Sweat Testing in Ireland

Introduction Quick, painless, cheap and reliable, the sweat test remains the gold standard diagnostic test for cystic fibrosis. We aimed to describe the pattern of testing in Ireland over a calendar year. Methods Information on sweat test practices was requested from each centre between 1st January 2011 and 31st December 2011, and the number of positive, negative, equivocal, and insufficient samples was recorded. Results In 2011 there were 2555 sweat tests performed in 15 centres, ranging from 35 to over 450 tests per centre. 35 (1.4%) were in the diagnostic range. The overall quantity not sufficient (QNS) rate was 10.3% (range 0-28.3%). Testing was performed across a wide age range (2.5 weeks to 75 years). The mean sweat chloride value was 16.5 mmol/L (SD 16.1 mmol/L). Discussion Our study demonstrates a high number of sweat tests performed in Ireland with significant variation in sweat testing practices across 15 different sites.