Cystic Fibrosis Diagnosis
In order for your doctor to make a cystic fibrosis diagnosis, he or she will need to obtain a detailed medical and family history, perform a thorough physical examination, and order tests. The test that is most useful for making a cystic fibrosis diagnosis is the sweat test. This test measures the amount of salt in your sweat; high levels of salt in the sweat generally indicate cystic fibrosis.
An Overview of Cystic Fibrosis Diagnosis
- Obtain a detailed medical and family history
- Perform a thorough physical examination
- Order tests to ensure an accurate diagnosis.
Cystic Fibrosis Diagnosis and the Sweat Test
The sweat test is the most useful test for making a cystic fibrosis (CF) diagnosis. A sweat test measures the amount of salt in your sweat. To perform this test, your doctor will follow this process:
- First, your doctor will rub a small amount of a chemical called pilocarpine on your arm or leg.
- Then your doctor will attach an electrode to this spot. The electrode provides a mild electric current that produces sweat. This may cause tingling or a feeling of warmth.
- Then your doctor will cover the area with a gauze pad or filter paper and wrap it in plastic.
- After 30 to 40 minutes, your doctor will remove the plastic so that the sweat that collected on the pad or paper can be analyzed.
The test is usually performed twice. High levels of salt would mean that you have cystic fibrosis.
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD