1 Department of Medicine, Unit of Internal Medicine and Rheumatology, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy.
2 Department of Medicine, Unit of Internal Medicine and Rheumatology, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy; Unit of Rheumatology, University of Modena and Reggio Emilia, Azienda Ospedaliero-Universitaria, Policlinico di Modena, Modena, Italy.