The primary aim of the study is to determine if the CF Quantum Sweat Test provides sweat chloride results that are equivalent to the results from traditional sweat testing. The secondary aim of the study is to assess the quantity not sufficient rate of the CF Quantum Sweat Test compared to traditional sweat testing.

All 50 states and the District of Columbia are performing newborn screening for cystic fibrosis (CF). Infants who have a positive newborn screen require follow-up with a sweat test. Gibson-Cooke Quantitative Pilocarpine Iontophoresis (GCQPIT) requires collecting sweat in microbore tubing or on gauze/filter paper and analyzing sweat using a chloridometer. This test has many difficulties including specimens that are quantity not sufficient (QNS), many steps of pipetting solutions in the laboratory, and the need for a chloridometer to analyze sweat chloride concentration. The only manufacturer of a chloridometer has ceased production of this instrument. The CF Quantum® Sweat Test System (CFQT) overcomes all of the difficulties of GCQPIT. This pilot study will determine if the CFQT provides results that are equivalent to GCQPIT.

Inclusion Criteria:

• clinical diagnosis of cystic fibrosis
• patients who require a sweat test

Exclusion Criteria:

• Infants less than 48 hours of age
• Patient is receiving oxygen by open delivery
• collection site has diffuse inflammation or rash

pediatric pulmonology clinic