1. Ear, Nose, and Throat Unit, Villa Montallegro Private Clinic, Genoa, Italy
2. Pneumologic and Allergological Paediatric Unit, Istituto G. Gaslini, Genoa, Italy
3. Department of Health Sciences, Genoa University, Genoa, Italy
4. Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Genoa, Italy