[1] S Raffaele Biomed Pk Fdn, Rome, Italy
[2] Univ Roma Tor Vergata, Dept Internal Med, I-00173 Rome, Italy
[3] Univ Chieti, Dept Paediat, Chieti, Italy
[4] Santa Chiara Hosp, Dept Paediat, Trento, Italy
[5] Giovanni XXIII Hosp, Dept Paediat, Bari, Italy
[6] Childrens Inst IRCCS Burlo Garofolo, Dept Paediat, Trieste, Italy
[7] IRCCS, Bambino Gesu Childrens Hosp, Rome, Italy
[8] IRCCS, Hosp S Raffaele, Dept Paediat, Milan, Italy
[9] Univ Modena, Dept Paediat, I-41100 Modena, Italy
[10] Univ Turin, Dept Paediat, I-10124 Turin, Italy
[11] Univ Naples 2, Dept Paediat, Naples, Italy