[1] Univ Puerto Rico, Dept Med, Div Rheumatol, San Juan, PR 00936 USA
[2] Univ Alabama, Sch Med, Dept Med, Div Clin Immunol & Rheumatol, Birmingham, AL USA
[3] Univ Alabama, Sch Med, Dept Surg, Sect Trauma Burns & Crit Care, Birmingham, AL 35294 USA
[4] Johns Hopkins Univ, Sch Med, Div Rheumatol, Baltimore, MD USA
[5] Northwestern Univ, Div Rheumatol, Feinberg Sch Med, Chicago, IL 60611 USA
[6] Univ Texas Hlth Sci Ctr Houston, Dept Med, Div Rheumatol, Houston, TX USA