Diagnosing CF

If your physician suspects you have cystic fibrosis, he/she will probably recommend a ‘sweat test’. Simple and painless, it measures the amount of salt in sweat. A high salt level, along with other symptoms, points to a diagnosis of cystic fibrosis.

Genetic tests are also being used to diagnose CF especially in adults, or when results of sweat tests are inconclusive. DNA from a cheek swab or blood sample is analyzed to look for mutations in the gene responsible for CF. Genetic tests are also used to diagnose CF prenatally.

Some provinces include cystic fibrosis as part of their newborn screening programs.

Approximately 60% of people with CF are diagnosed in the first year of life, and 90% by 10 years of age. For more information about a late diagnosis of CF visit Cystic Fibrosis Education.

Reviewed/updated: 2010-07-29