1. Allergy Unit, Department of Pediatrics, Anna Meyer Children’s University Hospital, Florence, Italy
2. Service de Pneumologie et Allergologie Pédiatriques, Hôpital Necker-Enfants Malades, Paris, France
3. Faculty of Medicine, Université Paris Descartes, Paris, France
4. Division of Pediatric Allergy, Department of Pediatrics, University Hospitals of Geneva, Geneva, Switzerland