1. Department of Autoimmunology and Biomarkers, Statens Serum institute , Copenhagen , Denmark
2. Central Diagnostic Laboratory , Maastricht University Medical Center , Maastricht , The Netherlands
3. Department of Rheumatology and Immunology, Medius Kliniken Kirchheim/Teck , University Tübingen , Tübingen , Germany
4. Department of Internal Medicine, Section Nephrology and Immunology , Maastricht University Medical Center , Maastricht , The Netherlands
5. Department of Rheumatology , Rigshospitalet, Copenhagen , Denmark
6. Clinical Department of Laboratory Medicine , University Hospitals Leuven , 3000 Leuven , Belgium
7. Department of Cardiovascular Sciences , KU Leuven , Leuven , Belgium
8. Clinical Department of General Internal Medicine, Research Department of Microbiology and Immunology , Laboratory of Clinical Infectious and Inflammatory Disorders , University Hospitals Leuven , Leuven , Belgium
9. Maastricht University , Maastricht , The Netherlands
10. Department of Laboratory Medicine , University Hospitals Gasthuisberg , Herestraat 49 , 3000 Leuven , Belgium , Phone: +32 16 347009, Fax: +32 16 34 79 31
11. Department of Microbiology and Immunology , KU Leuven , Leuven , Belgium
12. Department of Laboratory Medicine , University Hospitals Leuven , Leuven , Belgium