A Rheumatologist is an Internal Medicine, or for children - a Pediatric, medical doctor with additional qualifications enabling specialization in the evaluation and management of inflammatory and other diseases of joints. This specialist diagnoses and treats inflammatory (Lyme disease, rheumatoid arthritis and others) and degenerative arthritis, non-specific myalgia and arthralgia such as chronic fatigue syndrome, and collagen and autoimmune diseases such as lupus.