[1] G Gaslini Childrens Hosp, Epidemiol & Biostat Sect, Sci Directorate, I-16147 Genoa, Italy
[2] Univ Padua, Clin Pediat Hematol & Oncol, Padua, Italy
[3] Regina Margherita S Anna Children Hosp, Turin, Italy
[4] Bambino Gesu Pediat Hosp, Rome, Italy
[5] Meyer Children Hosp, Florence, Italy
[6] Burlo Garofalo Children Hosp, Trieste, Italy
[7] G Di Cristina Children Hosp, Palermo, Italy
[8] Univ Bologna, Osped S Orsola Malpighi, Clin Pediat, Bologna, Italy
[9] Osped Riuniti Bergamo, Pediat Unit, I-24100 Bergamo, Italy
[10] Osped Reg Microcitemie, Pediat Unit, Cagliari, Italy
[11] Univ Bari, Dept Biomed Childhood, Bari, Italy
[12] Osped Catania, Unit Pediat Hematol & Oncol, Catania, Italy
[13] Casa Sollievo Sofferenza S Giovanni Rotondo, Pediat Unit, Foggia, Italy
[14] Osped Pausillipon, Hematol Unit, Naples, Italy
[15] Univ Genoa, Clin Infect Dis, Genoa, Italy
[16] Univ Milano Bicocca, S Gerardo Hosp, Clin Pediat, Monza, Italy