Sweat Chloride Test

SWEAT CHLORIDE TEST

Sweat Chloride Test is essential for the diagnosis of cystic fibrosis (CF). Cystic fibrosis is a genetic disorder that affects the lungs and digestive system, leading to suppurative lung disease and other serious complications. Our state-of-the-art testing services help provide accurate diagnoses for children suspected of having cystic fibrosis.

What is the Sweat Chloride Test?

The Sweat Chloride Test is a key diagnostic procedure for cystic fibrosis. It measures the level of chloride (salt) in a child’s sweat. High levels of chloride in the sweat are indicative of cystic fibrosis, as the disorder affects the transport of salt in and out of cells. This test is non-invasive and is performed by stimulating sweat production, collecting the sweat, and analyzing the chloride content.

Why is the Sweat Chloride Test Important for Diagnosing Cystic Fibrosis?

Cystic fibrosis often presents with symptoms like persistent cough, difficulty breathing, and salty sweat. These symptoms may prompt the need for a sweat chloride test. A positive result, showing high chloride levels, is one of the most reliable indicators of cystic fibrosis. Early diagnosis is critical for managing suppurative lung disease, digestive issues, and other complications associated with CF.

What Role Does the Sweat Chloride Test Play in the Diagnosis of Cystic Fibrosis?

The sweat chloride test is considered the gold standard for diagnosing cystic fibrosis. If a child exhibits symptoms such as salty sweat, persistent respiratory infections, or poor growth, this test can help confirm the diagnosis. A sweat chloride level of over 60 millimoles per liter is typically considered a positive result for CF. Usually two positive sweat chloride test results are required to confirm the diagnosis.

How is Sweat Chloride test performed?

Sweat chloride test is done in the hospital and it does not require any admission. The sweat glands on the arm of the child are stimulated using electrical signals and some chemicals, then the area of the arm is wrapped and child is allowed to sweat for around 30 minutes. After 30 minutes, sweat is collected and sent for analysis in biochemistry lab.

Understanding results of Sweat Chloride Test

Children with cystic fibrosis have high chloride content than children who don’t have cystic fibrosis. To understand what the sweat test results mean, a chloride level of:

Less than or equal to 29 mmol/L = CF is unlikely regardless of age

Between 30 – 59 mmol/L = CF is possible and additional testing is needed

Greater than or equal to 60 mmol/L = CF is confrimed

When sweat chloride test results fall between the range of 30-59 mmol/L, the sweat test is usually repeated. If it remains intermediate the second time, genetic testing is advised.

Frequently Asked Questions

What is the Sweat Chloride Test used for?

The Sweat Chloride Test is primarily used for the diagnosis of cystic fibrosis by measuring the chloride levels in sweat, which are elevated in individuals with CF.

Why is salty sweat an indicator of cystic fibrosis?

People with cystic fibrosis have a defect in the CFTR gene, which results in excessive salt in their sweat. This leads to the characteristic salty sweat that is often noticed by parents and healthcare providers.

What is the connection between cystic fibrosis and suppurative lung disease?

Cystic fibrosis can lead to suppurative lung disease, where thick, sticky mucus builds up in the lungs, causing persistent infections and breathing difficulties. Early diagnosis through a sweat chloride test is crucial in managing these lung issues.

How accurate is the Sweat Chloride Test in diagnosing cystic fibrosis?

The sweat chloride test is considered the gold standard for diagnosing cystic fibrosis. A positive result, with chloride levels above 60 mmol/L, strongly suggests CF, although further genetic testing may be required in some cases.

Is the Sweat Chloride Test painful for children?

The Sweat Chloride Test is non-invasive and generally painless for children. It involves stimulating sweat production and collecting it for analysis, ensuring minimal discomfort during the procedure.