[Current use of the sweat test (author's transl)].

A positive sweat test is still the principal diagnostic feature of cystic fibrosis. Repeated tests are mandatory in positive, borderline and any suspect cases. Pilocarpine iontophoresis and quantitative evaluation of sodium and/or chloride are the only acceptable test methods. Every effort must be made to avoid contamination of the sweat sample. Diagnostic values are more than 50 mequ/l for sodium and more than 60 mequ/l for chloride.