1. Rheumatology Section, Internal Medicine and Medical Specialties, P. Giaccone University Hospital, Palermo, Italy.
2. Pathology Section, Internal Medicine and Medical Specialties, P. Giaccone University Hospital, Palermo, Italy.
3. Rheumatology Section, Internal Medicine and Medical Specialties, P. Giaccone University Hospital, Palermo, Italy. giuliana.guggino@unipa.it