Bronchiectasis is an abnormal, chronic enlargement of the bronchi, the passageways from the trachea to the alveoli that are the air-exchanging parts of the lungs.
Bronchiectasis generally occurs as a result of infection, although noninfectious factors may contribute to the development of this condition. Accompanying the enlargement of the bronchi is their decreased ability to clear secretions.
Failure to clear secretions allows microbes and particles to collect in them, which leads to more secretions and inflammation that further damage the airways, causing more dilation in a vicious cycle.
