Bronchiectasis

BRONCHIECTASIS
BRONCHIECTASIS

Bronchiectasis

Overview

Bronchiectasis is an irreversible widening or dilation of portions of the airways or bronchi resulting from damage to the bronchial wall. In other words, it’s a term used to describe the abnormal dilatation of bronchi.

  • Bronchiectasis can result from several conditions that injure the bronchial wall directly or indirectly by interfering with its normal defenses against potentially harmful substances.
  • The most common cause is severe respiratory infections.
  • Immune deficiency disorders, hereditary disorders such as cystic fibrosis (a disorder in which abnormal mucus impairs the ability of cilia to clear the bronchi of the organisms that cause infections) and mechanical factors such as bronchial obstruction (caused by an inhaled object, a lung tumor or other disorders) may predispose a person to infections that lead to bronchiectasis.
  • A small number of cases probably result from inhaling toxic substances that injure the bronchi, such as noxious fumes, gases, smoke (including tobacco smoke) and injurious dust (silica and coal dust).
  • In bronchiectasis areas of the bronchial wall are destroyed and become chronically inflamed, ciliated cells are damaged or destroyed and secretions or mucus accumulate.
  • Also, the bronchial wall becomes less elastic. The affected airways become wider and flabby and may develop outpouchings or sacs that may resemble tiny balloons.
  • The increased mucus production promotes the growth of bacteria, often obstructs the bronchi, and leads to the pooling of infected secretions and further damage to the bronchial wall.
  • The inflammation and infection can extend to small air sacs of the lungs (alveoli) and produce pneumonia, scarring and a loss of functioning lung tissue.
  • In severe cases, scarring and a loss of blood vessels in the lungs can ultimately strain the right side of the heartas the heart rises to pump blood through the altered vessels.
  • Also, inflammation and an increased number of blood vessels in the bronchial wall (which are fragile) can result in a person coughing up blood.
  • Blockage of the damaged airways can lead to abnormally low levels of oxygen in the blood.
  • Bronchiectasis may affect many areas of the lung or it may appear in only one or two areas.
  • Typically, bronchiectasis causes the widening of medium-sized bronchi, but often smaller bronchi becomes scarred and destroyed.
  • Occasionally, a form of bronchiectasis affecting larger bronchi occurs in allergic bronchopulmonary aspergillosis, a condition caused by an allergic response to Aspergillus fungus.

Symptoms

  • Bronchiectasis can develop at any age of ten, the process begins in early childhood.
  • However, symptoms may not appear until much later.
  • In most people, symptoms begin gradually, usually after a respiratory infection and tend to worsen over the years.
  • Most people develop a chronic cough that produces sputum.
  • The amount and type of sputum depends on how extensive the disease is and whether there is complicating infection.
  • Often the person has coughing spells only early in the morning and late in the day.
  • Coughing up of blood is common and may be the first or only symptom.
  • Recurrent fever or chest pain, with or without frequent bouts of pneumonia, may also occur.
  • People with widespread bronchiectasis may develop wheezing or shortness of breath.
  • They may also have chronic bronchiectasis, which occur more commonly in underdeveloped countries and in people who have cystic fibrosis, may impair breathing and the lungs ability to oxygenate the blood and rid the body of carbon dioxide, a condition called respiratory failure.
  • Very severe bronchiectasis may also strain the right side of the heart and lead to cor pulmonale.

Selected Causes of Bronchiectasis

Respiratory infections

  • Bacterial infections such as a whooping cough or infections caused by Klebsiella, Staphylococcus, or Pseudomonas.
  • Fungal infection such as Aspergillosis.
  • Mycobacterial infection such as tuberculosis.
  • Viral infection such as influenza, adenoviral infection, respiratory syncytial virus infection or measles.
  • Mycoplasma infection.

Bronchial obstruction

  • Inhaled object.
  • Enlarged lymph glands.
  • Lung tumor.
  • Mucus plug.

Inhalation injuries

  • Injury from noxious fumes, gases or particles.
  • Inhalation of stomach acid and food particles.

Hereditary conditions

  • Cystic fibrosis
  • Primary ciliary dyskinesia, including Kartagener’s syndrome
  • Marfan syndrome

Immunologic abnormalities

  • Immunoglobulin deficiency syndromes.
  • White blood cell dysfunction.
  • Complement deficiencies
  • Certain autoimmune or hyper-immune disorders such as rheumatoid arthritis and ulcerative colitis.

Other conditions

  • Drug abuse such as Heroin abuse.
  • HIV infection
  • Young’s syndrome (obstructive azoospermia)
  • Yellow nail syndrome (with lymphedema)

Congenital causes

  • Ciliary dysfunction syndromes
    • Primary ciliary dyskinesia
    • Kartagener’s syndrome
  • Cystic fibrosis
  • Primary hypogammaglobulinemia

Acquired causes in adults

  • Pulmonary TB
  • Supportive pneumonia
  • Bronchial tumors
  • Allergic bronchopulmonary aspergillosis complicating asthma

Acquired causes in children

  • Primary TB
  • Inhaled foreign object
  • Pneumonia

Diagnosis

  • Doctors may suspect bronchiectasis because of a person’s symptoms or the presence of a condition thought to cause bronchiectasis.
  • Tests are performed to confirm the diagnosis and assess the extent and location of the disease.
  • Chest X-rays can often detect the lung changes caused by bronchiectasis, however , occasionally results are normal.
  • Computed tomography is usually the most sensitive test to identify and confirm the diagnosis and to determine the extent and severity of the disease; these are important factors when surgical treatment is being considered.
  • After bronchiectasis is diagnosed, tests are often performed to check for diseases that may be causing or contributing to it if they were not previously identified.
  • Such tests may include measuring the immunoglobulin levels in blood, testing for HIV infection and other immune system disorders, measuring the salt levels in sweat (which are abnormal in people with cystic fibrosis) and examining nasal, bronchial or sperm specimens with a special microscope and other tests to determine if the cilia are structurally or functionally defective.
  • When bronchiectasis is limited to one area: for example, a lung lobe or segment – doctors may perform bronchoscopy to determine an inhaled foreign objector lung tumor is the cause.
  • Other tests may be performed to identify underlying diseases such as allergic bronchopulmonary aspergillosis or tuberculosis.
  • Genetic testing for cystic fibrosis may be needed when there is a family history, repeated respiratory infections, or other suspicious findings in a child or young adult, even when other features of typical cystic fibrosis are absent.

Prevention

  • Early identification and treatment of conditions that tend to cause bronchiectasis may prevent the development of bronchiectasis or reduce its severity.
  • More than half the cases of bronchiectasis in children can be accurately diagnosed and promptly treated.
  • Childhood immunization against measles and whooping cough, appropriate use of antibiotics and improved living conditions and nutrition have significantly reduced the number of people who develop bronchiectasis.
  • Annual influenza vaccines, use of pneumococcal vaccines and use of appropriate drugs early in the course of infections (such as pneumonia and tuberculosis) helps to prevent bronchiectasis or reduce its severity.
  • Receiving immunoglobulin for an immunoglobulin deficiency syndrome may prevent recurring infections.
  • In people who have allergic bronchopulmonary aspergillosis, the appropriate use of corticosteroids and perhaps the antifungal drug itraconazole may reduce the bronchial damage that results in bronchiectasis.
  • Avoiding toxic fumes, gases, smoke and injurious dusts also helps prevent bronchiectasis or reduce its severity.
  • Inhalation of foreign objects into the airways by children may be prevented by carefully watching what they put in their mouth.
  • Additionally, avoiding oversedation from drugs or alcohol and seeking medical care for neurologic symptoms (such as impaired consciousness) or gastrointestinal symptoms (such as difficulty in swallowing and regurgitation or coughing after eating) may help to prevent aspiration.
  • Also, drops of mineral oil or other oils should never be placed in the mouth or nose because they can be inhaled into the lungs.

Treatment and Prognosis

  • Treatment of bronchiectasis is directed against eradicating infections, decreasing the buildup of mucus and inflammation, relieving airway obstruction and reducing complications such as coughing up of blood, low oxygen levels in the blood, respiratory failure and cor pulmonale.
  • Drugs that suppress coughing may worsen the condition and should not be used.
  • Infections are treated with antibiotics, bronchodilators and physical therapy to promote drainage of secretions.
  • Sometimes antibiotics are prescribed for a long period to prevent recurring infections, especially in people who have cystic fibrosis.
  • For inflammation and buildup of mucus, anti-inflammatory drugs such as inhaled corticosteroids and drugs that thin this pus and mucus may also be given, although the effectiveness of mucolytics is uncertain.
  • To help drain the mucus, postural drainage and chest percussion are used.
  • To detect and treat bronchial obstruction, bronchoscopy can be used before severe damage occurs.
  • Rarely, a part of a lung needs to be surgically removed.
  • Such surgery usually is an option only if the disease is confined to one lung, or preferably to one lung lobe or segment.
  • Surgery may be considered for people who have recurrent infections despite treatment or who cough up large amounts of blood.
  • Alternatively, a doctor may deliberately block a bleeding bronchial vessel by using a procedure called bronchial arterial embolization.
  • If the person’s blood oxygen level is low, oxygen therapy may help prevent complications such as cor pulmonale.
  • If the person has wheezing or shortness of breath, corticosteroids taken with or without bronchodilators often help.
  • Respiratory failure if present, should be treated.
  • Lung transplantation can be performed in certain people who have advanced bronchiectasis, mostly those who also have advanced cystic fibrosis.
  • Five years survival rates as high as 65 to 75% have been reported when a heart-lung or a double lung transplantation is used.
  • Pulmonary function as measured by the amount of air in the lungs and the rate and amount of air moving in and out of the lungs with each breath, usually improves within 6 months and the improvement may be sustained for at least 5 years.
  • The overall prognosis for people with bronchiectasis depends on how well infection and other complications are prevented or controlled.
  • Because other conditions diminish the effectiveness of prevention and treatment, people with these conditions tend to have a worse prognosis.

Bronchiectasis life expectancy

  • In mild bronchiectasis there is no shortage of life expectancy.
  • In very severe bronchiectasis, however, some patients die at a younger age because of their lung disease.

Additional information for professionals

Pathology

  • Granulation tissue, Squamous epithelium, and normal ciliated epithelium are the areas where bronchiectatic cavities are lined up.
  • Inflammatory changes may be present in the deeper layers of the bronchial wall.
  • Hypertrophy of the bronchial arteries may also be present.
  • Fibrotic changes and chronic inflammatory changes can be present in the surrounding lung tissue.

Clinical Features

  • The symptoms of bronchiectasis are mentioned above as well as on the next tab.
  • Physical signs in the chest may be unilateral or bilateral.
  • If secretions are absent in the bronchiectatic airways and if the associated lobar collapse is also absent, there are no abnormal physical signs.
  • Coarse crackles can be heard over the affected areas if there is a large amount of sputum in the bronchiectatic spaces.
  • If lobar collapse is present, physical signs and symptoms depend on whether the proximal bronchus supplying the collapsed lung is blocked or not. If that bronchus is blocked, breathing sounds are diminished.

Symptoms

Symptoms which occurs due to the accumulation of pus in the dilated bronchi

  • Chronic productive cough
    • This is worse in the mornings.
    • Also occurs with a sudden change in posture.
    • Sputum is abundant in quantity and is continuously discharging pus in the advanced stage of the disease.
    • Bad breath (halitosis) is a common accompanying symptom.

Symptoms which occurs due to inflammatory changes in lung and pleura surrounding the dilated bronchi

  • Following symptoms can be observed when pneumonia occurs due to spread of infection
    • Fever
    • Malaise
    • Increased cough
    • Increased sputum volume
  • This pneumonia may be associated with pleurisy.
  • Recurrent pleurisy often occurs in the same site in bronchiectasis.

Haemoptysis

  • In bronchiectasis, hemoptysis is often recurrent in nature.
  • This could be mild to severe.
  • This is usually associated with sputum containing pus.
  • An increase in the discharge of pus in the sputum can also be observed.
  • In the case of dry bronchiectasis, hemoptysis may be the only symptom.

Symptoms related to general health

  • In the advanced stage of the disease, sputum continuously discharges pus.
  • Other symptoms include:
    • Weight loss
    • Anorexia
    • Lack of energy
    • Low – grade fever
    • Digital clubbing

Investigations

Bacteriological and mycological examination of sputum

  • A sputum culture may reveal Pseudomonas aeruginosa, fungi like Aspergillus and other Mycobacteria in addition to common respiratory pathogens.
  • Resistant strains should be identified by repeating sputum culture at regular intervals and appropriate treatment should be advised or prescribed to the patient.

Radiological examination

  • Bronchiectasis is not evident (usually) on a chest X-ray.
  • Thickened airway walls, cystic bronchiectatic spaces and associated areas of pneumonic consolidation or collapse may be visible in the advanced stages of the disease.
  • Computed Tomography (CT) scan being more sensitive than the X-ray, shows thickened dilated airways.

Assessment of ciliary function

  • This can be done by placing a small pellet of saccharin in the anterior portion of the nose.
  • The patient can taste this saccharin pellet when it reaches the pharynx.
  • Time taken for Saccharin pellet to travel from the anterior portion of the nose to pharynx is measured.
  • This time should not exceed 20 minutes.
  • In patients suffering from ciliary dysfunction syndrome, this time is greatly prolonged.
  • Biopsy of the nose should be performed to assess ciliary beat frequency.
  • Electron microscopy should be utilized to detect the structural abnormalities of the cilia.