What is Cystic Fibrosis?
Cystic fibrosis (CF) is the most common fatal genetic disease affecting Canadian children and young adults. There is no cure.
Cystic fibrosis causes various effects on the body, but mainly affects the digestive system and lungs. The degree of cystic fibrosis involvement differs from person to person. However, the persistence and ongoing infection in the lungs, with destruction of lungs and loss of lung function, eventually causes death in the majority of people who have cystic fibrosis.
Typical complications caused by cystic fibrosis are difficulty in digesting fats and proteins; vitamin deficiencies due to loss of pancreatic enzymes; and progressive loss of lung function.
It is estimated that one in every 3,600 children born in Canada has cystic fibrosis. Almost 4,000 Canadian children, adolescents, and adults with cystic fibrosis attend specialized CF clinics.
For more information about disease management, please visit Living with Cystic Fibrosis.
Causes of Cystic Fibrosis
Cystic fibrosis is a genetic disease that occurs when a child inherits two abnormal genes, one from each parent. Approximately, one in 25 Canadians carry an abnormal version of the gene responsible for cystic fibrosis. Carriers do not have cystic fibrosis, nor do they exhibit any of the symptoms of the disease.
When two parents who are carriers have a child, there is a 25 percent chance that the child will be born with cystic fibrosis; there is also a 50 percent chance that the child will be a carrier; and a 25 percent chance that the child will neither be a carrier nor have cystic fibrosis.
Symptoms of Cystic Fibrosis
Cystic fibrosis is a multi-system disorder that produces a variety of symptoms including:
- Persistent cough with productive thick mucous
- Wheezing and shortness of breath
- Frequent chest infections, which may include pneumonia
- Bowel disturbances, such as intestinal obstruction or frequent, oily stools
- Weight loss or failure to gain weight despite possible increased appetite
- Salty tasting sweat
- Infertility (men) and decreased fertility (women)
Diagnosing Cystic Fibrosis
If a doctor suspects a patient has cystic fibrosis, a ‘sweat test’ may be administered. This simple and painless test measures the amount of salt content present in sweat. If the test comes back positive, it means the sweat content collected contains more salt than usual and validates a diagnosis of cystic fibrosis. In addition, a test for the presence of enzymes in the intestine can be performed.
Genetic testing, prenatal and newborn screening are other methods of determining the presence of cystic fibrosis. These are relatively simple, non-invasive tests.