[1] United Hosp, Dept Gastroenterol & Transplantat, Cyst Fibrosis Ctr, Ancona, Italy
[2] Univ Liverpool, Dept Womens & Childrens Hlth, Liverpool, England
[3] Childrens Hosp Eastern Switzerland, St Gallen, Switzerland
[4] Univ Hosp Leuven, Dept Pediat, CF Ctr, Leuven, Belgium
[5] Paris Ctr Univ, Necker Enfants Malades Hosp, AP HP, CF Ctr, Paris, France
[6] Hadassah Hebrew Univ, Med Ctr, Jerusalem, Israel
[7] Paris Ctr Univ, Necker Enfants Malades Hosp, AP HP, Labs Biochem & Reg Newborn Screening, Paris, France
[8] Clin Hosp Ctr Rijeka, Clin Dept, Lab Diagnost, Rijeka, Croatia
[9] Royal Brompton Hosp, Adult Cyst Fibrosis Ctr, London, England
[10] Imperial Coll, London, England
[11] Univ Ziekenhuis Brussel, Vrije Univ Brussel, CF Ctr, Brussels, Belgium