1. Rheumatology Unit; Department of Medicine; University of Perugia; Perugia Italy
2. Rheumatology Unit; Department of Clinical and Experimental Medicine; University of Pisa; Pisa Italy
3. Unit of Internal Medicine; Department of Medicine; Terni University Hospital; Terni Italy
4. Department of Medical and Biological Sciences; Rheumatology Clinic; University of Udine; Udine Italy
5. Rheumatology Unit; Sapienza University of Rome; Rome Italy
6. Rheumatology Unit; Department of Biotechnological and Applied Clinical Sciences; University of L'Aquila; L'Aquila Italy
7. Internal Medicine, Endocrine and Metabolic Sciences Section; Department of Medicine; University of Perugia; Perugia Italy