The page below is a sample from the LabCE course Laboratory Diagnosis of Cystic Fibrosis. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about Laboratory Diagnosis of Cystic Fibrosis (online CE course) »
How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 97 CE courses, most popular
$95 Add to cart
Pick Your Courses
Up to 8 CE hours
$50 Add to cart
Individual course$20 Add to cart

Quantitative Sweat Analysis

A quantitative sweat chloride test is required to confirm the diagnosis of CF. This test is referred to as the quantitative pilocarpine iontophoresis test (QPIT). The QPIT involves quantitating both the amount of sweat collected as well as the chloride concentration from either gauze/filter paper pads or Macroduct® coil. Generally, chloride concentration is determined by coulometric titration with a chloridometer (see image on the right). Automated analyzers used for serum or urine chloride may not possess sufficient sensitivity for detecting the lower concentrations of chloride found in sweat. The lower limit of the analytical measurement range for sweat chloride should be less than or equal to 10 mmol/L on unadulterated sweat.