How much chloride is in a person’s sweat. People with CF have more chloride in their sweat. Measuring sweat chloride can help show if someone has CF .
Chloride is a component of salt. It is found in everyone’s sweat, but in people with cystic fibrosis the amount of chloride is usually much higher. Measuring sweat chloride levels can show if someone has cystic fibrosis. It is also used in some clinical trials to measure if a treatment increases CFTR function, which is usually reduced in cystic fibrosis.