I looked up peroxidase antibodies online. These antibodies specifically attack the enzyme that produces thyroid hormones and it can be caused by an autoimmune disease. From what I can understand about AS is that the immune system is overactive and producing a lot of antibodies, which then attack the joints and cause inflammation, pain and joint damage. I don't totally understand it yet, but I almost NEVER get sick. I think if you are on the biologicals or DMARDS, they weaken the immune system to slow down the attacks. I just started taking a DMARD (methotrexate) and I have felt like I was starting to catch a cold, but it went away.
