Rheumatoid arthritis is a disorder in which the body's own immune system starts to attack body tissues. The attack is not only directed at the joint but to many other parts of the body. In rheumatoid arthritis, most damage occurs to the joint lining and cartilage which eventually results in erosion of two opposing bones. Rheumatoid arthritis often affects joints in the fingers, wrists, knees and elbows. The disease is symmetrical (appears on both sides of the body) and can lead to severe deformity in a few years if not treated. Rheumatoid arthritis occurs mostly in people aged 20 and above.

In children, the disorder can present with a skin rash, fever, pain, disability, and limitations in daily activities. Often, it is not clear why the rheumatoid arthritis occurred. With earlier diagnosis and aggressive treatment, many individuals can lead a decent quality of life. The drugs to treat rheumatoid arthritis range from corticosteroids to monoclonal antibodies given intravenously. Surgery may be required to replace joints but there is no cure for the illness.