False negatives in the newborn screening for cystic fibrosis in Western Andalusia: Results from a 10-year experience.

Cystic fibrosis (CF) is the most common autosomal recessive disorder in the Caucasian population, with an incidence of 1:5000 live births. In 2011, the screening of CF was implemented in the Andalusian Public Health newborn screening program by using immunoreactive trypsinogen and chloride sweat test (IRT/IRT/sweat test) determinations. Since then, 79 children have been diagnosed with CF in our health area (Western Andalusia).