 [ Symptoms ] dry itchy patches on my face need second doctor opinion [ Disease ] cystic fibrosis cf is a chronic progressive condition that affects the body is respiratory and digestive systems it is due to a gene defect people who have cf produce abnormally thick sticky mucus which clogs the lungs and leads to repeated lung and sinus infections as well as difficulty breathing the thick mucus also obstructs the ducts of the pancreas preventing digestive enzymes from reaching the intestines because so little food is absorbed children with cf have difficulty gaining and maintaining weight cf also affects the reproductive systems of both males and females females with cf may have difficulty getting pregnant males with cf are almost always sterile because they produce relatively few or no sperm