Cystic fibrosis screening in the newborn [editorial].

Many attempts have been made to establish a suitable screening test for 
cystic fibrosis for newborns. Recently, a new method has been described 
by Crossley and her associates. It is based on measuring pancreatic 
trypsin in a sample of faeces collected on to filter paper 
on the 4th or 5th day of life. The false-negative rate 
of the new test has not yet been determined, but older 
children with CF and pancreatic achylia all gave abnormal results when 
tested. The disadvantage of the test, as with the meconium albumin 
test, is that about 10% of children with CF are said 
not to have pancreatic achylia. Whilst the method needs more extensive 
evaluation, it appears technically more satisfactory than others so far described. 
