1. Paediatrics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
2. Specialty School of Pediatrics, Alma Mater Studiorum, University of Bologna, 40138 Bologna, Italy
3. Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
4. Clinica Pediatrica, Azienda Ospedaliero-Universitaria, Medicine and Surgery Department, Università di Parma, 43126 Parma, Italy