1 Research Laboratory and Academic Division of Clinical Rheumatology, Department of Internal Medicine, University of Genova, Polyclinic San Martino Hospital, Genoa, Italy.
2 Clinical Immunology, Department of Internal Medicine, University of Genova, Polyclinic San Martino Hospital, Genova, Italy.
3 Department of Rheumatology, Ghent University Hospital, Department of Internal Medicine, Ghent University, Ghent, Belgium.