Damaged airways
Bronchiectasis is a condition in which the lungs airways become abnormally winded and allow the building up of mucus, making the lungs more prone to infection. Cystic fibrosis is one of the most leading causes of bronchiectasis, a chronic lung condition with abnormal widening and airways scarring. When the whole area of lungs and airways is blocked due to mucus and infection, it makes it extremely hard to breathe more air in and out of the lungs and clear mucus from bronchial tubes leading to bronchitis. It also leads to a persistent cough that brings up phlegm.