Add-on
Anti-TPO Antibodies: What a Positive Result Means
All NiaHealth tests are processed in Canadian-certified labs, which are highly trusted by the medical community for their accuracy and reliability. Blood and urine samples are collected by licensed medical professionals and processed using state-of-the-art equipment. NiaHealth is SOC2 Type 2 certified.
Thyroid peroxidase (TPO) is an enzyme responsible for the addition of iodine to thyroglobulin, a critical step in thyroid hormone synthesis. In certain autoimmune conditions, such as autoimmune hypothyroidism (also known as Hashimoto’s thyroiditis), the body makes antibodies against TPO. More than 90% of people with Hashimoto’s thyroiditis have anti-TPO antibodies (Mariotti et al., 1990) , and testing for these antibodies can help to confirm the diagnosis. Approximately 10% of people with normal thyroid function tests (TSH, T4, T3) also have anti-TPO antibodies, which increase the risk of developing hypothyroidism in the future.
Available as an add-on
Anti-TPO is part of our Advanced Thyroid Panel add-on, starting from $100.
Nurse Practitioner reviewed
Canadian-certified labs
SOC2 Type 2 certified
Why it matters
For people with hypothyroidism, a positive anti-TPO antibody titre can be used to confirm the diagnosis of autoimmune (Hashimoto’s) thyroiditis. For people with normal thyroid function tests, a positive anti-TPO antibody titre provides an indication of your risk of developing hypothyroidism in the future. People with anti-TPO antibodies have a 1-2% risk of developing hypothyroidism each year (Vanderpump et al., 1995).
Reference ranges
The reference range NiaHealth has adopted for anti-TPO sets the at-risk threshold at 35 kIU/L, which is the commonly accepted cutoff for a positive anti-TPO titre. However, in a population-based cohort study, a cutoff of 29 kIU/L was found to predict the progression to subclinical hypothyroidism amongst individuals who were euthyroid at baseline (Walsh et al., 2010).
This information is educational and does not replace medical advice, diagnosis, or treatment. Your results should be interpreted with a qualified healthcare professional in the context of your health history.
