What are antibodies to TPO?
Antibodies to TPO are autoantibodies to a specific enzyme of the thyroid gland - thyroperoxidase. Relatively recently was discovered. This pathology occurs, as a rule, in women. But in recent years, the disease has been increasingly diagnosed in children. In this regard, widespread blood test for antibodies to TPO. In patients with autoimmune thyroiditis, an increase in titer is noted.
Antibodies to TPO: functions
Thyroid peroxidase contributes to the formation of the active form of iodine, which, in turn, has properties to be included in the iodification of thyroglobulin. Atitela to TPO is an indicator of the aggression of immunity in relation to its own organism. They block the enzyme activity, resulting in reduced production of T3 and T4 (thyroid hormones). At the same time, AT of thyroid peroxidase can be only “witnesses” of autoimmune processes. The test for antibodies to TPO is considered the most accurate indicator of the presence of thyroid disease. As a rule, their appearance indicates the first shift, which is observed on the background of progressive hypothyroidism during the course of Hashimoto's thyroiditis. It is characteristic that AT thyroperoxidases are found in 85% of people with Graves' disease and in 95% with Hashimoto thyroiditis. Detection of antibodies in the prenatal period indicates a high risk of postpartum thyroiditis in the mother. Probably a negative impact on the development of the child.
In what cases is the analysis done?
Antibodies to TPO can be detected in newborns, patients with hypothyroidism, as well as in the presence of Graves' disease in the mother after childbirth. An adult study recommended for the differential diagnosis of hyper- and hypothyroidism, with goiter, and dense swelling of the legs. Ophthalmopathy, an increase in the eye tissue (suspicion of the development of euthyroid Graves disease), is also referred to indications. Antibodies to TPO, the rate of which in patients up to 50 l - 0-35, older than 50 l - 0-100 U / ml, can be increased in healthy people. In such cases, only the carrier of thyroid peroxidase occurs. At the same time, people do not have a predisposition to the development of autoimmune thyroiditis. When making a diagnosis, several factors should be considered. In particular, the patient, in addition to the increased titer, must have specific changes in the thyroid gland, detected by ultrasound.Another mandatory criterion is a clear or subclinical hypothyroidism.
Increased titer of AT thyroperoxidase
High rates may indicate the development of a number of pathologies. In particular, they include goiter, postpartum thyroid dysfunction, subacute thyroiditis. An increased amount of antibodies may indicate idiopathic hypothyroidism, non-thyroid autoimmune pathologies. However, in the absence of one of the three criteria above, the diagnosis may be erroneous. Before the patient receives a referral for laboratory research, the specialist determines the indications for the purpose of the analysis. With a positive result, replacement therapy is indicated.