A rheumatologist treats disorders of the muscles, bones, joints and internal organs due to rheumatic diseases and arthritis, according to the American College of Rheumatology. Rheumatoid arthritis, systemic lupus erythematosus and Raynaudﾒs phenomenon are some conditions rheumatologists treat, explains Hedley Orthopaedic Institute.
Rheumatoid arthritis is an inflammatory condition affecting the joints, primarily the small joints in the feet or hands, notes Mayo Clinic. The body's immune system attacks the joints causing swelling and pain, which if left untreated, results in permanent joint deformities. Rheumatoid arthritis can also affect other organs, such as the eyes, skin, lungs and blood vessels.
Systemic lupus erythematosus, also known as SLE or lupus, is another autoimmune disease that rheumatologists treat, notes the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Lupus symptoms vary among patients depending on the type of lupus, but the disease attacks internal organs, such as the heart, lungs and kidneys as well as the skin and joints.
Raynaud's phenomenon causes cold hands and feet in patients with the diagnosis due to blood flow problems, states WebMD. Doctors do not know what causes it, but the disease is often a symptom of another autoimmune disease, such as lupus, rheumatoid arthritis or scleroderma. Cold weather, smoking, certain medications, caffeine and sometimes stress often trigger symptoms of the disease.