17 Cystic fibrosis newborn screening (CF NBS): 4 year experience of the Prague Centre with the IRT/DNA/IRT protocol

Background: Cystic Fibrosis Newborn screening (CFNBS) as a pilot study started at the Institute of Mother and Child (IMC) Centre in 1999 and 444 063 newborns were examined until 2003. Current CFNBS has started gradually in Poland in 2006, covering the whole country in 2009 and is ongoing. 582 693 children were screened until the end of 2011. During CFNBS different protocol’s strategies were used. Aim: Impact of the implementation of NBS on the age of CF diagnosis. Methods: The study involved children diagnosed and treated only in IMC CF Centre (from 1999 until the end of 2011). Three groups were formed: 1. Pilot group (p-NBS) − 56 children, according to protocol strategy IRT/IRT and IRT/IRT/DNA, only F508del mutation was assessed; 2. Current group (c-NBS) − 92 children, IRT/IRT/DNA and IRT/DNA protocol, with expanded DNA analysis panel; 3. Patient diagnosed clinically (non-NBS) − 56 children. Moreover, DNA analysis in c-NBS group contains also frequent mutation in Polish population: 3849+10kbC>T, which is combined with low sweat test values. All patients underwent sweat tests. Results: The age of diagnosis was significantly lower (both p T than p-NBS and non-NBS group (both 0.9%). Conclusion: IRT/DNA strategy with extended DNA analysis provides an opportunity of earlier CF diagnosis even in children with normal sweat test values.