Bronchiectasis can arise from infectious or noninfectious causes 

Major Etiologies of Bronchiectasis and Proposed Workup

Pattern of Lung Involvement Etiology by Category (Examples) Workup
Focal Obstruction (aspirated foreign body, tumor mass) Chest imaging (chest x-ray and/or chest CT); bronchoscopy
Diffuse Infection (bacterial, nontuberculous mycobacterial) Sputum Gram’s stain/culture; stains/cultures for acid-fast bacilli and fungi. If no pathogen is identified, consider bronchoscopy with bronchoalveolar lavage.
Immunodeficiency (hypogammaglobulinemia, HIV infection, bronchiolitis obliterans after lung transplantation) Complete blood count with differential; immunoglobulin measurement; HIV testing
Genetic causes (cystic fibrosis, Kartagener’s syndrome, α1 antitrypsin deficiency) Measurement of chloride levels in sweat (for cystic fibrosis), α1 antitrypsin levels; nasal or respiratory tract brush/biopsy (for dyskinetic/immotile cilia syndrome); genetic testing
Autoimmune or rheumatologic causes (rheumatoid arthritis, Sjögren’s syndrome, inflammatory bowel disease); immune-mediated disease (allergic bronchopulmonary aspergillosis) Clinical examination with careful joint exam, serologic testing (e.g., for rheumatoid factor). Consider workup for allergic bronchopulmonary aspergillosis, especially in patients with refractory asthma.a
Recurrent aspiration Test of swallowing function and general neuromuscular strength
Miscellaneous (yellow nail syndrome, traction bronchiectasis from postradiation fibrosis or idiopathic pulmonary fibrosis) Guided by clinical condition
Idiopathic Exclusion of other causes

aSkin testing for Aspergillus reactivity; measurement of serum precipitins for Aspergillus, serum IgE levels, serum eosinophils, etc.



Clues to the underlying etiology are often provided by the pattern of lung involvement. Focal bronchiectasis refers to bronchiectatic changes in a localized area of the lung and can be a consequence of obstruction of the airway—either extrinsic (e.g., due to compression by adjacent lymphadenopathy or parenchymal tumor mass) or intrinsic (e.g., due to an airway tumor or aspirated foreign body, a scarred/stenotic airway, or bronchial atresia from congenital underdevelopment of the airway). Diffuse bronchiectasis is characterized by widespread bronchiectatic changes throughout the lung and often arises from an underlying systemic or infectious disease process.1


The initial airway damage that leads to bronchiectasis often begins in childhood. However, signs and symptoms may not appear until months or even years after you start having repeated lung infections.



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.


Figure A shows a cross-section of the lungs with normal airways and with widened airways. Figure B shows a cross-section of a normal airway. Figure C shows a cross-section of an airway with bronchiectasis.


Bronchiectasis can affect just one section of one of your lungs or many sections of both lungs.

The initial lung damage that leads to bronchiectasis often begins in childhood. However, symptoms may not occur until months or even years after you start having repeated lung infections.

In the United States, common childhood infections—such as whooping cough and measles—used to cause many cases of bronchiectasis. However, these causes are now less common because of vaccines and antibiotics.

Now bronchiectasis usually is due to a medical condition that injures the airway walls or prevents the airways from clearing mucus. Examples of such conditions include cystic fibrosis and primary ciliary (SIL-e-ar-e) dyskinesia (dis-kih-NE-ze-ah), or PCD.

Bronchiectasis that affects only one part of the lung may be caused by a blockage rather than a medical condition.

Bronchiectasis can be congenital (kon-JEN-ih-tal) or acquired. Congenital bronchiectasis affects infants and children. It's the result of a problem with how the lungs form in a fetus.

Acquired bronchiectasis occurs as a result of another condition or factor. This type of bronchiectasis can affect adults and older children. Acquired bronchiectasis is more common than the congenital type.


Currently, bronchiectasis has no cure. However, with proper care, most people who have it can enjoy a good quality of life.

Early diagnosis and treatment of bronchiectasis are important. The sooner your doctor starts treating bronchiectasis and any underlying conditions, the better your chances of preventing further lung damage.









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