1. Pediatric Unit, “Maggiore” Hospital, Crema, Department of Pediatrics, University of Pavia, Italy
2. Department of Pediatrics, “San Matteo” Foundation IRCCS, University of Pavia, Pavia, Italy
3. Pediatric Unit, “San Giuseppe” Hospital, Empoli, Florence, Italy
4. Pediatric Clinic, Department of Pediatrics, University of Parma, Parma, Italy
5. Allergy Unit, Department of Pediatrics, University of Messina, Messina, Italy
6. Allergy Unit, Pediatric Unit, “G.B. Grassi” Hospital, Rome, Italy