NCFBE is a disease of the lungs, where the airways (called the bronchi and bronchioles) become enlarged (widen) and this may make breathing more difficult.
It can be caused by an infection or another condition – sometimes the cause is not known. In those with NCFBE, the body’s defence system (immune system) overreacts to a foreign substance in the airways (e.g. an infection with a bacteria or virus) and causes permanent damage to the tissues surrounding the airways, causing them to widen.
This makes it more likely that the person with NCFBE will suffer from more infections. Each infection leads to further reactions from the immune system and could cause damage to the lungs.