When Anti-TPO Antibodies Are Present

Elevated anti-thyroid peroxidase (anti-TPO) antibodies are a hallmark of autoimmune thyroid disease, found in over 90% of individuals with Hashimoto’s thyroiditis and approximately 50–70% of those with Graves’ disease. While anti-TPO is a key marker in Hashimoto’s, the primary antibody in Graves’ disease is the TSH receptor antibody. Elevated antibodies do not necessarily mean that a thyroid disorder like hypo or hyper-thyroidism is present. 

The presence of these antibodies indicates that your immune system could be attacking the enzyme essential for thyroid hormone production, leading to chronic inflammation and gradual destruction of thyroid tissue. If you test positive for these antibodies, it is likely you always will, as it represents a general pre-disposition, not a thyroid disease in of itself.

You may experience no symptoms at all, as thyroid autoimmunity can be present for years before causing noticeable dysfunction, if at all. However, if the autoimmune process progresses, symptoms of hypothyroidism typically develop: persistent fatigue that doesn't improve with rest, unexplained weight gain despite normal eating habits, increased sensitivity to cold, dry skin and brittle hair, constipation, depression or mood changes, brain fog and memory problems, muscle weakness and joint pain, and irregular menstrual periods in women.

The presence of Anti-TPO antibodies significantly increases your risk of developing other autoimmune conditions, including type 1 diabetes, coeliac disease, rheumatoid arthritis, and vitiligo. This clustering occurs because the underlying immune system dysfunction that creates Anti-TPO antibodies can also target other organs and tissues.