When you breathe air is carried into your lungs through a series of branching tubes (called bronchi). The bronchi contain tiny glands that produce a small amount of mucus. This helps to keep your tubes moist and traps the dust and germs that you breathe in. The mucus is then normally moved away by tiny hairs (called cilia) which line the tubes.
When your bronchial tubes get damaged, they cannot clean themselves. Mucus builds up, spilling over into other tubes. These tubes are then more likely to be infected by bacteria. This causes inflammation and leads to damage called 'bronchiectasis'. The result is a cycle of repeated lung infections and blocked airways.
Three types of bronchiectasis exist:
Cylindrical – Slight widening of the respiratory passages. This is the most common form of bronchiectasis and can be reversed.
Varicose – Broncial walls have both extended and collapsed portions.
Cystic – An irreversible ballooning of the bronchi. This the most severe form of bronchiectasis.
In addition bronchiectasis can be further complicated by emphysema and bronchitis.