1 From the Rheumatology Section, Internal Medicine Service Hospital Italiano de Buenos Aires and University Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
2 Department of Rheumatology, University Hospital La Paz, IdiPaz, Madrid, Spain.
3 Hospital Universitario Fundación Santafé de Bogotá, Faculty of Medicine, Universidad El Bosque, Universidad Militar Nueva Granada, and PANLAR Axial Spondyloarthritis and Psoriatic Arthritis Study Group, Bogota, Colombia.
4 Rheumazentrum Ruhrgebiet Herne, Ruhr University Bochum, Bochum, Germany.