B62-12 The Importance of Consistency in Sweat Testing

Sweat testing is the gold standard for diagnosis of cystic fibrosis. The Cystic Fibrosis Foundation (CFF) has very high expectations for maintaining high levels of success rates in obtaining sweat for analysis. Quantity Not Sufficient (QNS) results are to remain at a low standard set by the CFF, with primary focus on maintaining a QNS rate lower than 10% for patients less than one month of age. During a routine site visit from the CFF, it was found that the QNS rate was higher than desired at our CF Center. It was also discovered that the number of laboratory technicians running the analysis of the sweat was nearly quadruple the acceptable number, having 20+ technicians trained to run the samples when a center our size should have only 5-7 technicians running the sweat chloride analysis. We worked with the lab director and limited the number of lab employees performing the analysis in hopes to improve the QNS rates. This limited our availability of analyses to be ran daily because the analyzer would now only be operated between the hours of 7am-2:20pm. After quarter 2 results came back in 2025, comparatively to all of 2024 and Q1 of 2025, the QNS rates were immediately improved; in patients less than 3 months of age, the QNS rate dropped from 25% in Q1 of 2025 to 0% in Q2 of 2025. It also must be noted that the system used for sweat induction was updated in early 2025 but during the initiation process showed no real difference in the ability to collect sweat. The quarterly evaluations of QNS rates continue to be calculated to build on this research and quality improvement initiative.