1. Department of Nephrology and Rheumatology, University Medical Center Göttingen, Göttingen, Germany
2. Department of Rheumatology, King’s College Hospital, London, UK
3. Department of Rheumatology, Division of Medicine, Rayne Building, University College London, London, UK
4. Department of Rheumatology and Clinical Immunology, St Josef-Stift Sendenhorst, Sendenhorst, Germany