Anti-TPO Antibodies

Anti-TPO antibodies are immune markers against thyroid peroxidase, an enzyme of the thyroid gland. Elevated levels indicate autoimmune thyroid disease (Hashimoto's).

Normal ranges

Adults: < 34 IU/mL (lab-specific).

Units: IU/mL

Causes of deviations

Low levels:

Negative result is the norm — no autoimmune activity detected.

High levels:

Hashimoto's thyroiditis, Graves' disease, postpartum thyroiditis.

When to see a doctor

If elevated — check TSH and thyroid ultrasound with an endocrinologist.

This information is for educational purposes and does not replace medical advice.

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