TPO and thyroiditis: The normal ranges of the thyroid function tests provided from our institution were as follows: T4, 5.26–9.77 μg/dL; T3, 0.61–1.70 ng/mL; free T4, 0.80–1.23 ng/dL; TSH, 0.41–4.30 μIU/mL; thyroglobulin Ab, 0–130.6 IU/mL; anti-TPO Ab, 0–13.7 IU/mL; and PTH, 15–65 pg/mL.