1. Hematology and Bone Marrow Transplantation Unit, University of Perugia, Perugia, Italy;
2. Department of Women’s and Children’s Health, University of Padova, Padova, Italy; and
3. Centro Ricerca Tettamanti, Clinica Pediatrica, Università di Milano-Bicocca, Ospedale S. Gerardo, Monza, Italy