1. Department of Internal Medicine, Hôpital Universitaire de Bruxelles (H.U.B.), Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
2. Department of Medicine, Division of Rheumatology, Inflammation, and Immunity, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
3. Department of Medicine, Division of Immunology and Allergy, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland
4. Immunology and Allergology, Institut Central des Hôpitaux, Valais Hospital, 1951 Sion, Switzerland
5. Rheumatology Private Practice, 11635 Athens, Greece
6. Department of Medicine, Division of Internal Medicine, Lausanne University Hospital, University of Lausanne, 1005 Lausanne, Switzerland