1. Internal Medicine Department, Hospital Universitario de Ourense, Ourense, España
2. Internal Medicine Department, University Tunis El Manar, Faculty of Medicine of Tunis, Tunis, Tunisia
3. Internal Medicine Department, Hospital Garcia de Orta, Almada, Portugal
4. Internal Medicine Department – Medicina II, Centro Hospitalar Universitário de Lisboa-Norte, Hospital de Santa Maria, Lisboa, Portugal and
5. Rheumatology department, Centre for Rheumatology Research, University College London, London, UK