Sweat testing infants detected by cystic fibrosis newborn screening.
OBJECTIVE
Describe and define limitations of early pilocarpine iontophoresis (sweat testing) for cystic fibrosis (CF) newborn screening (NBS).


METHODS
Population-based results from follow-up of CF NBS-positive newborns.


RESULTS
Insufficient quantity of sweat is more likely if the sweat test is done too early, but testing is generally successful after 2 weeks of age. Sweat chloride levels drop over the first weeks of life. CF carriers have higher sweat chloride concentrations than non-carriers.


CONCLUSIONS
Sweat testing can be performed effectively after 2 weeks of age for CF NBS-positive newborns. Earlier testing has a higher risk of insufficient sweat for completing testing.
Parad
Richard B
RB
New England Newborn Screening Program of University of Massachusetts Medical School, MA 02130, USA. richard.parad@umassmed.edu
Comeau
Anne Marie
AM
Dorkin
Henry L
HL
Dovey
Mark
M
Gerstle
Robert
R
Martin
Thomas
T
O'Sullivan
Brian P
BP
D000367:Age Factors; D000465:Algorithms; D002712:Chlorides / Q000032:analysis*; D003550:Cystic Fibrosis / Q000175:diagnosis* / Q000235:genetics; D004252:DNA Mutational Analysis; D003663:Decision Trees; D042241:Early Diagnosis; D005188:False Negative Reactions; D005189:False Positive Reactions; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D007478:Iontophoresis / Q000379:methods* / Q000592:standards; D016014:Linear Models; D008404:Massachusetts; D018721:Muscarinic Agonists; D015997:Neonatal Screening / Q000379:methods* / Q000592:standards; D018579:Patient Selection; D010862:Pilocarpine; D012016:Reference Values; D012017:Referral and Consultation; D012307:Risk Factors; D013542:Sweat / Q000737:chemistry*
D002712:Chlorides; D018721:Muscarinic Agonists; D010862:Pilocarpine