Thyroid Peroxidase is a type of enzyme found in the thyroid gland. The main role of Thyroid Peroxidase is to produce thyroid hormones. When the presence of Thyroid Peroxidase (TPO) antibodies are found in the blood, it indicates that you are suffering from an autoimmune disorder.
Autoimmune disorder is of two types:
Hashimoto disease: It is called hypothyroidism which is a form of underactive thyroid. It is not able to make hormones when the thyroid gland is inflamed. As a result, when the thyroid levels get too low, it cannot receive enough of thyroid hormone that is required for the body.
Grave's disease: When the thyroid gland becomes overactive and releases too much hormone into the blood, its called hyperthyroidism.