What is Cystic Fibrosis

Cystic fibrosis (CF) (pronounced: sis -tik fy- bro -sus) is the most common inherited disease. CF is a genetic disorder that particularly affects the lungs and digestive system and makes a child more vulnerable to repeated lung infections. A defective gene causes the body to produce an abnormally thick, sticky mucus that clogs the lungs and leads to life-threatening lung infections. These thick secretions also obstruct the pancreas, preventing digestive enzymes from reaching the intestines to help break down and absorb food.

The mucus in people with CF is thicker than normal because CF affects cells in the epithelium (pronounced: eh-puh- thee -lee-um), the layer of cells that lines the passages in the body's organs. In a person who does not have CF, the epithelial cells produce a thin, watery mucus that acts like a lubricant and helps protect the body's tissues. In a person with CF, however, the thicker mucus doesn't move as easily. This thick, sticky mucus clogs passages in many of the body's organs.

The two organs that are most affected are the lungs and pancreas , where the thick mucus causes breathing and digestive problems. The thicker mucus has trouble moving out of the lungs, so bacteria can remain and cause infections. The thick mucus can also be found in the pancreas - an organ that produces proteins called enzymes that flow into the intestine to support the body's digestion process. Because the mucus can block the path between the pancreas and the intestines, people with CF have trouble digesting food and getting the vitamins and nutrients they need from it.

CF can also affect the liver, the sweat glands, and the reproductive organs.