The thyroid gland is the most important organ that regulates many processes. If there is a suspicion of a disruption in its functioning, an AT test for TPO hormone can be prescribed. This abbreviation stands for "thyroid peroxidase autoantibodies."
In some cases, the protective system malfunctions, as a result of which it begins to consider the hormone produced by its own organism as foreign. It is important to know that AT to TPO is such a peculiar indicator of the state of the thyroid gland. Deviation of its indicator from the norm most often indicates the development of autoimmune pathologies.
AT to TPO: concept
Thyroperoxidase is a protein compound that is directly involved in the synthesis of thyroid hormones. Normally, the body’s immune system does not respond to the presence of TPO in the blood.
Under the influence of various adverse factors, protective forces begin to function incorrectly. The immune system triggers the process of active production of antibodies. Thus, it is necessary to understand that anti-TPO antibodies are substances that take thyroperoxidase as a foreign compound and begin to attack it.
This happens under the influence of provoking factors, which include:
- Radiation therapy of cancer.
- Various types of thyroid injury.
- Unsuccessful organ surgery.
- Lack or, conversely, an excess of iodine in the body.
- Active activity of viral, infectious or bacterial agents.
If thyroid damage is suspected, blood tests for the hormone TSH and AT for TPO are prescribed. The more antibodies there are in the biomaterial, the mass destruction of the cells secreting the most important hormones T3 and T4.
Indications
A blood test for antibodies to TPO is prescribed if the patient has the following warning signs:
- A sharp decrease or increase in body weight.
- Constant feeling of tiredness.
- Frequent episodes of increased or decreased body temperature.
- Excessive sweating.
- Unexplained anxiety.
- Insomnia.
In addition, the following conditions are indications for the purpose of AT analysis for TPO:
- Thyroid dysfunction.
- Neonatal hypothyroidism.
- Diagnosis of infertility (female).
- Evaluation of the thyroid gland before the appointment of hormonal medications.
- Thyroiditis.
- Violation of the structure of the thyroid gland detected during ultrasound.
The study is also prescribed for pregnant women whose TSH concentration is more than 2.5 units.
Norm indicators
Reference values may vary between laboratories. In this regard, it is recommended to take biomaterial for analysis in the same medical institution (this is relevant for patients who need to evaluate the dynamics of changes).
Standard values are from 0 to 34 IU / ml. Extended norm indicators for different categories of persons (also expressed in IU / ml):
- Women less than 50 years old. The minimum is 0, the maximum is 34.
- Women over 50 years old. The norm is from 0 to 100.
- Men less than 50 years old. Norm indicators are in the range of 0-34.
- Men over 50 years old. The value must not exceed 85.
For pregnant women in the first trimester, the indicator should not be more than 25. In the last gestational periods, the norm is from 30 to 56.
Analysis preparation
It is important to know that AT to TPO is such a very sensitive indicator. Failure to comply with training rules often leads to false results.
Doctor's recommendations:
- Biomaterial must be taken on an empty stomach. The last meal should take place no later than 8 hours before the study. Tea, coffee and juices are also banned. Allowed only to drink clean still water.
- Psychoemotional and physical condition significantly affect the result of the study. A person at the time of blood donation should not be tired, excited or out of breath. In such situations, it is recommended to sit at the doctor’s office for 15 minutes and calm down.
- For 48 hours, you must abandon the use of alcohol-containing drinks.
- It is forbidden to smoke right before the delivery of the biomaterial.
- It is important to inform the doctor about taking any hormonal drugs (including combined oral contraceptives). If necessary, he will for some time cancel the treatment with their help.
Not only non-observance of the above conditions can lead to a false result. When decoding, the doctor should take into account factors such as a genetic predisposition and diseases of a chronic nature.
Reasons for the increase
It is important to understand that AT to TPO is such an indicator, a significant increase of which, as a rule, indicates serious pathologies.
The main causes of deviation from the norm:
- Diffuse or nodular toxic goiter.
- Thyroiditis, both acute and chronic.
- Idiopathic hypothyroidism.
In some cases, antibodies to TPO increase due to diseases that are not associated with thyroid dysfunction. These include the following pathologies:
- Diabetes mellitus insulin-dependent form.
- Rheumatoid arthritis.
- Systemic lupus erythematosus.
- Vasculitis.
In women during pregnancy, an elevated level of antibodies may indicate the development of hyperthyroidism in the fetus.
Finally
The thyroid gland is an organ that performs a number of critical functions. If there is a suspicion of a violation of its functioning, an analysis for antibodies to thyroperoxidase can be prescribed. The production of antibodies is the body's response to the penetration of foreign agents into it. But in this case, a failure occurs in the immune system, and it begins to actively synthesize antibodies whose task is to destroy TPO.