What is rheumatoid arthritis? Rheumatoid arthritis (RA) is a form of arthritis that causes pain, swelling, and stiffness in your joints. RA is an autoimmune disease. Although it is most common in the…

Necrotizing vasculitis is a group of disorders that involve inflammation of the blood vessel walls. The size of the affected blood vessels helps to determine the names of these conditions…

Overview of Rheumatoid Arthritis Rheumatoid arthritis (RA) is a chronic (long-lasting) autoimmune disease that mostly affects joints. RA occurs when the immune system, which normally helps protect the body from infection…