Rheumatoid arthritis is a systemic autoimmune disease which initially attacks the synovium, a membrane that lines the capsule around joints and secretes a lubricating fluid.
Reviewed By: Joseph V. Campellone, MD, Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.