Each person who suffers from dysfunctions of the thyroid gland or is examined by an endocrinologist on suspicion of autoimmune diseases, was faced with the need to donate blood for thyroglobulin. What is it, not all doctors explain. Therefore, people begin to search for information on the Internet or from friends. And often this leads to stressful situations, because, according to many, an analysis for thyroglobulin is done with suspected cancer. But this is not always the case. Therefore, those who are faced with the need to conduct such studies need to find out everything about thyroglobulin. You can find out what it is from your doctor or other specialists. This is especially important for women, as they have hormonal disruptions more often.
What is thyroglobulin?
The thyroid gland is represented by an accumulation of small spherical formations - follicles. Inside them, thyroglobulin protein is present in large quantities. What is it, know those who disrupt the production of thyroid hormones. After all, it is this protein that is the basis for their production.
Passing through the cells of the gland, thyroglobulin breaks down into a tyrosine molecule and iodine atoms. Thus, thyroxine is obtained. This protein - a high molecular weight glycoprotein - can provide the production of basic thyroid hormones for two weeks. And it turns out that he is a kind of form for storing them, from which they are released as necessary. Not all patients who are prescribed a hormone test can answer the question: thyroglobulin - what is it? In women, such an examination is done more often, since they are more prone to hormonal malfunctions and dysfunctions of the thyroid gland.
Antibodies to thyroglobulin
What is this, not everyone knows. With some diseases of the thyroid gland, autoimmune aggression of the body is possible. In this case, the synthesis of hormones is disturbed, because antibodies destroy thyroglobulin. What it is? This is a specific reaction of the body’s immune system, which destroys protein using special cells, taking it for an alien element. As a result of this, a person lacks thyroid hormones. Often, symptoms such as weakness, fatigue, weight loss indicate this. And then an analysis is prescribed for antibodies to thyroglobulin.
This is done even in the presence of diseases that increase the risk of thyroid dysfunction:
- Down syndrome;
- insulin-dependent diabetes mellitus;
- rheumatoid arthritis;
- hemolytic anemia.
In addition, such a study should be done to pregnant women with autoimmune diseases in determining the cause of infertility and to identify risk groups among children whose mothers have endocrine disorders.
Blood norm
This protein is mainly found in the follicles of the thyroid gland. Only in very small quantities is thyroglobulin released into the bloodstream. Its norm depends on many factors, and each person has a different one. The amount of thyroglobulin is determined by the size of the thyroid gland, the activity of its functioning and the body's need for hormones.
But there are certain boundaries, the excess of which indicates deviations in the functioning of the thyroid gland. Most often, this occurs when the destruction of its cells is caused by inflammatory processes or external causes. Therefore, an analysis for thyroglobulin is rarely prescribed. The norm of its content in the blood is not more than 50 ng / ml. The analysis can show how large the thyroid gland is, how actively it functions and whether there are inflammatory processes in it. In most cases, when studying the level of thyroglobulin, it is important not the amount in the blood, but the dynamics, that is, an increase or decrease with time.
Indications for analysis
Sometimes it happens that doctors unreasonably prescribe a blood test for thyroglobulin. What this is, not all patients know, and many are scared of such an analysis. But it is not always done with a suspected cancerous tumor. Only in those patients to whom the thyroid gland was removed, such a study is indicated regularly to prevent relapse. In addition, an analysis is made for thyroglobulin and those who are treated with radioactive iodine in order to monitor the effectiveness of therapy.
Assign it in some other cases:
- to study the development of congenital hyperthyroidism in infants;
- to control the development of thyroiditis;
- in a comprehensive study of iodine deficiency;
- to calculate the effectiveness of therapy for hyperthyroidism.
How to pass the analysis?
“Blood is taken from a vein in the morning, on an empty stomach.” It is advisable not to eat already in the evening, not to smoke, to exclude large physical exertion and to avoid stressful situations.
- To obtain reliable results, it is also necessary to do an analysis for anti-thyroglobulin. What it is? These are antibodies to a protein that destroy it. If there are a lot of them, then the level of thyroglobulin in the blood will be low.
- Three weeks before the blood donation, you need to stop treatment with drugs containing thyroxine and other thyroid hormones.
- An analysis to determine the recurrence of cancer is done no earlier than three months after surgery or six months after the use of radioactive iodine.
Thyroglobulin is elevated - what does it mean?
If a lot of this protein is released into the blood, this may be a consequence of the destruction of the thyroid cells. This can happen with various endocrine and autoimmune diseases. Therefore, increased thyroglobulin indicates that the patient may have:
- thyroiditis;
- diffuse toxic goiter;
- Bazedova's disease ;
- benign adenoma;
- purulent inflammation of the thyroid gland;
- complications after surgery, biopsy of the thyroid gland or its injury;
- destruction of thyroid cells for other reasons.
Also, an increase in the level of this protein in the blood happens after using radioactive iodine for the diagnosis and treatment of tumors. The thyroglobulin level is also slightly increased in patients with Down syndrome, in patients with severe hepatic insufficiency, or during pregnancy.
What can affect the results of the analysis?
Most often, false results are detected in the presence of antibodies to thyroglobulin. Therefore, their presence also needs to be identified. The results may be affected by hormonal medications, iodine preparations, the presence of chronic infectious diseases, or a genetic predisposition. In addition, the analysis may be unreliable due to radiation exposure or the presence of toxins in the blood. Even severe stress can affect the level of thyroglobulin and antibodies to it. It was found that the concentration of this protein increases during pregnancy, as well as in women in old age. And taking oral contraceptives leads to an increase in antibodies to thyroglobulin. It may also affect the results of the analysis.
Is thyroglobulin an oncomarker?
Many patients who have not been explained what the analysis is done for, turn to online sources. They are interested in the question: thyroglobulin is elevated - what does this mean? Often they find the wrong answer, which leads to severe stress. Indeed, some sources believe that thyroglobulin is a tumor marker and its elevated level indicates a risk of cancer.
But actually it is not. Most often, such an analysis is done after removal of the thyroid gland to control the formation of metastases. After all, thyroglobulin can be produced not only by the gland itself, but also by a cancerous tumor. Therefore, this protein is an oncomarker only in the absence of a thyroid gland. After successful cancer therapy, such patients are tested for thyroglobulin several times a year. Only in this way can relapse be determined. But the primary tumor can not be determined in this way, since the level of this protein in the presence of a functioning thyroid gland is not associated with the development of the tumor.