A rheumatologist is a medical doctor who specializes in the diagnosis and treatment of musculoskeletal diseases and certain autoimmune conditions. They are internists or pediatricians who have received additional training in rheumatology, which is the medical specialty that deals with musculoskeletal conditions, as well as autoimmune and inflammatory conditions in people of all ages. Rheumatologists must complete three to four years of medical or osteopathic education followed by three years of residency training in either internal medicine or pediatrics. After residency, they must enroll in a rheumatology fellowship for two to three years to specialize in diagnosing and treating musculoskeletal and autoimmune conditions. Some rheumatologists are trained in both internal medicine and pediatrics. Rheumatic diseases are sometimes complex and difficult to diagnose, so rheumatologists will gather a complete medical history and perform a physical exam to look for signs and symptoms that may give clues to the cause of the problem. They consider every organ system when looking for the cause of symptoms. Examples of diseases that may be treated by a rheumatologist include rheumatoid arthritis, osteoarthritis, systemic lupus erythematosus, vasculitis, Sjogren’s syndrome, gout, scleroderma, antiphospholipid syndrome, myositis, sarcoidosis, polymyalgia rheumatica, and temporal arteritis. Seeing a rheumatologist early on can help patients avoid waiting before receiving a diagnosis.