Thyroid antibodies are often not included in a lab order when screening for a thyroid disorder. We discussed what a complete thyroid lab order should look like but another question that comes up is “Should we check thyroid antibodies?”

Examples of thyroid antibodies include thyroid peroxidase (TPOAb), thyroglobulin antibodies (TgAb), and TSH receptor antibody (TRAb). Thyroid antibodies are proteins that attack different aspects of thyroid function thus affecting thyroid hormone levels.

High levels of thyroid antibodies is a strong indication of an autoimmune thyroid disorder such as Hashimoto’s or Grave’s disease. Hashimoto’s disease will mimic symptoms of hypothyroidism whereas Grave’s disease will present very similarly to hyperthyroidism. Unfortunately, there are very few symptoms that will differentiate between Hashimoto’s disease and hypothyroidism. The same concept applies to Grave’s disease and hyperthyroidism.

For this main reason, I find testing for thyroid antibodies very useful. If thyroid antibodies are elevated, it can change the course of treatment.