1 Division of Rheumatology, Western University, Schulich School of Medicine &Dentistry, St Joseph's Health Care, 268 Grosvenor Street, London, ON N6A 4V2, Canada.
2 Division of Rheumatology, Allergy, and Immunology, University of California, San Diego, School of Medicine, 9500 Gilman Drive, MC 0943, La Jolla, CA 92093-0942, USA.