[Value of neonatal screening for cystic fibrosis. Evaluation of a neonatal screening program including 34,522 neonates (author's transl)].

Screening for cystic fibrosis in 34,522 neonates was done by assaying proteolytic activity in feces samples spread on special filter paper. Infants were considered at high risk for cystic fibrosis if proteolytic activity was significantly decreased and albumin was found in all the fresh stool specimens. Cystic fibrosis was detected in eight infants, most of whom were already hospitalized for respiratory and/or digestive manifestations suggestive of the disease. Six other patients, one of whom was three-and-a-half years-old, were detected after referral by pediatricians. Two false-negative results were recorded, in infants without detectable pancreatic involvement. Given these results, the authors believe that routine neonatal screening for cystic fibrosis is unnecessary. The various etiopathogenetic mechanisms and the possibilities for investigating patients with cystic fibrosis are discussed.