Rheumatoid arthritis (
RA) is a long lasting
autoimmune disorder that primarily affects
joints. It typically results in warm, swollen, and
painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are involved, with the same joints typically involved on both sides of the body. The disease may also affect other parts of the body. This may result in a
low red blood cell count,
inflammation around the lungs, and
inflammation around the heart. Fever and low energy may also be present. Often, symptoms come on gradually over weeks to months.