1. Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
2. Department of Clinical Pharmacology and Toxicology, University of Milan, Laboratory of Genetics, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
3. Orthopedic and Trauma Unit, Santissima Trinità Hospital, Cagliari, Italy
4. Rheumatology Unit, Department of Internal Medicine, ASST-Fatebenefratelli L. Sacco University Hospital, Milan, Italy