[1] IRCCS Policlin San Matteo Fdn, Pneumol Unit, Pavia, PV, Italy
[2] Cincinnati Childrens Hosp, Translat Pulm Sci Ctr, Cincinnati, OH USA
[3] IRCCS Policlin San Matteo Fdn, Clin Epidemiol & Biometr Unit, Pavia, Italy
[4] IRCCS Policlin San Matteo Fdn, Anesthesiol & Intens Care Unit, Pavia, PV, Italy
[5] IRCCS Policlin San Matteo Fdn, Clin Chem Lab, Pavia, PV, Italy
[6] Univ Munich, Dr von Hauner Childrens Hosp, Munich, Germany
[7] Univ Pavia, IRCCS Policlin San Matteo Fdn, Pneumol Unit, Pavia, PV, Italy