1 Scuola di Specializzazione in Pediatria, University of Bari "Aldo Moro", Bari, Italy.
2 Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, China.
3 Pediatric Allergy Unit, Department of Pediatrics, Gynecology and Obstetrics, University Hospitals of Geneva, Geneva, Switzerland.
4 Department of Pediatric Pulmonology and Allergy, Assistance Publique Hôpitaux de Paris, Hôpital Necker Enfants Malades and University of Paris Cité, Paris, France.