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About CF » Pathophysiology of CF » Sweat gland

Sweat gland

At first glance, it would seem that the sweat glands of CF sufferers do not seem to be abnormal — there are no obstructions to ducts and sweat is readily produced. However, people with CF produce sweat containing elevated amounts of salt.

This hallmark sign is used to reliably diagnose up to 98% of individuals with CF.1 Moreover, evidence suggests that the level of sweat chloride correlates with disease severity. For example, sufferers with ‘mild’ CF tend to have lower sweat chloride levels than those with pancreatic insufficiency.2

Sweat gland table

Correlation between CFTR activity and CF symptoms. Modified from Mishra et al.1


Sweat chloride levels

Find out how CF modifies sweat chloride levels.

  1. Mishra A et al. Clin Biochem Rev 2005;26:135–53
  2. Farrell PM et al. J Pediatr 2008;153:S4–14