title: Interpretation of sweat sodium results--the effect of patient age.
abstract: In a retrospective study of sweat tests performed on 650 patients, sweat sodium was shown to increase with age in children without cystic fibrosis. The clearest separation of children with and without cystic fibrosis was in the youngest infants, while the highest proportion of repeatedly equivocal results was in the older children. Applying age-related reference ranges did not resolve the equivocal cases without also missing some cases of cystic fibrosis.
authors.affiliation: Department of Paediatric Biochemistry, Royal Hospital for Sick Children, Edinburgh, UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Kirk
authors.forename: A
authors.initials: A
authors.lastname: Westwood
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000175:diagnosis*; D005188:False Negative Reactions; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007478:Iontophoresis; D012016:Reference Values; D012964:Sodium / Q000032:analysis*; D013542:Sweat / Q000032:analysis*
chemical_list: D012964:Sodium