1. Department of Rheumatology, Ghent University Hospital, and Department of Rheumatology, AZ Sint-Jan Brugge - Oostende AV, Belgium. yves.piette@ugent.be
2. Department of Laboratory Medicine, Ghent University Hospital, Belgium.
3. Department of Paediatric Rheumatology, Ghent University Hospital, Belgium.
4. Department of Neurology, Ghent University Hospital, Belgium.
5. Department of Rheumatology, Ghent University Hospital, Belgium.
6. Department of Dermatology, Ghent University Hospital, Belgium.
7. Department of Internal Medicine, Ghent University and Praktijk 10A, Maldegem, Maldegem, Belgium.
8. Department of Rheumatology, Ghent University Hospital, and Praktijk 10A, Maldegem, Belgium.
9. Department of Laboratory Medicine, Ghent University Hospital, and Department of Diagnostic Science, Ghent University, Belgium.