Rheumatic diseases are painful autoimmune and inflammatory diseases that cause the immune system to attack a person’s joints, muscles, bones, and/or organs. Rheumatoid arthritis, osteoarthritis, lupus, Sjogren’s syndrome, gout, scleroderma, and psoriatic arthritis are some of the most commonly known. Chances are, if you don’t have a rheumatic disease, you know somebody who does. More than 54 million American adults – one in four – have been diagnosed with one.