Sweat test

Sweat test is a diagnostic procedure used to measure the concentration of chloride in sweat. It is most commonly used to diagnose cystic fibrosis, a genetic disorder that affects the lungs and digestive system.

Procedure

The sweat test is a non-invasive procedure that involves stimulating sweat production on a small patch of skin on the arm or leg. This is usually done by applying a chemical called pilocarpine and then using a mild electrical current to promote sweat production. The sweat is then collected on a special paper or in a plastic coil and sent to a laboratory for analysis.

Interpretation

The results of a sweat test are usually available within a few days. A high level of chloride in the sweat is indicative of cystic fibrosis. However, a normal result does not necessarily rule out the disease, especially in newborns who may not produce enough sweat for the test.

Risks

The sweat test is generally considered safe. The electrical current used to stimulate sweat production can cause mild discomfort, but it is not harmful. There is also a small risk of skin irritation from the pilocarpine.

See also

• Cystic fibrosis
• Chloride
• Pilocarpine