[1] Hadassah Univ Hosp, Dept Pediat, IL-91120 Jerusalem, Israel
[2] Hadassah Univ Hosp, CF Ctr, IL-91120 Jerusalem, Israel
[3] St James Univ Hosp, Paediat Ctr, Leeds LS9 7TF, W Yorkshire, England
[4] St James Univ Hosp, Adult Reg Cyst Fibrosis Ctr, Leeds LS9 7TF, W Yorkshire, England
[5] Seacroft Univ Hosp, Paediat Ctr, Leeds, W Yorkshire, England
[6] Seacroft Univ Hosp, Adult Reg Cyst Fibrosis Ctr, Leeds, W Yorkshire, England