Bronchiectasis is a disease that causes localized, irreversible dilatation of part of the bronchial tree. Involved bronchi are dilated, inflamed, and easily collapsible, resulting in airflow obstruction and impaired clearance of secretions. Bronchiectasis is associated with a wide range of disorders, but it usually results from necrotizing bacterial infections, such as infections caused by the Staphylococcus or Klebsiella species or Bordetella pertussis.
Rene Theophile Hyacinthe Laënnec, the man who invented the stethoscope, used his creation to first discover bronchiectasis in 1819. The disease was researched in greater detail by Sir William Osler in the late 1800s; in fact, it is suspected that Osler actually died of complications from undiagnosed bronchiectasis.
Causes:
There are both congenital and acquired causes of bronchiectasis. Kartagener syndrome, which affects the mobility of cilia in the lungs, aids in the development of the disease. Another common genetic cause is cystic fibrosis, in which a small number of patients develop severe localized bronchiectasis. Young's syndrome, which is clinically similar to cystic fibrosis, is thought to significantly contribute to the development of bronchiectasis. This is due to the occurrence of chronic, sinopulmonary infections. Patients with alpha 1-antitrypsin deficiency have been found to be particularly susceptible to bronchiectasis, for unknown reasons. Other less-common congenital causes include primary immunodeficiencies, due to the weakened or nonexistent immune system response to severe, recurrent infections that commonly affect the lung.
Acquired bronchiectasis occurs more frequently, with one of the biggest causes being tuberculosis. Endobronchial tuberculosis commonly leads to bronchiectasis, either from bronchial stenosis or secondary traction from fibrosis. A especially common cause of the disease in children is Acquired Immune Deficiency Syndrome (AIDS), stemming from the human immunodeficiency virus. This disease predisposes patients to a variety of pulmonary ailments, such as pneumonia and other opportunistic infection. Bronchiectasis can sometimes be an unusual complication of inflammatory bowel disease, especially ulcerative colitis. It can occur in Crohn's disease as well, but does so less frequently. Bronchiectasis in this situation usually stems from various allergic responses to inhaled fungus spores. Recent evidence has shown an increased risk of bronchiectasis in patients with rheumatoid arthritis who smoke. One study stated a tenfold increased prevalence of the disease in this cohort. Still, it is unclear as to whether or not cigarette smoke is a specific primary cause of bronchiectasis.
Other acquired causes of bronchiectasis involving environmental exposures include respiratory infections, obstructions, inhalation and aspiration of ammonia and other toxic gases, pulmonary aspiration, alcoholism, heroin (drug use), and various allergies.
Diagnosis:
The diagnosis of bronchiectasis is based on the review of clinical history and characteristic patterns in high-resolution CT scan findings. Such patterns include "tree-in-bud" abnormalities and cysts with definable borders. In one small study, CT findings of bronchiectasis and multiple small nodules were reported to have a sensitivity of 80%, specificity of 87%, and accuracy of 80% for the detection of bronchiectasis. Bronchiectasis may also be diagnosed without CT scan confirmation if clinical history clearly demonstrates frequent, respiratory infections, as well confirmation of an underlying problem via blood work and sputum culture samples.
Treatment:
Treatment of bronchiectasis is aimed at controlling infections and bronchial secretions, relieving airway obstruction, and preventing complications. This includes the prolonged usage of antibiotics to prevent detrimental infections, as well as eliminating accumulated fluid with postural drainage and chest physiotherapy. Surgery may also be used to treat localized bronchiectasis, removing obstructions that could cause progression of the disease.
Inhaled steroid therapy that is consistently adhered to can reduce sputum production and decrease airway constriction over a period of time, and help prevent progression of bronchiectasis. One commonly used therapy is beclometasone dipropionate, which also used in asthma treatment. Use of inhalers such as albuterol (salbutamol), fluticasone (Flovent/Flixotide) and ipratropium (Atrovent) may help reduce likelihood of infection by clearing the airways and decreasing inflammation.
Mannitol dry inhalation powder, under the name Bronchitol, has been approved by the FDA for use in cystic fibrosis patients with or at risk for bronchiectasis. The original orphan drug indication approved in February 2005 allowed its use for the treatment of bronchiectasis. The original approval was based on the results of Phase II clinical studies showing the product to be safe, well-tolerated, and effective for stimulating mucus hydration/clearance, thereby improving quality of life in patients with chronic obstructive lung diseases like bronchiectasis. Long-term studies are underway as of 2007 to ensure the safety and effectiveness of the treatment.
Advair Diskus is also a commonly used inhaled corticosteroid which has in many cases been effective in clearing the airways, reducing sputum and reducing inflammation.
Rene Theophile Hyacinthe Laënnec, the man who invented the stethoscope, used his creation to first discover bronchiectasis in 1819. The disease was researched in greater detail by Sir William Osler in the late 1800s; in fact, it is suspected that Osler actually died of complications from undiagnosed bronchiectasis.
Causes:
There are both congenital and acquired causes of bronchiectasis. Kartagener syndrome, which affects the mobility of cilia in the lungs, aids in the development of the disease. Another common genetic cause is cystic fibrosis, in which a small number of patients develop severe localized bronchiectasis. Young's syndrome, which is clinically similar to cystic fibrosis, is thought to significantly contribute to the development of bronchiectasis. This is due to the occurrence of chronic, sinopulmonary infections. Patients with alpha 1-antitrypsin deficiency have been found to be particularly susceptible to bronchiectasis, for unknown reasons. Other less-common congenital causes include primary immunodeficiencies, due to the weakened or nonexistent immune system response to severe, recurrent infections that commonly affect the lung.
Acquired bronchiectasis occurs more frequently, with one of the biggest causes being tuberculosis. Endobronchial tuberculosis commonly leads to bronchiectasis, either from bronchial stenosis or secondary traction from fibrosis. A especially common cause of the disease in children is Acquired Immune Deficiency Syndrome (AIDS), stemming from the human immunodeficiency virus. This disease predisposes patients to a variety of pulmonary ailments, such as pneumonia and other opportunistic infection. Bronchiectasis can sometimes be an unusual complication of inflammatory bowel disease, especially ulcerative colitis. It can occur in Crohn's disease as well, but does so less frequently. Bronchiectasis in this situation usually stems from various allergic responses to inhaled fungus spores. Recent evidence has shown an increased risk of bronchiectasis in patients with rheumatoid arthritis who smoke. One study stated a tenfold increased prevalence of the disease in this cohort. Still, it is unclear as to whether or not cigarette smoke is a specific primary cause of bronchiectasis.
Other acquired causes of bronchiectasis involving environmental exposures include respiratory infections, obstructions, inhalation and aspiration of ammonia and other toxic gases, pulmonary aspiration, alcoholism, heroin (drug use), and various allergies.
Diagnosis:
The diagnosis of bronchiectasis is based on the review of clinical history and characteristic patterns in high-resolution CT scan findings. Such patterns include "tree-in-bud" abnormalities and cysts with definable borders. In one small study, CT findings of bronchiectasis and multiple small nodules were reported to have a sensitivity of 80%, specificity of 87%, and accuracy of 80% for the detection of bronchiectasis. Bronchiectasis may also be diagnosed without CT scan confirmation if clinical history clearly demonstrates frequent, respiratory infections, as well confirmation of an underlying problem via blood work and sputum culture samples.
Treatment:
Treatment of bronchiectasis is aimed at controlling infections and bronchial secretions, relieving airway obstruction, and preventing complications. This includes the prolonged usage of antibiotics to prevent detrimental infections, as well as eliminating accumulated fluid with postural drainage and chest physiotherapy. Surgery may also be used to treat localized bronchiectasis, removing obstructions that could cause progression of the disease.
Inhaled steroid therapy that is consistently adhered to can reduce sputum production and decrease airway constriction over a period of time, and help prevent progression of bronchiectasis. One commonly used therapy is beclometasone dipropionate, which also used in asthma treatment. Use of inhalers such as albuterol (salbutamol), fluticasone (Flovent/Flixotide) and ipratropium (Atrovent) may help reduce likelihood of infection by clearing the airways and decreasing inflammation.
Mannitol dry inhalation powder, under the name Bronchitol, has been approved by the FDA for use in cystic fibrosis patients with or at risk for bronchiectasis. The original orphan drug indication approved in February 2005 allowed its use for the treatment of bronchiectasis. The original approval was based on the results of Phase II clinical studies showing the product to be safe, well-tolerated, and effective for stimulating mucus hydration/clearance, thereby improving quality of life in patients with chronic obstructive lung diseases like bronchiectasis. Long-term studies are underway as of 2007 to ensure the safety and effectiveness of the treatment.
Advair Diskus is also a commonly used inhaled corticosteroid which has in many cases been effective in clearing the airways, reducing sputum and reducing inflammation.
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