[1] Univ Hosp Zurich, Dept Pulmonol, Zurich, Switzerland
[2] Univ Childrens Hosp, Connect Tissue Unit, Div Metab, Zurich, Switzerland
[3] Univ Childrens Hosp, Childrens Res Ctr, Zurich, Switzerland
[4] Univ Childrens Hosp Zurich, Div Resp Med, Zurich, Switzerland