Newborn Cystic Fibrosis Declining in Massachusetts
A letter in the latest issue of the NEJM indicates that the number of neonates identified with cystic fibrosis (CF) through neonatal screening declined substantially during the 4-year period from 2003 to 2006 in Massachusetts and was associated with a significant decrease in the number of infants with the most common CF-related genotype, ∆F508/∆F508.
The authors, from the New England Newborn Screening Program, observed an expected number of infants with CF from 1999 to 2002; however, in 2003, infants identified with the ∆F508/∆F508 genotype declined significantly, and this decline was maintained during the next 4 years.
The authors conjecture that the gradual uptake of preconception and prenatal screening to identify CF carriers among the general population since 2001 has resulted in fewer births of children with recognized CF-related genotypes. But they advise that the reduced incidence of known CF genotypes will lower the predictive value of newborn screening for CF.