[1] Univ Hosp Bern, Dept Rheumatol & Clin Immunol & Allergol, CH-3010 Bern, Switzerland
[2] Cornell Univ, Hosp Special Surg, Joan & Sanford Weill Coll Med, Barbara Volcker Ctr Women & Rheumat Dis, New York, NY 10021 USA
[3] Univ Padua, Dept Clin & Expt Med, Div Rheumatol, Padua, Italy
[4] Univ Roma La Sapienza, Cattedra Reumatol, Rome, Italy
[5] Univ Milan, Ist Auxol Italiano, Dept Internal Med, Allergy Clin Immunol & Rheumatol Unit,IRCCS, Milan, Italy
[6] Univ Birmingham, Div Immun & Infect, Rheumatol Res Grp, Birmingham B15 2TT, W Midlands, England
[7] Osped Riuniti Bergamo, Dept Internal Med, I-24100 Bergamo, Italy
[8] Univ Brescia, Brescia, Italy