Damage to the walls of the airways usually is the cause of bronchiectasis. A lung infection may cause this damage. Examples of lung infections that can lead to bronchiectasis include:
- Severe pneumonia (nu-MO-ne-ah)
- Whooping cough or measles (uncommon in the United States due to vaccination)
- Fungal infections
Conditions that damage the airways and raise the risk of lung infections also can lead to bronchiectasis. Examples of such conditions include:
- Cystic fibrosis. This disease leads to almost half of the cases of bronchiectasis in the United States.
- Immunodeficiency disorders, such as common variable immunodeficiency and, less often, HIV and AIDS.
- Allergic bronchopulmonary aspergillosis (AS-per-ji-LO-sis). This is an allergic reaction to a fungus called aspergillus. The reaction causes swelling in the airways.
- Disorders that affect cilia (SIL-e-ah) function, such as primary ciliary dyskinesia. Cilia are small, hair-like structures that line your airways. They help clear mucus (a slimy substance) out of your airways.
- Chronic (ongoing) pulmonary aspiration (as-pih-RA-shun). This is a condition in which you inhale food, liquids, saliva, or vomited stomach contents into your lungs. Aspiration can inflame the airways, which can lead to bronchiectasis.
- Connective tissue diseases, such as rheumatoid arthritis, Sjögren’s syndrome, and Crohn’s disease.
Other conditions, such as an airway blockage, also can lead to bronchiectasis. Many things can cause a blockage, such as a growth or a noncancerous tumor. An inhaled object, such as a piece of a toy or a peanut that you inhaled as a child, also can cause an airway blockage.
A problem with how the lungs form in a fetus may cause congenital bronchiectasis. This condition affects infants and children.