The evaluation of a novel conductometric device for the diagnosis of cystic fibrosis.

Background: We evaluated the diagnostic discrimination of a new micro-flow cell device (Nanoduct) which measures sweat conductivity in situ at a regional referral centre for cystic fibrosis (CF).

Methods: The device was evaluated in comparison to the measurement of sweat chloride with the established quantitative pilocarpine iontophoresis test (QPIT) and extended in a number of patients to conductivity measurements in liquid sweat collected with the Macroduct system. Sweat testing was conducted simultaneously on patients referred for diagnostic sweat testing, on patients known to have CF and on adult volunteers.