Question: what are normal tpo antibody levels?
Answer: Antibody Test Results Normal values are as follows: TPO antibody: The measured serum level should be less than 9 IU/mL. Anti-Tg antibody: The measured serum level should be less than 4 IU/mL. Thyroid-stimulating immunoglobulin antibody (TSI): This value should be less than 1.75 IU/L.