Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Rheumatoid Arthritis ?
    ### Response:
    An Inflammatory, Autoimmune Disease Rheumatoid arthritis is an inflammatory disease that causes pain, swelling, stiffness, and loss of function in the joints. It can cause mild to severe symptoms. Rheumatoid arthritis not only affects the joints, but may also attack tissue in the skin, lungs, eyes, and blood vessels.
    