Functions, hormones and pathologies of the thyroid gland. What hormones are produced by the thyroid gland This hormone is produced by the thyroid gland

What thyroid hormones are tested?

At the moment, the Internet is replete with materials on medical topics. In particular, there are articles on the topic of a blood test to assess the level of hormone production. thyroid gland. As a rule, these texts are not written by doctors, and therefore are illiterate and contain a lot of factual errors. Such materials will not answer questions, but will only confuse the reader even more.

Among the thyroid hormones, ignorant authors include, in addition to and also, TSH and TPO. But this is fundamentally wrong.

The first two hormones are classified as thyroid hormones quite rightly. They are actually synthesized by the thyroid gland. While TSH is a non-specific hormone, the synthesis of which is carried out by another endocrine organ - the pituitary gland.

The pituitary gland is a small gland located in the brain. The main function of the pituitary gland is to regulate the work of the entire endocrine system.

Thus, TSH (the so-called thyroid-stimulating hormone) is the “signal” hormone of the pituitary gland. Thanks to its effect, the thyroid gland increases the intensity of work and releases more active substances.

TPO also cannot be classified as a thyroid hormone. This substance is not a hormone at all, but is an antibody. The immune system secretes it to destroy iodine-containing substances. However, all four of the above substances must be considered together, since they are closely related to each other and form the mechanism of the thyroid gland.

Thyroxine (tetraiodothyronin or T4). One of the two main thyroid hormones. It makes up the majority of all compounds synthesized by the thyroid gland (up to 90%).

Triiodothyronine (T3). It is another thyroid hormone. Its activity exceeds the activity of T4 by 1000%. The composition of T3 includes three iodine atoms, not 4, so the chemical activity of the hormone increases significantly. Many consider triiodothyronine to be the main thyroid hormone, and T4 as the “raw material” for its production. T3 is synthesized from T4 by acting on the 4-atom hormone with selenium-containing enzymes.

Both T3 and T4 are specific thyroid hormones, that is, they belong to the thyroid hormones. Their synthesis is necessary for the normal functioning of the autonomic and nervous systems, as well as for the basic metabolism, due to which the functioning of autonomous energy-consuming processes occurs: contraction of the heart muscle, transmission of nerve signals, etc.

Specific hormones can exist both in a free and in a bound state. For this reason, several graphs are often distinguished in the results of laboratory tests: free T3-hormone or free T4-hormone. May also be referred to as FT3 (Free T3) or FT4 (Free T4). Most of the thyroid substances are in a state associated with protein compounds. When hormones are released into the blood, they combine with a special TSH protein (thyroid-binding globulin) and are transported to the necessary organs and systems. As soon as the transport is completed, the thyroid hormones return to the free form.

Free hormone has activity, therefore, to assess the functioning of the thyroid gland, the study of this indicator is necessary and most informative.

TSH is a pituitary hormone that affects the functioning of the thyroid gland by acting on the receptors of thyrocyte cells.

Such an impact can cause the following consequences:

Increasing the intensity of the synthesis of thyroid hormones (due to the fact that thyroid cells begin to work more actively);

Thyroid tissue growth. As tissues grow, diffuse changes in the organ increase.

The next most important indicator is antibodies. An assessment of the amount of antibodies to iodine-containing compounds is necessary for a correct diagnosis.

There are three types of antibodies:

Proteins to TPO (thyreoperoxidase);

Proteins to TG (thyroglobulin);

Proteins to rTTH (TSH receptor).

In the results laboratory research most often, abbreviated forms of the names of substances are indicated. AT is an antibody. TG, rTTG, TPO.

Antibodies to thyroperoxidase

TPO is one of the main enzymes directly involved in the synthesis of thyroid hormones. Depending on the degree of deviation of the result from the normal, an increased concentration of these antibodies may not manifest itself in any way, or lead to (a decrease in the level of thyroid hormone production). Elevations are relatively common, affecting about 10% of women and half as many men (5%) globally.

Since the concentration of iodine-containing substances in the thyroid gland is maximum, thyroperoxidase disrupts the work of thyrocyte cells. As a result, the amount of thyroid hormone produced decreases. It is impossible to unequivocally call the excess of the indicator a marker of the disease, however, studies and statistics show that an increase in the content of TPO leads to hypothyroid diseases of the thyroid gland about 5 times more often than in similar cases when the level of hormones is normal.

A blood test for the presence of this substance is carried out in order to identify diffuse toxic goiter of the thyroid gland and.

Antibodies to thyroglobulin

Exceeding the level of antibodies to thyroglobulin is much less common than a similar result for antibodies to thyroperoxidase. According to statistics, the number of persons with a positive deviation from the norm is approximately 5% of women and about 3% of men.

The indicator is quite variable and can indicate the presence of two types of diseases:

In the second case, they speak of two forms of cancer: follicular or papillary, since it is with these types of tumors that an increased production of triglycerides occurs. Thyroglobulin is produced only by thyroid cells or malignant tumor cells. If an excess of the norm is detected, both the patient and the attending physician should be wary. TG simultaneously acts as a tumor marker.

After the operation to remove, along with the affected thyroid gland, the level of thyroglobulin should fall to the minimum marks (down to zero). If this does not happen, the reason lies in the recurrence of cancer.

It must be taken into account that when increased rate anti-TG antibodies, the result may be incorrect. Antibodies create a single structure with the iodine-containing protein TG and are so tightly bound that it is impossible to distinguish between the protein secreted by lymphocytes and thyroglobulin itself in a laboratory study. To assess the level of TG, it is necessary to conduct an independent analysis.

You also need to keep in mind that an excess of thyroglobulin levels is far from always an indicator of oncology. It is simply pointless to analyze the concentration of TG in the blood in patients with an unremoved thyroid gland. An excess of TG can be considered a tumor marker only if the gland has been removed.

In patients with other changes in the organ, the TG indicator may differ from the norm for many reasons: diffuse pathological transformations of the endocrine organ, in which the volume of the organ tissue grows, nodular formations, etc. If a relatively healthy patient is prescribed a blood test for thyroglobulin, this means only one thing: the clinic conducting the analysis wants to cash in on the person’s ignorance and includes in the list of laboratory tests what is not needed.

To identify the presence of cancer in patients whose thyroid gland has not been removed, it is advisable to prescribe a blood test for calcitonin content. This is a really important marker of oncology. It allows you to identify the medullary form of thyroid cancer. C-cell cancer is an extremely dangerous and practically incurable on final stages disease. Neither chemotherapy nor radiation therapy do not give any adequate results. The only way to cure this thyroid tumor is to have surgery on time. For this, it is necessary to detect the disease in time.

As a rule, in patients with diffuse changes in the organ, the likelihood of developing medullary cancer is minimal. If nodular and are present, a blood test for calcitonin is mandatory. The study of venous blood should be carried out in conjunction with a fine needle biopsy.

Antibodies to rTTG

An analysis for the presence of antibodies to thyroid-stimulating hormone receptors is prescribed for patients with confirmed thyroid diseases (for example, with diffuse toxic thyroid goiter).

The study of venous blood is carried out against the background conservative therapy drugs that reduce the level of production of specific active substances. As studies show, the outcome of the disease often depends on the level of decrease in antibodies to rTSH. If therapy does not bring the desired effect, and the degree of antibody concentration does not decrease, this means an unfavorable course of the disease. In this case, the patient should be prescribed surgical treatment.

However, exceeding the limit in itself is not absolute reading To surgical intervention. When making a decision, the doctor must proceed from a system of factors: the general course of the disease, the degree of nodular and diffuse changes, goiter size, etc.

Thus, a person with suspected thyroid pathology or with a confirmed organ disease needs to conduct a venous blood test for the following indicators:

T3 (triiodothyronine);

T4 (tetraiodothyronine or thyroxine);

Antibodies to thyroglobulin;

Antibodies to thyroperoxidase.

To investigate or not other indicators - the endocrinologist decides, based on the patient's history.

Why does the thyroid gland produce hormones?

The thyroid gland produces hormones to create the basis necessary for the normal functioning of all systems and organs. Thanks to it, a stable energy metabolism in the body and the work of the autonomic nervous system are ensured.

Figuratively, the body can be imagined as a multi-storey building powered by coal, and the functioning of the thyroid gland can be imagined as the work of a coal-fired boiler plant. Coal in this case is the thyroid hormones themselves.

If you add too much coal to the boiler room, it becomes hot in all rooms. The people who work in the building suffer from too high temperature, sweat, lose consciousness, etc. If too little coal is added, the heating effect will not be enough, the rooms will freeze. People will begin to suffer already about the cold, dress warmer and try to hide from the low temperature.

Obviously, in both cases, there is no normal mode of operation, and everyone will only think about how to hide from adverse conditions.

In the given example, human workers represent all other hormones (pituitary, adrenal, pancreas, etc.) produced by the human body, as well as organs and systems.

In the normal state, the role of the thyroid gland is almost imperceptible, but as soon as failures and violations begin, serious consequences arise. The thyroid gland provides the necessary base for the minimally efficient and stable functioning of the whole organism.

Depending on the type and form of pathological changes in the thyroid gland, two main cases are possible:

Too many hormones are synthesized (excess);

Specific hormones are not enough for the normal functioning of the body (deficiency).

Excess thyroid hormones (thyroid hormones)

By analyzing venous blood, it is quite easy to determine the excess amount of thyroid hormones. This position is called "hyperthyroidism", and its consequences for the body are called.

With an excess of thyroid hormones, a number of symptoms are observed:

Hyperthermia. In other words, . Persistent and periodic, up to subfebrile condition (marks at 37.1 - 37.7);

Strengthening mental and motor activity. The person becomes aggressive, nervous and overly excitable;

Change in body weight. The weight of the body steadily falls, despite the fact that the patient has a brutal appetite and consumes more food;

Tremor. There is a trembling of the limbs (fingers and the hands themselves are shaking), and sometimes the head.

At later stages or with a significant deviation of the level of thyroid hormones from the norm, more formidable manifestations of hyperthyroidism are observed:

Cardiac disorders. Vascular hypertonicity, increased pressure and persistent even in the absence of physical activity;

Disorders of the nervous system. A person suffers from intelligence, concentration and memory;

Disorders of the functioning of the digestive tract. There are frequent constipation or diarrhea, "indigestion", upset stomach and intestines.

With hyperthyroidism, systemic disorders in the work of all organs are noted.

An indicator of hyperthyroidism is elevated level triiodothyronine and tetraiodothyroxine (T3 and T4). At the same time, the level of the pituitary hormone TSH decreases sharply. If an increased concentration of free thyroid hormones is detected in the blood, even to a small extent, the patient is prescribed special treatment in order to normalize their content.

If the excess is significant, and conservative treatment does not give the necessary results, surgical intervention is prescribed.

Lack of thyroid hormones

A condition in which the level of specific substances of the thyroid gland in the blood is below the indicated minimum is called hypothyroidism.

Hypothyroidism is characterized by the following manifestations:

Hypothermia. Decrease in body temperature to 35.5 ° C. The temperature does not return to normal even with physical activity;

Pressure drop. below normal levels (up to 90-85 / 60-50). There is hypotension;

Edema. Fluid is excreted from the body at a very slow rate. The normal functioning of the excretory system is disturbed, the kidneys cope worse. Serious swelling of the limbs and face occurs;

Insomnia. At night, the patient cannot sleep, and during the day he feels weak, lethargic, and weak. The biological rhythm goes astray;

Increase in body weight. Often accompanied by . The reason for this is a decrease in the metabolic rate;

Insufficient efficiency of other endocrine glands. Contributes to the occurrence of adverse effects. A decrease in the level of production and exposure of sex hormones entails the extinction of libido and sexual dysfunction, failures of the monthly cycle. The weakening of the secretion of digestive hormones contributes to unstable, malfunctioning digestive system. A decrease in the production of pituitary substances affects the functioning of the nervous system and the body as a whole;

Deterioration of the skin and nails. The skin becomes dry and flabby, the nails become brittle, the hair falls out.

With a decrease in the level of hormones to critical levels, there is also a deterioration in the work of the heart (etc.). A venous blood test reveals a reduced level of thyroid substances. Simultaneously with the analysis for hormones, an analysis for antibodies to thyroperoxidase (TPO) should also be carried out to identify the cause of dysfunction. The source may be an autoimmune disease.

At the same time, both too much and not enough thyroid hormones nullify the reproductive function of the human body. Thyroid problems are one of the main causes of pregnancy difficulties. Women, both already pregnant and planning motherhood, also need to pay attention to the TSH indicator.

A serious problem is hormonal dysfunction in children and adolescents. If at an early and transitional age there is an excess or deficiency of thyroid hormones, there is a risk of mental retardation due to underdevelopment of the brain or problems with the nervous system.

Thus, the active substances of the thyroid gland, for all their invisibility, play a major role in the functioning of the body and the normal life of a person. Deviation in the level of thyrotropic active substances leads to severe systemic disorders that significantly reduce the quality of life.

What tests for thyroid hormones are taken in various cases?

if the endocrinologist recommended taking hormonal tests, but did not specify which indicators are required, it is important to find out exactly. If you have a clear understanding, the result will be as informative as possible, and you will not have to pay extra money for unnecessary tests.

Primary examination of the patient

If a patient visits an endocrinologist for the first time with complaints or for the sake of a preventive examination, it is necessary to investigate the following indicators:

TSH (thyroid stimulating hormone);

AT to thyroperoxidase (TPO).

This list will be enough to assess the general condition of the thyroid gland.

Suspicion of elevated hormone levels

If the patient has signs characteristic of an excess of thyroid hormones (hyperthermia, etc.), hyperthyroidism (thyrotoxicosis) must be ruled out.

In this case, the list of indicators for analysis will look like this:

TSH (thyroid stimulating hormone);

T4 St. (free tetraiodothyroxine);

T3 St. (free triiodothyronine);

AT to thyroperoxidase (TPO);

AT to TSH receptors (rTTH).

The latter indicator may most clearly indicate the presence of hyperthyroidism.

To monitor the effectiveness of treatment with thyroid drugs, the following are examined:

T4 free;

Analysis of other indicators is not required, since the figures remain the same during specific treatment or their dynamics is not of interest.

In the presence of nodular changes in the thyroid gland

If nodules are present in the thyroid gland, the initial blood test should include determination of the levels of the following substances:

TSH (thyroid stimulating hormone);

T4 St. (free tetraiodothyroxine);

T3 St. (free triiodothyronine);

AT to thyroperoxidase (TPO);

Calcitonin (tumor marker).

The latter indicator allows you to accurately determine the oncological diseases characteristic of the nodular form of goiter in the early stages.

During pregnancy

During pregnancy, the following are examined:

TSH (thyroid stimulating hormone);

T4 St. (free tetraiodothyroxine);

T3 St. (free triiodothyronine);

AT to thyroperoxidase (TPO).

It is important to keep in mind that in pregnant women, the level of TSH hormone is often below the designated standard. It does not indicate the presence of diseases or pathological processes.

If an operation was performed to eliminate a papillary or follicular tumor of the thyroid gland

It is necessary to make sure that the hormonal level and the level of specific proteins are normal in order to exclude the recurrence of cancer.

Researched:

TSH (thyroid stimulating hormone);

T4 St. (free tetraiodothyroxine);

AT to thyroglobulin;

thyroglobulin protein.

If surgery was performed to resect a medullary tumor

After such an operation, the following are examined:

TSH (thyroid stimulating hormone);

T4 St. (free tetraiodothyroxine);

Oncomarker calcitonin;

CEA cancer specific antigen.

When deciding whether to take tests for the concentration of thyroid hormones in the blood, you need to follow a small list of rules. They will increase information content and avoid unnecessary cash spending:

The concentration of antibodies to thyroperoxidase is examined once. Repeated blood donation to determine this indicator will not bring any information, since changes in the numerical value do not affect the dynamics of the course of the disease. A competent endocrinologist with this sign does not recommend taking such an analysis twice;

It is not possible to study free and bound thyroid hormones in the same assay. The result for both those and other indicators will be blurry. If you are strongly advised to complex analysis, this is simply a scam to increase your revenue;

Patients who have not been operated on for thyroid cancer should not be tested for thyroglobulin. This protein is examined only after removal of the thyroid gland and is a tumor marker of relapse. Even relatively healthy person the level of this protein may exceed the norm. It doesn't say anything. If a doctor or laboratory insists on including thyroglobulin in the analysis, this is a deceptive maneuver to extract money;

If the patient does not have a suspicion of hyperthyroidism, it is not worth examining antibodies to a thyroid-stimulating substance. This analysis is worth big money and should be taken strictly according to the testimony of a competent specialist in order to exclude thyrotoxicosis or assess the dynamics of therapy with confirmed thyroid hyperfunction;

Calcitonin is tested once. If no new nodes have appeared in the patient since the last check of the level of calcitonin in the blood, it is pointless to take this analysis. The same applies to the operation performed to remove the oncological neoplasm. Only these two cases are grounds for re-testing for calcitonin in order to exclude the appearance of tumors and relapse.

Norms of thyroid hormones in women

It should be noted that the uniform norms of hormones are long gone. Now the norm is determined depending on the type of apparatus on which the blood is examined, and the type of reagents used. For the "reference" figures taken figures recorded in international documents and agreements. Therefore, we can still talk about approximate numbers.

The norms of specific thyroid hormones and the pituitary hormone TSH are universal for both women and men. They are characterized by the same numbers.

Triiodothyronine (T3 hormone) in a free state

The study of this substance is associated with a number of technological difficulties and requires increased skill and attention from the personnel. If the technology is violated, the indicator may be unreasonably high. If there is doubt about the correctness of the result, the patient is assigned an analysis of the associated hormone (total T3).

The norm in modern clinics and laboratories is from 2.6 to 5.7 petamol / liter. Errors in the T3 study are very common.

An analysis is given general rule, once. Re-examination is required in a number of cases:

If the level of triiodothyronine exceeds the norm, and thyroid-stimulating hormone is within the normal range;

If the level of triiodothyronine is below normal, and thyroid-stimulating hormone is within normal limits;

If the level of triiodothyronine is below normal, and tetraiodothyronine is within normal limits.

Tetraiodothyronine (T4 hormone) in a free state

When analyzed in modern laboratories, its norm is in the range of 9.0-19.0 petamol / liter. Slight changes are possible in different institutions upper bound up to 3.0 units, but no more.

There are also many errors in this analysis. If the description of the laboratory study simultaneously contains a low level of tetraiodothyroxine, and the thyroid-stimulating hormone is normal, or vice versa, then the analysis is most likely carried out with violations. So the result is inaccurate. In this case, it is recommended to undergo the study again in another institution.

The norm of thyroid-stimulating hormone (TSH)

It has a normalized value on a global scale. Ranges from 0.39 to 3.99 micro-international units per milliliter. If the latest generation devices are used, the upper limit is increased by 1 unit.

When using the outdated ELISA method, the range in the description will be much lower (from 0.26 to 3.45). A high, up to half a unit, error is allowed, so it is better to retake the analysis in a modern clinic, moreover, at the same price.

Analysis for calcitonin

The norm of this substance is not strictly established. Each institution has its own. When carrying out the analysis, great accuracy is required, since even a small value, within half a unit, can indicate the initial and even advanced stage of the formation of a malignant tumor.

It is most reasonable to contact special endocrinological centers for stimulated analysis. With it, a calcium salt solution is injected intravenously, and after that, after a certain time interval, the value of the concentration of calcitonin in the blood is estimated.

Analysis for antibodies to thyroperoxidase

A strict norm is not established by international agreements or documents. The upper and lower limits vary from clinic to clinic. The study description sheet, the form of which is accepted by the laboratory, will define the range. It should be taken into account when evaluating the norm.

The most common standards are from 0 to 19-20 units or up to 120. This variation is due to the difference in devices and approaches to the study.

With a general primary interpretation (by the patient himself), several features should be borne in mind:

The degree of excess of the concentration of antibodies in the venous blood does not play a role. To assess the state of the endocrine system, the very fact that the indicator goes beyond the upper bar is important. Should not be addressed special attention and panic, even if the result is exceeded a thousand times;

A result that is within the range established by the laboratory is always considered normal. Various indicators, whether they are near the lower or upper limit, are absolutely equivalent. Even if the described result is only one less than the upper bar, this means that the indicator is normal. It is necessary to take into account this fact and not be afraid of a significant concentration if it fits into the normal range of numbers.

The degree of concentration of antibodies to thyroglobulin

In laboratories equipped with the latest generation of equipment, this indicator ranges from zero to 4.1 or 65 units.

There can be two reasons for the excess of antibodies to TG:

• Elevated or normal

  Increased or normal

  Dramatically reduced

  concentration is decreasing

  enlarged

  In the early stages, T3 and T4 are increased, with depletion of the thyroid gland, these indicators decrease sharply

  Elevated (in addition, antibodies to the TSH receptor are determined)

  enlarged

  Reduced or normal

  Reduced or normal

  Do not change

  Tables of indicators of thyroid hormones

  T3 hormone (triiodothyronine) total

  TK hormone (triiodothyronine) free

  T4 hormone (tetraiodothyroxine) total

  T4 hormone (tetraiodothyroxine) free

  TSH hormone (thyroid stimulating hormone)

  
  

  Interpretation TSH level:

  Less than 0.1 μIU / ml - thyrotoxicosis (suppressed TSH)

  From 0.1 to 0.4 μIU / ml - probable thyrotoxicosis (low TSH)

  2.5 to 4 µIU/mL is a high-normal TSH level

  0.4 to 2.5 µIU/ml - low-normal TSH level

  From 4.0 to 10.0 µIU/ml - subclinical hypothyroidism

  Over 10.0 μIU / ml - overt hypothyroidism

  Other hormones

  Hormone name	Designation	The normal value of the indicator
  TG (thyroglobulin)		< 54 нг/мл
  Antibodies to thyroglobulin
  Antibodies to thyroperoxidase		< 5,5 Ед/мл
  Antibodies to TSH receptors	AT-rTTG:
  	AT-rTTG: negative
  	AT-rTTG: doubtful	1.0 - 1.4 U/l
  	AT-rTTG: positive	> 1.4 U/l
  Antibodies to MAG (microsome fraction of thyrocytes)

  
  

  * LABORATORIES USING DIFFERENT RESEARCH METHODS MAY VARY RATES

  How to take a blood test for thyroid hormones?

  
  

  Often, patients who are about to donate blood for thyroid hormones turn to the Internet for help. There they expect to find general recommendations how to prepare for the study, and how the sampling procedure itself takes place.

  However, the network is replete with materials of extremely dubious content. Even with a cursory review, a knowledgeable physician will determine the inconsistency of most of the recommendations. The matter is aggravated by the wide circulation of such “articles”, since the sites copy materials from each other, only slightly altering the words, but leaving the essence.

  For example, it is often recommended to stop taking thyroid drugs a month before the test, and iodine-containing drugs a week before the test. Such information is fundamentally wrong, but an unknowing person will take it at face value.

  In fact, the patient needs to know and follow a number of simple rules:

  The level of all thyroid and related hormones does not depend on the diet in any way. The analysis can be taken both before and after eating. The concentration of these substances in the blood is stable;

  Hormonal tests can be taken at any time of the day. Although the concentration of thyroid-stimulating hormone varies depending on the time of day, the fluctuations in the indicator are so small that the morning and evening difference does not play a significant role;

  Cancel hormonal drugs may pose a risk to health and reduce the effectiveness of treatment. In many cases, it is against the background of conservative therapy that an analysis is carried out, the purpose of which is to determine the effectiveness of treatment and track the dynamics of the process. The only recommendation is not to take medication on the day of the study;

  During the menstrual cycle, the background of sex hormones changes, and not specific substances of the thyroid gland or pituitary hormones. No specific day of the cycle, including the period of menstruation, is not suitable for taking a blood test for the level of thyroid hormones, and also does not require special correction of the results.

  Deciphering the results of tests for thyroid hormones

  Deciphering the indicators obtained in the laboratory without the help of a specialist is a pointless and thankless task. Only a doctor can correctly and competently interpret the results of research. Independent actions in this direction lead patients to incorrect conclusions.

  In general, we can talk about some of the most common formulations and typical results. Indicators of the pituitary hormone TSH and specific thyroid-stimulating hormones must be interpreted systematically.

  If the TSH hormone is above normal

  This almost always means hypothyroidism (decreased thyroid function). As soon as the gland ceases to produce the level of active substances necessary for the normal functioning of the body, the pituitary gland secretes the stimulating TSH hormone.

  If, against the background of an increase in the pituitary hormone, tetraiodothyronine (T4) is below normal, we can talk about obvious hypothyroidism.

  There may be a situation in which T4 remains normal, then we are talking about a latent form of hypothyroidism.

  And in fact, and in another case, the thyroid gland works to the limit. However, if at the same time T4 is normal, the thyroid gland is in a euthyroid status, which can develop into more formidable diseases.

  With an increase in the level of TSH in a patient, the following are observed: clinical manifestations:

  Decreased psychomotor activity. The person looks lethargic and inhibited;

  Sleep problems (constantly want to sleep, no matter how long a person rests);

  Fragility of bones, nails and hair;

  Weakening of muscle tone.

  With euthyroid status, specialized therapy is not prescribed. All assistance to the patient comes down to constant monitoring of the development of the process. If it stops, no further action is required. If the level of T4 synthesis is below normal, replacement treatment with synthetic thyroid hormones is prescribed until the condition normalizes (from 7 months to a year).

  This picture of an erroneous result of the analysis is observed most often in people with existing or just preparing problems with the thyroid gland:

  If TSH is within the established normal indicators, and tetraiodothyronine is below normal. With almost one hundred percent probability, there is a research error. In 1% of cases, we can talk about or exceed the dosage of drugs for the treatment of diffuse toxic goiter;

  If TSH is within the allowable value, and triiodothyronine (T3) is below normal - a laboratory error;

  TSH is normal, T4 is also within the acceptable range, and triiodothyronine below the established level is a laboratory error;

  TSH is within the normal range, and thyroid hormones are above it - a laboratory error. This is simply impossible, since there are no objective reasons for the intensification of synthesis (there is no signal from the pituitary gland).

  Otherwise, if the thyroid-stimulating hormone is above the established norm, there is a situation of hyperthyroidism (thyrotoxicosis). If TSH deviates downward from the norm, and thyroxine is higher, we are talking about explicit hyperthyroidism. If specific hormones are within the limits of acceptable values, this is hyperthyroidism in a latent form. In all these cases, immediate medical attention is required.

  The only exception is pregnant women. During pregnancy, the level of thyroid-stimulating hormone may fall below the established mark. This is part of a natural physiological process that does not require close attention and treatment.

  What is the difference between the results of the analysis for free thyroid-stimulating hormone T4 during pregnancy?

  
  

  When it comes to endocrinological examination of a pregnant woman, the doctor should be especially careful. Hormonal background future mother changes significantly. This applies not only to sex, but also to pituitary and thyroid hormones.

  In the process of bearing a fetus, the level of thyroid-stimulating hormone, as a rule, decreases. The essence of this phenomenon is as follows: a special organ, the placenta, develops within the uterus. It is able to produce a specific active substance hCG (human chorionic gonadotropin). Its mechanism of action is similar to that of thyroid-stimulating hormone. It also stimulates more intensive production of thyroid active substances. Just for this reason, the synthesis of TSH falls. If the intensity of production of the pituitary active substance remains at the same level, the thyroid gland will release an excessive amount of thyroid hormones into the blood, hyperthyroidism will occur. For this reason, when assessing the degree of concentration of thyroid-stimulating hormone in the venous blood of a pregnant woman, a decrease in the level of TSH should be taken as the norm.

  During the period of gestation, this hormone is in an unstable state, and its synthesis depends on the intensity of hCG production. In this regard, the level of free tetraiodothyroxine (T4 hormone) becomes a particularly important indicator. It is for him that it is necessary to determine the presence of pathological processes with the thyroid gland in pregnant women.

  The classic picture of a normal pregnancy is that the pituitary thyroid stimulating hormone is below the established limit, free tetraiodothyronine is within the normal range.

  If thyroxine is outside the upper limit, but slightly, this can be considered as a variant of the norm. But the same may indicate the onset of thyroid disease. For clarification, it is necessary to conduct a complex of additional examinations.

  In the event that the level of T4 is significantly exceeded, and against this background there is an increase in the content of triiodothyronine in the blood (may be separately or both at once), treatment should be started immediately and the hormones should be brought back to normal.

  It makes no sense to assign a pregnant woman an analysis for bound (total) tetraiodothyronine. During gestation, the concentration of a special transport protein that binds the hormone increases. Therefore, this indicator will almost always be outside the normal range, but this increase will not have any diagnostic value. But the excess of the norm of TSH concentration during the period of gestation indicates serious problems. This situation can adversely affect both the health of the mother and the health of the unborn child.

  Exceeding the level of thyroid-stimulating hormone indicates a lack of thyroid substances. To make the thyroid gland work more actively, the pituitary gland sends a chemical signal to the organ. With prolonged excess of the level of TSH, the maternal iron may undergo diffuse and nodular changes. The organ will begin to change and grow in order to capture the required amount of iodine salts, but the degree of synthesis will not increase. The state of hypothyroidism will remain. The body of the child will also suffer, because nervous system led by the brain cannot form normally in conditions of a lack of iodine-containing hormones.

  According to research, pregnancy against the background of an extremely low concentration of specific substances of the thyroid gland most often ends in miscarriage. A child who was born against the background of a serious excess of TSH levels may be born with abnormalities mental development. However, this situation can be easily changed and the hormonal status of a pregnant woman can be brought back to normal by taking synthetic hormonal drugs.

  Sometimes doctors strongly recommend artificial termination of pregnancy due to imaginary threats to the intellectual development of the child. As statistics and medical practice show, in the 21st century it is almost impossible to give birth to a mentally handicapped child due to a lack of TSH. Under no circumstances should a pregnancy be terminated. The doctor who gives such recommendations is clearly not qualified enough.

  
  

  Thus, when conducting an analysis, the purpose of which is to evaluate general state thyroid gland, it is necessary to investigate not only specific substances, but also those that have a direct effect on the functioning of the organ: pituitary TSH hormone and antibody proteins. The thyroid gland performs a basic function necessary for the normal and stable functioning of the whole organism.

  Depending on the alleged disease, the tests vary. In one case, it is necessary to examine the blood for some antibodies, in the other case, for others. Some substances act as tumor markers, but donating blood to determine their level is worth it only in a few limited cases, and the results are interpreted ambiguously.

  The times of rationing indicators of hormonal blood tests are long gone. The norms are calculated by various clinics independently, based on the equipment used, chemicals and their own methodology. Therefore, in each clinic the result will be different. Trying to interpret results different clinics according to an equivalent principle, this is an empty case, since these indicators are not amenable to any recalculations.

  Some standards, from which specialists are repelled, still exist, and they are enshrined in medical documentation of a global scale. Only a doctor can correctly decipher and interpret the descriptions of laboratory tests. The patient himself runs the risk of making a mistake, misdiagnosing himself and causing great harm to his body by resorting to self-treatment.

  Testing for thyroid hormones does not require any preparation or special rules. All the information about this on the net is nothing more than a fiction or delusion of the average layman graphomaniac without a medical education. When referring a pregnant patient to an endocrinologist, it is important to remember that in this condition hormonal background changes dramatically, and requires a special approach to the study of blood.

  
  

  Education: Diploma of the Russian State Medical University N. I. Pirogov, specialty "Medicine" (2004). Residency at the Moscow State University of Medicine and Dentistry, diploma in Endocrinology (2006).

The thyroid gland is small, but it plays an important role in the body, like any organ of the human body. Thyroid symptoms are not always specific, but timely diagnosis allows to differentiate diseases with high accuracy.

Location

Associating deviations from the norm in their condition with the pathology of the thyroid gland, patients are wondering where the thyroid gland is located, since the diagnosis begins with this - with.

The gland is located under the larynx, at the level of the fifth or sixth cervical vertebra. It covers the top of the trachea with its lobes, and the isthmus of the gland falls directly into the middle of the trachea.

The shape of the gland resembles a butterfly with wings tapering upwards. The location does not depend on gender, in a third of cases there may be an insignificant additional part of the gland in the form of a pyramid, which does not affect its functioning, if present from birth.

In terms of mass, the thyroid gland reaches 25 grams, and in length no more than 4 cm. The average width is 1.5 cm, the same thickness. The volume is measured in milliliters and is up to 25 ml for men and up to 18 ml for women.

Functions

The thyroid gland is an endocrine organ responsible for the production of hormones. The functions of the thyroid gland are hormonal regulation through the production of a certain type of hormones. Thyroid hormones include iodine in their composition, since another function of the gland is the storage and biosynthesis of iodine into a more active organic function.

Gland hormones

Patients who are referred for laboratory diagnosis of thyroid diseases mistakenly believe that they are examining thyroid hormones TSH, AT-TPO, T3, T4, calcitonin. It is important to distinguish which hormones are produced by the thyroid gland, and which are other organs of internal secretion, without which the thyroid gland simply will not work.

• TSH is a thyroid-stimulating hormone that is produced by the pituitary gland, not the thyroid gland. But it regulates the work of the thyroid gland, activates the capture of iodine from the blood plasma by the thyroid gland.
• Ab-TPO is an antibody to thyroperoxidase, a non-hormonal substance produced by immune system as a result of pathological processes and autoimmune diseases.

Directly thyroid hormones and their functions:

• - T4 or tetraiodothyronine. Represents, is responsible for lipid metabolism, lowering the concentration of triglycerides and cholesterol in the blood, supports the metabolism of bone tissues.
• Triiodothyronine - T3, the main thyroid hormone, since thyroxine also tends to be converted to triiodothyronine by attaching another iodine molecule. Responsible for the synthesis of A, lowering the concentration of cholesterol, activation of metabolism, acceleration of peptide metabolism, normalization of cardiac activity.
• Thyrocalcitonin - is not a specific hormone, since it can also be produced by the thymus and. Responsible for the accumulation and distribution of calcium in bone tissue, in fact, strengthening it.

Based on this, the only thing the thyroid gland is responsible for is the synthesis and secretion of thyroid hormones. But the hormones produced by it perform a number of functions.

secretion process

The work of the thyroid gland does not even begin in the gland itself. The process of production and secretion, first of all, begins with the "commands" of the brain about the lack of thyroid hormones, and the thyroid gland implements them. The secretion algorithm can be described in the following steps:

• First, the pituitary and hypothalamus receive a signal from the receptors that the blood levels of thyroxine and triiodothyronine are low.
• The pituitary gland produces TSH, which activates the uptake of iodine by thyroid cells.
• Iron, capturing the inorganic form of iodine obtained from food, begins its biosynthesis into a more active, organic form.
• Synthesis occurs in the follicles that make up the body of the thyroid gland, and which are filled with a colloidal fluid containing thyroglobulin and peroxidase for synthesis.
• The resulting organic form of iodine is attached to thyroglobulin and released into the blood. Depending on the number of attached iodine molecules, thyroxin is formed - four iodine molecules, or triiodothyronine - three molecules.
• In the blood, T4 or T3 is released separately from globulin, and it is again captured by gland cells for use in further synthesis.
• The pituitary receptors receive a signal about a sufficient amount of hormones, the production of TSH becomes less active.

Accordingly, having detected signs of thyroid disease, the doctor prescribes a study not only of the concentration of thyroid hormones, but also of the hormones that regulate it, as well as antibodies to an important component of the colloid - peroxidase.

gland activity

At the moment, medicine divides all pathologies of the thyroid gland into three conditions:

• Hyperthyroidism is a dysfunction of the thyroid gland, in which secretion activity increases and an excess amount of thyroid hormones enters the blood, metabolic processes in the body increase. Thyrotoxicosis is also included in the disease.
• - a dysfunction of the thyroid gland, in which an insufficient amount of hormones is produced, as a result of which metabolic processes slow down due to lack of energy.
• - diseases of the gland, as an organ, which do not have any manifestations in the hormonal plan, but are accompanied by the pathology of the organ itself. Among the diseases, this includes goiter, nodular formations.

Thyroid diseases in women and men are diagnosed through, a decrease or increase in which indicates the reactivity or hypoactivity of the gland.

Diseases

In women, symptoms of thyroid disease appear more often, since hormonal fluctuations are reflected in the menstrual cycle, which makes the patient seek medical help. Men are more likely to attribute typical thyroid symptoms to fatigue and overexertion.

The main and most common diseases:

• Hypothyroidism;
• Nodular, diffuse or mixed goiter;
• Malignant tumors of the gland.

Each of these diseases is characterized by a special clinical picture and stages of development.

Hypothyroidism

This is chronic decline syndrome, which helps to slow down the body's metabolic processes. At the same time, the symptoms of thyroid disease may not make themselves felt for a long time, progress slowly, and disguise themselves as other diseases.

Hypothyroidism can be:

• Primary - at pathological changes in the thyroid gland;
• - with changes in the pituitary gland;
• Tertiary - with changes in the hypothalamus.

The causes of the disease are:

• Thyroiditis, coming after;
• iodine deficiency syndrome;
• Rehabilitation after radiation therapy;
• Postoperative period of removal of tumors, goiters.

Hypofunctional thyroid disease symptoms are as follows:

• Slow heart rate, heart rate;
• dizziness;
• pale skin;
• Chills, trembling;
• , including eyebrows;
• Swelling of the face, legs, hands;
• Voice changes, its roughness;
• constipation;
• An increase in the size of the liver;
• Weight gain despite decreased appetite;
• Loss of strength, emotional inertia.

Treatment of hypothyroidism is usually carried out by replenishing the lack of thyroid hormones in the body. But it should be understood that such treatment is advisable in a chronic case, which is diagnosed most often. If the disease is detected in the early stages, there is a chance to stimulate the work of the body by eliminating the root causes and temporarily taking another class of hormones.

This disease is called the lady's disease, since there are nine women for ten patients diagnosed. Excessive production of hormones leads to an acceleration of metabolic processes, excitation of cardiac activity, disturbances in the work of the central nervous system and ANS. Pronounced signs of the disease and the advanced form is called.

Reasons for the development of pathology:

• Syndrome, Plummer - goiters of an autoimmune or viral nature;
• Malignant tumors in the thyroid gland or pituitary gland;
• It may develop as a result of long-term treatment with arrhythmic drugs.

Often, the disease overtakes women after the onset of menopause due to hormonal imbalance, not being a consequence of tumors or goiters.

In this case, the main signs of thyroid gland in women:

• accelerated heartbeat;
• Atrial fibrillation;
• Humidity, hotness of the skin;
• Trembling of the fingers;
• Tremor can reach amplitudes, as in Parkinson's disease;
• Increased body temperature, fever;
• increased sweating;
• Diarrhea with increased appetite;
• Decrease in body weight;
• An increase in the size of the liver;
• Irritability, irascibility, insomnia, anxiety.

Treatment involves taking thyreostatics - drugs that reduce the activity of the secretion of thyroid hormones. Thyreostatics include drugs Thiamazole, Diiodothyrosine, as well as drugs that prevent the absorption of iodine.

In addition, a special diet is prescribed, in which alcohol, coffee, chocolate, hot spices and spices that can excite the central nervous system are excluded. Additionally, adrenergic blockers are prescribed to protect the heart muscle from harmful effects.

The disease has vivid symptoms - already from the second stage of goiter, the gland increases, which means that the entire neck area above the collarbone, where the thyroid gland is located, acquires distorted outlines.

• Timely detection of nodes, cysts, tumors of the thyroid gland;
• Determining the size of an organ;
• Diagnosis of deviations from the norm in size and volume.

Laboratory diagnostics involves the analysis of:

• AT-TPO;
• T3 - general and free;
• T4 - common and;
• Tumor markers for suspected tumor;
• General analysis of blood and urine.

In some cases, a biopsy of the tissues of the organ may be prescribed to clarify the diagnosis, if laboratory diagnosis was not enough. It is not recommended to independently interpret the results of the tests and make a diagnosis, since the norm of thyroid hormones is different for each gender, age, disease, influence chronic diseases. Self-treatment autoimmune and especially oncological diseases may result in a threat to health and life.

A thyroid hormone test is a study of the level of thyroid hormones (thyroxine and triiodothyronine) and the associated thyroid-stimulating hormone. The examination is prescribed by doctors of various specialties and today is the most popular of all hormone tests.

Why are these tests prescribed?

Analysis of thyroid hormones is relevant in practice:

The function of the thyroid gland affects the functioning of the cardiovascular, nervous, digestive, hematopoietic, and reproductive systems.

Thyrotoxicosis and hypothyroidism can mimic clinical picture other diseases. For example, "masks" reduced function thyroid gland are depression, obesity, chronic constipation, Iron-deficiency anemia, dementia, infertility, menstrual disorders, hearing loss, tunnel syndromes and other conditions.

Thyrotoxicosis must be excluded if tachycardia is detected, atrial fibrillation, arterial hypertension, insomnia, panic attacks and some other pathologies.

Indications for the analysis of thyroid hormones:

1. the presence of signs of thyrotoxicosis (tachycardia, extrasystole, weight loss, nervousness, tremor, etc.);
2. the presence of signs of hypothyroidism (bradycardia, weight gain, dry skin, slow speech, memory loss, etc.);
3. diffuse enlargement of the thyroid gland on palpation and according to ultrasound;
4. nodular formations of the thyroid tissue according to the examination and additional studies;
5. infertility;
6. menstrual irregularities;
7. miscarriage;
8. a sharp change in weight against the background of a normal diet and physical activity;
9. heart rhythm disturbances;
10. dyslipidemia (increased total cholesterol and atherogenic index);
11. anemia;
12. impotence and decreased libido;
13. galactorrhea;
14. delayed mental and physical development of the child;
15. control of conservative treatment for diseases of the thyroid gland;
16. control in postoperative period(subtotal resection, resection of the lobe, extirpation of the thyroid gland) and after radioisotope treatment.

In addition, the analysis for thyroid-stimulating hormone (TSH) is included in neonatal screening, that is, it is mandatory for all newborns in Russia. This study allows you to detect congenital hypothyroidism in time and start the necessary treatment.

How to properly prepare?

Thyroid hormones are influenced by many factors. In order to avoid mistakes in the study, it is important to properly prepare.

It is advisable to take all tests for thyroid hormones on an empty stomach. This means that at least 8 and no more than 12 hours should pass from the last meal. At this time, you can not drink sweet drinks, juice, coffee, tea, use chewing gum.

On the evening before the study, it is necessary to exclude the intake of alcoholic beverages.

Blood must be donated before 10 am.

Hormonal pills (L-thyroxine and others) can be taken only after taking blood for thyroid hormones.

Smoking must be stopped more than 60 minutes before blood sampling.

Before taking blood, the patient should rest (breathe) slightly for 10-15 minutes.

In the morning before the analysis, you can not undergo an X-ray examination, ECG, ultrasound or physiotherapy procedures.

Studies with X-ray contrast should be carried out no later than 2–4 days before blood sampling for analysis.

Deciphering the results of the analysis for thyroid hormones - the norms of the indicators in the table

Different laboratories may use different methods, units of measurement and reagents, and standards often differ accordingly.

Hypothyroidism and hyperthyroidism of the thyroid gland - abnormalities in the analyzes

Hypothyroidism is a decrease in thyroid function. In this condition, insufficient thyroid hormones are produced. Accordingly, in the analyzes, a decrease in free thyroxine (T4) and free triiodothyronine (T3) is observed. Quite often, the ratio of T3 and T4 increases (normally< 0,28).

Increased TSH- This is a normal reaction of the pituitary gland in primary hypothyroidism caused by a thyroid disease. Thyroid-stimulating hormone stimulates the work of thyrocytes. This indicator changes even with minor violations. Therefore, TSH rises in primary hypothyroidism even before T4 and T3 fall. These initial changes are interpreted as subclinical hypothyroidism.

Combination of low TSH and low thyroid hormones indicates secondary hypothyroidism. That is, about the low function of thyrocytes due to damage to the pituitary gland.

Decreased T3 and T4 without an increase in thyroid-stimulating hormone, it is evaluated as a laboratory effect and is interpreted as euthyroidism.

In hypothyroidism, markers of the autoimmune process, AT-TPO and AT-TG, are often detected. A high antibody titer helps to establish the cause of a decrease in thyroid function - autoimmune thyroiditis.

Treatment of hypothyroidism hormone replacement drugs (L-thyroxine and triiodothyronine) is controlled by the level of TSH. The target value for patients after surgery for cancer is below 1 µIU / ml, for pregnant women and women planning to conceive - up to 2.5 µIU / ml, for patients with myocardial ischemia - up to 10 µIU / ml, for the rest - 1-2, 5 µIU/ml.

hyperthyroidism- a state of excessive functional activity of the thyroid gland. In practice, the term thyrotoxicosis is often used.

With hyperthyroidism, the levels of T3 and T4 in the blood increase. There may be an isolated increase in only one of the hormones. T3 thyrotoxicosis is more common in elderly patients and is clinically manifested primarily by damage to the cardiovascular system.

Primary thyrotoxicosis manifested by a decrease in TSH. Thyroid-stimulating hormone can be suppressed to almost zero values. If this indicator is reduced, and T3 and T4 are within the normal range, then we can talk about subclinical thyrotoxicosis.

If high concentrations of thyroid hormones are combined with high TSH, the doctor may suspect secondary hyperthyroidism. This condition most often occurs with hormonally active pituitary adenoma.

Increased T3 and T4 without a decrease in thyroid-stimulating hormone evaluated as a laboratory effect and treated as euthyroidism.

In thyrotoxicosis, high antibody titers can be detected. In this case, the cause of the disease is most likely Graves' disease (diffuse toxic goiter).

Blood test for thyroid hormones during pregnancy

Pregnancy affects thyroid function and makes laboratory determination of thyroid hormones difficult.

The first trimester is characterized by a state of physiological thyrotoxicosis. TSH may be slightly below normal, and T3 and T4 may be elevated. These laboratory abnormalities occur in 20–25% of all women.

Throughout pregnancy, thyroid-stimulating hormone may remain suppressed or is at the lower limit of normal. Thyroid hormones (T3 and T4) may also be in the upper normal range or even slightly higher in a normal pregnancy.

Usually, a woman does not have any complaints or symptoms of impaired thyroid function. The condition does not require treatment.

With persistent, pronounced thyrotoxicosis, according to tests, signs of autoimmune damage to the thyroid gland and clinical manifestations, medical or surgical treatment can be prescribed.

Much more dangerous during pregnancy is low thyroid function. Hypothyroidism is diagnosed when TSH values ​​are above 2.5 µIU/ml in the first trimester and above 3 µIU/ml in the second and third.

The detection of elevated TSH during pregnancy requires the immediate administration of hormonal therapy (L-thyroxine). Hypothyroidism can lead to fetal malformations and abortion.

Where to get tested for thyroid hormones - prices in laboratories in Moscow and St. Petersburg

In state medical institutions in Moscow, St. Petersburg and other cities of Russia, it is possible to determine the hormones TSH, T3, T4, thyroglobulin and antibodies. However, unfortunately, in most cases, funding for laboratory diagnostics is insufficient.

Tests for thyroid hormones can be taken at any paid laboratory. These popular examinations are performed quickly and with high accuracy.

In Moscow, the most specialized institution is the laboratory of the Endocrinological Research Center. The cost of TSH analysis in the Center is 460 rubles, T3 - 550 rubles, T4 - 460 rubles, AT-TPO and AT-TG 490 and 450 rubles, respectively.

There are dozens of private medical centers in St. Petersburg that provide blood sampling services for analysis. You can donate TSH, T4, T3, thyroglobulin and antibodies at the clinics of the North-West Endocrinology Center, Globus Med, Helix Laboratory Service, ABIA and many others. Prices for one study - from 340 rubles.

The thyroid gland plays a special role in the human body. This is a small organ that is located on the front wall of the neck, has the shape of a butterfly, consists of two lobes and an isthmus, despite its small size, performs many functions and controls the work of almost all organs and systems.

Today we will try to tell you what function the thyroid gland performs, what it is responsible for and how the imbalance in its work affects the general condition of a person.

Thyroid functions

The main function of the thyroid gland is the production of hormones that maintain normal metabolism throughout the body. The body produces two main hormones - thyroxine and triiodothyronine, as well as the hormone calcitonin, produced by C-cells of the thyroid gland.

Hormones are involved in stimulating metabolism throughout the body and affect the functioning of many organs. Therefore, the main functions of the thyroid gland are:

The thyroid gland and its role in women's health

The thyroid gland plays a special role in the body of a woman. Its reproductive function directly depends on the correct production of hormones.

When any malfunctions occur and its function is disturbed, women experience menstrual irregularities, diseases of the reproductive system and mammary glands often develop, and problems with conception arise. Moreover, the normal functioning of the thyroid gland in women ensures the proper development of the fetus. It has been proven that with a low hormonal background in a pregnant woman, in the future, the child will have a delay in physical and mental development.

Dysfunction of the thyroid gland is a serious blow to the body, dysfunction of the organ can affect the development of various diseases. First of all, the metabolism is disturbed, thereby malfunctioning in the work of many organs and systems. The most common causes of this condition are: lack of iodine, hormonal changes, regular stress, especially in women, taking certain medications, as well as various kinds of diseases of the pituitary gland of the brain, etc. For the most part, various kinds of disorders of the gland affect women, men are susceptible these diseases are much rarer. The consequences of dysfunction can be indicated by such pathologies:

Of course, the thyroid gland plays an important role in maintaining the body in a healthy state, so it is necessary to carefully monitor its proper functioning.

Until a certain point, many people do not think about the fact that there is such an organ in their body, and where the thyroid gland is located. Even if some uncomfortable symptoms occur, not everyone will attribute them to the state of the thyroid gland. Meanwhile, many diseases are associated precisely with a violation of the function of this organ.

The thyroid gland is an endocrine organ that produces hormones that control all energy flows in our body. It is inextricably linked with the hypothalamus and pituitary gland, significantly affecting their functioning. At the same time, there is also a feedback - these parts of the brain control the work of the gland.

The thyroid gland is located on the neck on the sides of the trachea in the region of 2-3 rings above the larynx. In shape, it resembles a butterfly with wide and short lower "wings" and high, slightly elongated upper ones.

The structure of the thyroid gland in proportion is 4x2x2 cm, and the thickness of the isthmus does not exceed 5 mm. Any deviation from these parameters may indicate pathological processes taking place in the organ.

Anatomically, the thyroid gland consists of connective tissue, in the thickness of which there are follicles - very small vesicles, on the inner surface of which there are follicular cells (thyrocytes) that produce hormones. The function of the thyroid gland depends on them. All connective tissue is permeated with blood and lymphatic vessels, nerve ganglia.

The location of the thyroid gland does not depend on gender, that is, in men and women it is located in the same place.

The principle of operation and the role of the thyroid gland

The normal functioning of the thyroid gland is a very complex process that is controlled and stimulated by the pituitary gland and hypothalamus. The state of energy exchange processes in the body depends on the interaction of these organs.

The mechanism of this system is as follows:

• if it is necessary to enhance metabolic processes, a neural signal enters the hypothalamus;
• there is a synthesis of thyrotropic releasing factor, which is sent to the pituitary gland;
• in the pituitary gland, the production of thyroid-stimulating hormone (TSH of the thyroid gland) is stimulated;
• TSH activates the production of hormones directly by the thyroid gland (T3 and T4).

The thyroid gland's own thyroid hormones (T3 and T4) are in the body in a state "bound" to other proteins, and therefore inactive. Only after a signal from the thyroid gland are they released and take part in metabolic processes.

Types of thyroid hormones - TSH (thyroid-stimulating hormone), T3 - (triiodothyronine), T4 (thyroxine), calcitonin.

Own thyroid hormones are responsible for certain processes in the human body, their functions extend to all organs and systems. The thyroid gland is called one of the most significant endocrine glands, which "conducts the work" of the whole body.

So what is the thyroid gland and the thyroid hormones produced responsible for?

T3 (triiodothyronine) and T4 (thyroxine) are responsible for all metabolic processes (energy and material), control the growth and development of organs and tissues, including the central nervous system. They take an active (if not key) part in the breakdown of fats, the release of glucose, and the processes of assimilation of protein compounds. Their level affects the concentration of sex hormones during sexual development, the ability to conceive and bear a child and for its intrauterine development.

Regulates the cellular metabolism of calcium and phosphorus, which affects the growth and development of bone tissue, the human skeleton. With any bone defects (fractures, cracks), it is this hormone that helps calcium “mount” in the right place and stimulates the production of osteoblasts that produce new bone tissue.

The functions of the thyroid gland are based on the proper functioning of this organ, the activity of which affects all processes in the human body.

Thyroid dysfunction

Disturbances in the work of the thyroid gland can be conditionally divided according to the degree of functional activity.

• Euthyroidism is a state of the gland in which it produces a sufficient amount of hormones, while all organs and systems of the body work without failure, in normal mode. The pathology of the thyroid gland is directly related to the state of the organ itself.
• Hypothyroidism (deficiency syndrome) - thyroid hormones of the thyroid gland are produced in insufficient quantities, which affects the work of all controlled organs. There is an energy deficiency.
• (overabundance syndrome) - the functions of the thyroid gland are impaired due to increased production of hormones, which causes excessively active metabolic processes in the body.

The functional activity of the thyroid gland is regulated by the normal level of thyroid-stimulating hormone produced by the pituitary gland. The deviation of its quantity from the norm in one direction or another indicates that thyroid hormones are produced in larger or smaller quantities, and this causes pathological conditions.

However, not only thyroid hormones cause thyroid diseases. Modern medicine classifies:

• autoimmune;
• malignant diseases;
• goiter of various etiologies;
• and some others, more rare.

The first symptoms of thyroid disease

Disruption of the thyroid gland has its own symptoms, which, however, very often pass without proper attention. Everything is attributed to banal fatigue, stress, overwork, or the consequences of a recent cold. But is it always like this?

It cannot be said that the first signs of thyroid disease were so specific:

• decreased vitality, fatigue even with minor loads;
• irritability, nervousness, causeless mood swings;
• weight loss or weight gain with a normal diet;
• the skin and hair are dry and dull, the nail plates exfoliate and crumble;
• muscle pain for no apparent reason;
• thyroid diseases in women can give hormonal disruptions - irregular, too plentiful or meager periods;
• thyroid disorders in children can cause hyperactivity.

If you notice several of these symptoms in yourself, it makes sense to contact a specialist and conduct an examination that will tell you what your thyroid gland produces and the presence of pathological processes in it. Symptoms of thyroid disease are almost invisible in the early stages. But still, with palpation, people themselves can detect some changes.

Visible enlargement of the thyroid gland occurs in fairly advanced and severe cases. In the normal state, the gland is not visible and not palpable.

• 1 degree - palpable without visible effort, but not visually noticeable;
• Grade 2 - palpable and visible to the eye when performing swallowing movements;
• Grade 3 - there is a “fat neck” syndrome, which is visible to the naked eye, but it happens that such a symptom does not really bother the patient (sometimes the thyroid gland hurts in such conditions);
• 4 degree - the physiological outlines of the neck change;
• Grade 5 - a pronounced deformation of the neck, which causes discomfort to the patient, since the thyroid gland hurts quite strongly.

The first two degrees of increase can be caused by physiological characteristics. In particular, girls may experience some deviations during menstruation, especially during puberty.

In women, iron may increase slightly during pregnancy and lactation, as hormonal changes occur in the body.

Diagnostic methods

Methods for diagnosing pathology are based not only on what hormones the thyroid gland produces. There is a whole range of measures that make it possible to make a diagnosis and prescribe adequate treatment.

• Medical examination. As a rule, the primary examination is carried out by the therapist and prescribes laboratory tests based on the patient's complaints.
• The obligatory diagnostic minimum is a general blood test and a general urinalysis.

• Determination of the level of basic energy metabolism. Such an analysis is carried out using special devices and in compliance with certain rules. Often this study is done in a hospital setting.
• Biochemical analysis of blood - the so-called "renal and liver tests", which give an idea of ​​​​the work of organs that may suffer due to thyroid dysfunction.
• Determination of the level of cholesterol in the blood. However, this method cannot be recognized as one hundred percent, as it has age-related features. As a rule, in older people, this indicator may change due to the presence of age-related diseases (atherosclerosis). But for children, it will be more informative.
• The duration of the Achilles reflex is an affordable, simple and painless additional diagnostic method that may indicate a disease.

• Ultrasound of the gland makes it possible to identify morphological changes, an increase in parameters and the presence of nodular or tumor formations.
• X-ray examination is an excellent way to diagnose signs of thyroid disease in pediatric patients. Examination is carried out not only of the gland itself, but also of bone tissues (thorax, hands) to determine the “bone age”, which in children can be located far beyond the passport age, depending on various diseases.
• CT (computed tomography) and MRI (magnetic resonance imaging) make it possible to determine the location of the thyroid gland, the presence of inclusions, the degree of enlargement and the presence of nodes - possible pathologies of the anatomy of the thyroid gland.

• When diagnosing thyroid diseases, the symptoms of iodine deficiency are determined by identifying the amount of iodine associated with blood proteins.
• Analysis for thyroid hormones of the thyroid gland (thyroxine, triiodothyronine, thyroid-stimulating hormone).

Some additional studies are carried out strictly according to indications and based on the severity of the patient's condition, as well as taking into account the age and general condition of the person.

Thyroid hormone levels

Only a specialist can know everything about the thyroid gland. But everyone has the opportunity to navigate the most elementary laboratory indicators.

It should also be noted that thyroid diseases in women are observed more often than in men, and the symptoms of thyroid disease in women are somewhat different from those in men.

Table of norms of thyroid hormones in women.

The figures may vary slightly, as different laboratories may use different methods of analysis. The norm of thyroid hormones in women also depends on the monthly cycle and other physiological conditions.

If more or less hormones are produced, do not despair. Thyroid dysfunction is treatable, especially if you see a doctor in a timely manner. Prescribing the necessary drugs, some change in diet and regular monitoring of laboratory parameters - the dysfunction syndrome will be canceled or at least brought under control.

Causes and prevention

Signs of a thyroid disorder, or thyroid dysfunction syndrome, do not appear out of nowhere. There are a number of reasons for this:

• Heredity. If you have discovered the first signs of an enlarged thyroid gland or other alarming symptoms, find out if any of your relatives suffered from thyroid diseases.
• Stress. Perhaps the most common cause of such endocrine pathologies today, the most common of which is Shahimoto's syndrome. In this state, the brain literally "forces" your body to produce antibodies that attack your own thyroid gland, causing very unpleasant symptoms, and it stops producing enough hormones.
• Unfavorable ecology. The impact of environmental factors has an extremely negative effect on the work of all endocrine glands.
• Nutrition. Insufficient amount of iodine in water and air, deficiency of selenium and fluorine, which play a fundamental role in the functioning of the thyroid gland. The presence of GMOs, food additives, stabilizers and other "chemistry" in food products also negatively affect the state of health, including the endocrine system.

These are the most common causes of thyroid symptoms that work with disorders in both men and women. Naturally, children suffer to no lesser extent from congenital and acquired pathologies.

In order to prevent, you should introduce more fish and seafood, fresh vegetables and fruits, juices, and clean water into your diet. If possible, replace sugar with honey (if there is no allergy to bee products), eat cereals, whole grain bread.

• smoked meats;
• hot spices;
• fried foods.

The only exception is lean meat cooked over an open fire. Canned foods are also not very “liked” by the thyroid gland. Carbonated drinks, alcohol (including weak). But natural red wine in limited quantities has a very good effect on the hematopoietic system and the functioning of the thyroid gland.

The most important thing is not only to listen, but also to hear the signals of your body. Nature is wiser than us, and if she gives a sign, be able to find the “cipher” and “read” it correctly. The thyroid gland masks its symptoms, but they can be noticed.

Deals with issues of prevention, diagnosis and treatment of diseases of the endocrine system: thyroid gland, pancreas, adrenal glands, pituitary gland, gonads, parathyroid glands, thymus gland, etc.