1. Allergy and Clinical Immunology Unit, Department of Clinical and Experimental Medicine, University of Messina, Italy
2. Allergy Unit, ASP 5 Messina, Italy
3. Allergy Unit, ASP 6 Palermo, Italy
4. Pneumo-allergy Unit, ASP 9 Trapani, Italy
5. Allergy Unit, “GF Ingrassia” Hospital, ASP 6 Palermo, Italy