Antibodies to thyreperoxidase
Thyroid peroxidase is an enzyme of a glycoproteinic nature. This microsomal antigen is of the greatest importance in the synthesis of thyroid hormones.
In the autoimmune process, autoantibodies are involved in the tissues that form the thyroid gland. The disorder of thyroid function is often associated with it. Great value in this case has antibodies to thyreperoxidase.
The highest concentration is found with thyroiditis Hashimoto. At the last stages of atrophic processes in the thyroid gland their level decreases, in some cases to undetectable values.
Antibodies to thyroid peroxidase are often detected in a Graves' disease. Their prolonged detection during the pathology refers to the risk factors for the subsequent formation of hypothyroidism.
When susceptible to Hashimoto's thyroiditis in women, antibodies to thyperoxidase may be detected during pregnancy. At their increased concentration in the first trimester there is a probability of the development of the disease after childbirth.
Antibodies to thyroid peroxidase may indicate the presence of other thyroid pathologies. Among them, in particular, include adenomas, goitre, thyroid cancer. In addition, antibodies are found in healthy people( approximately 10% of women and 5% of men).
Laboratory testing for their detection should be carried out regardless of the form of the autoimmune process. There is no exception for diabetes mellitus( insulin-dependent), pernicious anemia, adrenal insufficiency( autoimmune character), lupus erythematosus.
The use of individual drugs can trigger the development of hypothyroidism, which is associated with the occurrence of autoantibodies. These include, in particular, lithium preparations, Amiodarone. A similar effect is characteristic for immunostimulating therapy( for example, the use of Interferon).
Determination of antibodies is a sufficiently sensitive test for the detection of autoimmune lesions in the thyroid gland. At the same time, the quantitative index has a more diagnostic significance.
It should be noted that it is impossible to establish the presence of an autoimmune disease in the thyroid gland only on the basis of the detected elevated antibody index.
Absolute indications for the study is a Graves disease, a prognosis of the risk of developing hypothyroidism on the background of an isolated increase in the thyroid-stimulating hormone concentration. In addition, the need for analysis occurs with autoimmune thyroiditis in primary hypothyroidism, as well as the prognosis of postpartum thyroiditis in patients at risk.
Relative indications include
- differential diagnosis of subacute and autoimmune( lymphocytic) thyroiditis on the background of transistor thyrotoxicosis,
- diagnosis of an autoimmune form against the background of euthyroid diffuse or nodular goiter,
- prediction of hypothyroidism in patients at risk, pregnant at early stages.
In the course of treatment of the revealed diseases repeated research is inexpedient. This is due to the fact that his level does not have a prognostic value for a diagnosed disease.
If there is a probability of developing an autoimmune thyroid disease, a second examination is recommended in the first and second years of observation if antibodies to thyreperoxidase are not detected in the primary study. The norm for a healthy person is up to 35 IU / ml.
Today there are no scientifically proven and valid therapeutic methods for AIT( autoimmune thyroiditis).Along with this, against the backdrop of developed hypothyroidism, when antibodies to thyroid peroxidase are increased, treatment of the disease is not a problem for doctors. It is prescribed replacement hormone therapy with the drug "Levothyroxine".