Since your TPOab (thyroid peroxidase antibodies) are elevated, my first guess is that you have a thyroid problem. A positive TPOab is indicative of Hashimoto's thyroiditis.
If FREE T3, FREE T4 and TSH haven't already been tested, that's your next step. If they have, please post them with reference ranges. Ranges vary lab to lab, so they have to come from your own lab report.
What are your symptoms?