What is Cystic Fibrosis?
by Peggy Deland
What is Cystic Fibrosis?
Cystic fibrosis is an inherited condition that causes problems with the lungs and other organs. It is uncommon; approximately 30,000 people in the United States have this condition. Caucasians are more likely to be affected than other races. Some people carry the gene without exhibiting symptoms.
Cystic fibrosis is an abnormality in the cells that produces mucus, saliva, digestive juices and sweat. Mucus is thick and clogs the airways and other passages in the body, while sweat contains large amounts of salt. The digestive system is unable to draw sufficient nutrients from food. Symptoms include frequent respiratory infections, bulky stools, difficulty maintaining or gaining weight, salty-tasting skin and clubbing of the fingers and toes.
The most commonly used method to diagnose cystic fibrosis is the sweat test. A small amount of a chemical that encourages sweat production is applied to the skin. The area is then stimulated with a weak electrical current, causing sweat production. The sweat is then collected and sent to a laboratory for analysis. An abnormal level of salt in the sweat indicates that the person most likely has cystic fibrosis. Genetic analysis is sometimes done to confirm the diagnosis or to test for cystic fibrosis in very young children who cannot produce sufficient sweat for testing.
There is no cure for cystic fibrosis, but several treatments have been developed that reduce the damage done by the condition and improve the patient's quality of life. Most of the drugs used to treat cystic fibrosis are inhaled using a nebulizer. These aerosolized medications include antibiotics that reduce the frequency of infection, enzymes that thin mucus in the lungs and bronchodilators. Other medications are taken as tablets or capsules, including pancreatic enzymes to assist in digestion of food, supplemental vitamins to replace those that are not sufficiently absorbed and non-steroidal anti-inflammatory drugs, such as ibuprofen, to reduce inflammation. Airway-clearing techniques are also an important part of cystic fibrosis treatment as they loosen mucus in the lungs.
Cystic fibrosis is caused by a defective gene. If a person has two defective copies of the gene, they have cystic fibrosis. If they only have one copy, they are a carrier. When two carriers have a child, there is a 25 percent chance the child will have cystic fibrosis, a 50 percent chance the child will be a carrier, and a 25 percent chance the child will not have the defective gene at all. Screening tests are available to test prospective parents for the defective genes that cause cystic fibrosis, and to test unborn children for the condition.
Cystic fibrosis is life-threatening; on average, people who have the condition live for 37 years. However, the survival rate of cystic fibrosis patients has increased drastically over the last 20 years and continues to increase due to improved treatments. Research continues in the search for a cure and is primarily focused on finding a method to replace the damaged genes, particularly in the airways. One technique that shows promise uses modified viruses to deliver normal copies of the genes into the lungs.