medication can be inhaled using a hand held puffer or with a nebulizer machine. Often, combination therapy with both a bronchodilator and inhaled corticosteroid (fluticasone and salmeterol oral inhaler [Advair], budesonide and formoterol fumarate dihydrate [Symbicort]) are prescribed.

Home oxygen supplementation may be needed if lung function decreases to the point atmospheric air does not supply enough oxygen to the body.

Some patients have only a small area of bronchiectasis, and surgery may be an option to remove the small segment of affected lung in these individuals. Surgery may be considered in other situations to remove part of a lung where infection cannot be controlled or where excessive bleeding cannot be managed.

Bronchiectasis decreases the ability of the lung to mobilize secretions, leading to recurrent infection, increased sputum production, and difficulty breathing.

Decreased air entry into the lung through the bronchial tubes decreases oxygen availability in the bloodstream, causing shortness of breath with activity and ultimately at rest. This decreased oxygen level over time causes constriction of the pulmonary arteries, resulting in increased pressure in these arteries, referred to as pulmonary hypertension. Overcoming these pressures forces the heart to work harder causing the right ventricle to thicken, a condition called cor pulmonale. Eventually, the right side of the heart (which pumps blood to the vessels of the lung) may fail, resulting in increased fluid accumulation in the legs or abdominal cavity.

Bronchiectasis may result in coughing up blood (hemoptysis).

Hospitalization may be required for pneumonia, massive hemoptysis, respiratory failure (when not enough oxygen is present in the bloodstream), and heart failure. Heart failure and respiratory failure are the common causes of death in patients with bronchiectasis. In some cases, due to prolonged use of antibiotics, infections with antibiotic-resistant bacteria may develop that require special antibiotics that are usually given in the hospital through an intravenous (IV) line.

Early recognition and adequate treatment can help control bronchiectasis and decrease symptoms. Life- long awareness of the need for treatment may allow people with bronchiectasis to minimize complications and maximize life expectancy.

The outlook depends upon the underlying reason for developing bronchiectasis. Congenital causes of bronchiectasis, like cystic fibrosis, may have a worse prognosis than acquired diseases.