Cystic fibrosis is an inherited disease of the mucus glands. It causes chronic, progressive damage to the respiratory system, chronic digestive system problems, and can affect other organs.

The signs and symptoms of this disorder are caused by the production of abnormally thick, sticky mucus in the body's organs. Problems with breathing are among the most serious symptoms. Mucus can obstruct the airways and cause bacterial infections in the lungs, leading to chronic coughing, wheezing, and inflammation. Over time, mucus buildup and infections lead to permanent lung damage, including the formation of scar tissue (fibrosis) and cysts in the lungs.

Most people with cystic fibrosis also have digestive problems. Mucus can block the ducts of the pancreas, preventing enzymes produced by that organ from reaching the intestines to help digest food. Problems with digestion can lead to diarrhea, malnutrition, and weight loss. Some babies with cystic fibrosis have meconiumileus, a blockage of the intestine that occurs shortly after birth.

Infertility, or the inability to conceive a child, is common in men with cystic fibrosis, but infrequent in women with the condition.