[1] Univ Genoa, Res Lab, Dept Internal Med, IRCCS San Martino AOU, I-16132 Genoa, Italy
[2] Univ Genoa, IRCCS San Martino AOU, Dept Internal Med, Acad Div Clin Rheumatol, I-16132 Genoa, Italy
[3] Univ Belgrade, Sch Med, Inst Rheumatol, Belgrade 11000, Serbia
[4] Univ Ghent, Ghent Univ Hosp, Dept Rheumatol, Fac Med & Hlth Sci,Dept Internal Med, B-9000 Ghent, Belgium