A sweat test is a diagnostic procedure that uses a person's sweat as the sample for testing. Human sweat is excreted across the skin of the body. It is a method by which some toxins are passed out of the body. It is also used to regulate the fluids in the body. One of the primary functions of sweat is to offer cooling to the body. This happens through the process of evaporation. When we sweat, the sweat evaporates by consuming some of the heat energy from the skin and transforming into the gaseous form. This cools the skin and is one of the primary methods used by the human body to regulate its temperature. Human sweat contains many different components including salt. A sweat test is used to measure the level of salt, or sodium chloride. This test is used to diagnose the condition known as cystic fibrosis.
Cystic fibrosis is a condition that is inherited by an individual. It is a condition which affects the production of sweat and mucus in the body. Sweat is designed, as explained, for cooling while mucus is designed to capture infections and pass them out of the body. A person suffering from cystic fibrosis will have abnormally thick and sticky mucus. This makes the mucus ineffective, because, instead of passing the infection out, the mucus allows the infection to remain and grow within the area that is affected by it. This causes infections, particularly lung infections, to be more severe and is eventually fatal. The production of sweat is also affected to the extent where sweat becomes more salty than normal.
A positive sweat test is a test where an individual's sweat has a higher concentration of sodium chloride than normal. This is a strong indication for cystic fibrosis but is not a guarantee that the individual is suffering from the condition. There are a few other conditions that can cause increased salt levels in the sweat. These conditions include dehydration, malnutrition and hormonal problems. When there is some confusion, the doctor might order other tests to diagnose the condition of cystic fibrosis or to rule it out. For this reason, a person undergoing a sweat test must live as normal a life as possible prior to the test with normal food intake and a normal level of hydration. Cystic fibrosis can only be managed, it cannot be cured. Eventually, a patient with the condition will succumb to it.