From About Cystic Fibrosis at Cystic Fibrosis Foundation website:
What is Cystic Fibrosis?
Cystic fibrosis is a life-threatening, genetic disease that causes persistent lung infections and progressively limits the ability to breathe.
In people with CF, a defective gene causes a thick, buildup of mucus in the lungs, pancreas and other organs. In the lungs, the mucus clogs the airways and traps bacteria leading to infections, extensive lung damage and eventually, respiratory failure. In the pancreas, the mucus prevents the release of digestive enzymes that allow the body to break down food and absorb vital nutrients.
Read More info on the CFF.ORG HERE