In August 1989, Canadian scientists discovered the `normal' gene, when defective, causes CF. Certain cells in the child's body produce a protein that doesn't function as it should when the child has CF. It impairs the movement of salts and fluids across the membranes of affected cells. This defect produces the characteristic symptoms, namely, accumulation of thick, dry mucus in the lungs and blocked pancreatic ducts.
Cystic fibrosis is an incurable genetic disease, occuring when a child inherits a copy of the defective CF gene from each parent, and it affects mainly the lungs and digestive system. In the lungs, the most devastating site for CF to strike, increasingly severe respiratory problems occur, often causing an early death for most of its victims. In the digestive tract, CF there is often an extreme difficulty in digesting adequate nutrients from food.
Normal mucus is thin and slippery, helping to keep the lungs and air passages clean by filtering out germs and dust particles. In children with CF, sticky mucus clogs the small bronchial tubes in the lungs, causing difficulty in breathing. Air gets trapped in some of these tubes, and parts of the lungs may be blocked off by mucus. Bacteria collect in the clogged bronchial tubes and multiply, causing infection. Similarly, mucus plugs the tiny ducts of the pancreas, an organ lying near the intestine, just below the stomach. The pancreas supplies the small intestine with enzymes to assist in digestion. When the openings from the pancreas are blocked by mucus, the enzymes cannot reach the small intestine. As a result, the food that passes through the bowels is not fully digested, and nutritional value is lost.
Symptoms of CF usually appear early in life. In some children it is the lungs that are mainly affected, while in others, the digestive system, or many have both problems. Parents often indicate the first symptom as the infant's skin tastes salty when kissed. As a result of many body systems that can be involved, Cystic fibrosis is associated with a variety of symptoms. These can include:
· a persistent cough which sometimes sounds like whooping cough. It may interfere with the child's sleep and feeding, and vomiting may occur after a bout of coughing
