Rheumatoid arthritis is an inflammatory condition of the joints which is caused by an autoimmune reaction where the immune system mistakenly recognizes our body tissues as foreign and attacks it.
RA mainly attacks joints, usually many joints at once. RA commonly affects joins in the hand, wrists, and knees. RA can also affect other tissues of lungs, heart and eyes.
RA can be diagnosed based on symptoms, physical examination, and a blood test for autoantibodies.