1. Pediatric Unit, “San Giuseppe” Hospital, Empoli, Florence, Italy
2. Pediatric Clinic, Department of Pediatrics, University of Parma, Parma, Italy
3. Department of Allergy and Pulmonology, Pediatric Hospital “Giovanni XXIII”, University of Bari, Bari, Italy
4. Pediatric Unit, “Ospedali Riuniti”, University Hospital, Ancona, Italy
5. Children and Mother Care Department, Pediatrics Unit, “Santa Barbara” Hospital, Iglesias, Italy
6. Department of Pediatrics, University of Verona, Verona, Italy