Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease that causes persistent sym-metrical joint synovitis (inflammation of the synovial membrane) typically of the small joints of the hands and feet, although any synovial joint can be affected. Synovitis presents as pain and pro-longed stiffness that tends to be worse at rest or following periods of inactivity, swelling, tender-ness, and heat in the affected joints. Other symptoms of rheumatoid arthritis include rheumatoid nodules and non-specific symptoms such as malaise, fatigue, fever, and weight loss. As the disease progresses, it can cause joint deformity and affect different organs of the body, such as the heart, lungs, and eyes; therefore early diagnosis and treatment of rheumatoid arthritis is essential to re-duce the impact of the disease. Palindromic rheumatism is a rare form of inflammatory arthritis which causes attacks of joint pain and swelling similar to rheumatoid arthritis, but the joints return to normal in between attacks. Patients with palindromic rheumatism may later develop rheuma-toid arthritis. Rheumatoid arthritis affects around 400,000 adults aged 16 and over in the UK. It can affect anyone of any age. It can get worse quickly, so early diagnosis and intensive treatment are important. This chronic disease affects over 1.3 million Americans and as much as 1% of the world-wide population. The specific cause of RA is not known, and as a result there is no known cure for the disease. Researchers do know, however, that RA is the result of an autoimmune disorder. It is one of the most common autoimmune disorders - more common than psoriasis, Crohn's disease, multiple sclerosis, and lupus.