Hi. My name's Katyi Brosnan. I'm a registered nurse here in Austin, Texas. And today, I'm going to talk about some of the causes of rheumatoid arthritis. What rheumatoid arthritis, or RA, actually is is an autoimmune disease that is attacking healthy tissue, joints, cartilage, muscles all in certain areas. And so, it's breaking these areas down over time, and it tends to be a chronic, lifelong disease. At this point, it's not known exactly what is causing this. Although, infectious disease doctors have often suspected that it's associated with a viral, bacterial, or fungal infection that happens at some point to trigger this response, but it still hasn't been proven to this point. So the causes are unknown, but there's a lot of treatments out there to help you with rheumatoid arthritis.