Cystic Fibrosis is an inherited disease that causes mucus to be thick. It affects sinuses, lungs, sweat glands, pancreas, liver, intestines, and fertility. The lungs can get clogged with mucus, causing difficulty breathing and making the right environment for bacteria to grow. Patients may have steatorrhea (frothy, foul-smelling stool that floats because of a high fat content) and grotesque breath usually due to infections in the lungs and sinuses or due to improper digestion.