1. Department of Biotechnological and Applied Clinical Sciences; University of L'Aquila; L'Aquila Italy
2. Department of Clinical Chemistry; Ullevaal University Hospital and Institute of Medical Biochemistry; University of Oslo; Oslo Norway
3. Department of Clinical Sciences; Section of Rheumatology; Lund University; Lund Sweden
4. Ospedale Pediatrico Bambino Gesù; Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS); Rome Italy