Testing for Cystic Fibrosis

How can you know for sure if you or your child has cystic fibrosis? If someone in your family has the disease, could you pass it down to your children?

There are several ways to help answer these important questions.

Genetic Carrier Testing -- More than 10 million Americans are symptomless carriers of the defective CF gene. This test can help detect carriers, who could pass CF onto their children. To have cystic fibrosis, a child must inherit one copy of the defective CF gene from each parent.

Each time two carriers of the CF gene have a child, the chances are:

• 25% the child will have CF;
• 50% the child will carry the CF gene but not have CF; and
• 25% the child will not carry the gene and not have CF.

Newborn Screening -- Newborns screened for cystic fibrosis can benefit from early diagnosis and treatment, which can:

• Improve growth;
• Improve lung function;
• Reduce hospital stays; and
• Add years to life.

While newborn screening is not a definitive diagnostic test for cystic fibrosis, it may lead to tests that can rule out or confirm a CF diagnosis. The Cystic Fibrosis Foundation and the Centers for Disease Control and Prevention recommend screening for cystic fibrosis for all newborns.

Sweat Test -- If a person exhibits symptoms of CF, a doctor may order a sweat test. This simple, painless test is the best way to diagnose CF. It measures the concentration of salt in a person's sweat. A high salt level indicates CF.

Sweat tests should be done at a Cystic Fibrosis Foundation-accredited care center where strict guidelines help ensure accurate results.

For more information:

• To explore all aspects of living with CF at every stage of life, visitLIVING WITH CYSTIC FIBROSIS.
• See whatTREATMENTSare available and what's in development.