Rheumatoid arthritis (RA) is an autoimmune disease which can cause joint pain and damage throughout your body.The joint damage that RA causes usually happens on all sides of the body. So, if a joint is affected in your arms or legs, an equivalent joint within the other arm or leg will probably be affected, too. This is a method that doctors distinguish RA from other sorts of arthritis, like osteoarthritis (OA).
Symptoms
It is also a systemic disease, which suggests it affects the entire body.It occurs when a person’s system mistakes the body’s healthy tissues for foreign invaders. As the immune system responds, inflammation occurs in the target tissue or organ.