Blood test for TSH hormone - check the thyroid gland

Blood analysis

testing the concentration
of the hormone TSH
is a mandatory part of a comprehensive examination, which is prescribed by a doctor if a patient is suspected of having thyroid disease.
A blood test for the hormone TSH is the most important study in endocrinology. Click to make an appointment, ultrasound or tests
DETAILED DESCRIPTION OF BLOOD TEST FOR TSH HORMONE

If the level of thyroid-stimulating hormone is outside the normal range (decrease or increase), which will be shown in the results of the study, it will allow the specialist to confirm the presumptive diagnosis or make one.

General information about TSH

The content of the article

Thyroid-stimulating hormone is produced by a small gland located on the lower surface of the brain - the pituitary gland. It controls the formation of thyroid hormones (T3, T4) using feedback technology, ensuring a stable concentration of these substances in the blood. Thyroid hormones are considered the main controllers of energy expenditure that occurs in the human body. Maintaining their normal levels is very important for the healthy functioning of almost all systems and organs.

Why is a blood test for the hormone TSH performed?

A doctor may order a patient to take a thyroid-stimulating hormone blood test in the following situations.

• The need to check the condition of the thyroid gland, suspicion of the development of diseases associated with this organ in a person.
• The need for control over the treatment of thyroid diseases.
• To identify female infertility and select the optimal treatment method for this problem.

A blood test for the hormone TSH can be prescribed by a gynecologist or endocrinologist.

Norm T3 and T4 and interpretation of the analysis

Since the level of triiodothyronine and thyroxine is determined simultaneously with the study of TSH, and they are all interconnected, it is important to know the normal values ​​​​of these two hormones.

The T3 content in the blood of an adult should be in the range from 1.08 to 3.14 nmol/l. As for thyroxine, the values ​​for men and women are different. For men, the norm is a level from 59 to 135 nmol/l, for women the figure is slightly higher - from 71 to 142 nmol/l.

Deviations from the norm indicate existing pathologies. If T3 is elevated, the reasons may be:

• hyperthyroidism;
• thyroid adenoma;
• Pendrer's syndrome (a genetic disease characterized by vestibular disorders, bilateral hearing loss and goiter);
• chronic liver pathologies;
• choriocarcinoma;
• nephrotic syndrome.

Triiodothyronine is reduced in the following cases:

• iodine deficiency;
• hypothyroidism;
• adrenal insufficiency;
• significant physical activity;
• weight loss.

Deviations from the norm of the T4 hormone are due to the following reasons:

• increase: thyrotoxic adenoma, nephrotic syndrome, decrease in thyroxine-binding globulin;
• A decrease in the hormone is usually associated with diseases of the thyroid gland.

Test results can be indirectly influenced by factors such as severe stress and taking oral contraceptives.

Indications for TSH analysis

As a rule, the doctor recommends that the patient take a blood test for the TSH hormone

with an increase in the size of the thyroid gland, in the presence of signs of hypothyroidism, hyperthyroidism.

Symptoms of hyperthyroidism may include:

• increased anxiety;
• cardiopalmus;
• reduction in body weight;
• hand trembling;
• insomnia;
• fatigue, chronic weakness;
• intolerance to bright light;
• diarrhea;
• dryness, swelling around the eyes, bulging, hyperemia;
• reduction in visual acuity.

Also, a TSH test must be performed if a patient has signs of hypothyroidism:

• constipation;
• dry skin;
• cold intolerance;
• hair loss;
• increased fatigue, constant weakness;
• disruptions of the menstrual cycle (in female patients).

Studying the level of thyroid-stimulating hormone in the patient’s body is a mandatory element of monitoring the effectiveness of the chosen treatment for thyroid diseases. TSH levels can also be checked in newborn infants if they belong to a risk group. A blood test for the TSH hormone is not performed for children at the Diana Clinic - it must be done in a children's clinic!

What the results say

The norm values ​​depend on what indicators are used in a particular laboratory, therefore the interpretation

Only a doctor can
review test results The test may show an abnormal decrease or increase in the patient's TSH level.

Test results for the thyroid-stimulating hormone TSH may fall below normal in the following situations:

• cachexia;
• hyperthyroidism in pregnancy;
• mental illnesses, deviations;
• autoimmune thyroiditis with signs of thyrotoxicosis;
• Plummer's disease (thyrotoxic adenoma);
• TSH-independent thyrotoxicosis;
• diffuse toxic goiter.

Also, TSH levels may increase, exceeding the norm. Elevated

TSH test
results may indicate that the patient has the following problems:

• preeclampsia;
• mental illnesses, disorders;
• lead poisoning;
• adrenal insufficiency;
• lung tumors (thyrotropin-secreting);
• secondary or primary hypothyroidism;
• syndrome of unregulated secretion of thyroid-stimulating hormone;
• Hashimoto's thyroiditis;
• pituitary tumor (basophilic adenoma, thyrotropinoma).

An increase and decrease in thyroid-stimulating hormone levels indicates a malfunction of the patient’s thyroid gland. However, it is often not possible to accurately and correctly determine the cause of deviations using only a single analysis of the degree of concentration of TSH in the body. Therefore, along with this study, doctors often recommend that patients undergo tests for

triiodothyronine (T3), thyroxine
(T4).

How much does a TSH test cost?

Price

Testing
for thyroid-stimulating hormone
depends on the laboratory in which it is taken. At the Diana Clinic, a blood test for TSH without taking into account the cost of the discount is:

The cost of tests for other hormones can be found in the price list HERE. In the section “Blood Hormones”.

ADDITIONAL SERVICES AND ANALYSIS FOR TSH HORMONE ANALYSIS

What can affect the analysis results

As part of proper preparation for the test

blood test for TSH, the patient is obliged to exclude factors that can distort the results and lead to their incorrect
interpretation.

• The level of concentration of the TSH substance in the body reflects the picture in the “thyroid gland – pituitary gland” system on average over the last 5-6 weeks. Therefore, control diagnostics of thyroid-stimulating hormone levels in the blood should be carried out 2 months after the dose of drugs that can change the level of hormones is adjusted. Of course, such adjustments are made together with the attending physician.
• of TSH
  in the body exceeding
  the norm
  in the
  analysis
  results: atenolol, motilium, phenytoin, valproic acid, amiodarone, propanolol, prednisolone, as well as methimazole, lovastatin, rifampicin, metoclopramide, iodides, and so on. The advisability of refusing them must be discussed with your doctor.
• The level of concentration of the hormone TSH in the body can change if the patient experiences emotional shock or severe stress. Also, indicators may be distorted due to serious physical activity.
• Infectious diseases that the patient has recently suffered can change the indicators of this substance. You must notify your doctor about this.
• The concentration of TSH in the body may vary throughout the day. Therefore, if thyroid-stimulating hormone concentrations are being monitored, it is important to test for TSH hormone
  at the same time of day.
• If the purpose of the analysis is to monitor the effectiveness of the therapy, taking medications prescribed by the doctor is suspended immediately on the day of the study.
• TSH levels can increase in women in the third trimester of pregnancy.

MEDICAL CENTER

A pituitary hormone that regulates the functions of the thyroid gland. One of the most important tests in the laboratory diagnosis of thyroid diseases. .

TSH is a glycoprotein with a molecular weight of about 28 kDa. Synthesized in the anterior lobe of the pituitary gland. Activates the production and secretion of thyroid hormones (thyroid hormones), initiates cell growth and mitotic activity of thyroid cells. Synthesis and secretion of TSH are stimulated by thyrotropin-releasing hormone of the hypothalamus in response to a decrease in the level of circulating thyroid hormones. The level of TSH is in an inverse logarithmic relationship with the concentration of T4: as the level of T4 increases, the production of TSH decreases; as the level of T4 decreases, the production of TSH compensatory increases, which helps maintain the concentration of thyroid hormones at the required height. TSH secretion is influenced by various neuronal mechanisms and changes during sleep, low temperature, and nonspecific stress. TSH is characterized by daily fluctuations in concentration: blood TSH reaches its highest values ​​at 2-4 a.m., high levels in the blood remain until 6-8 a.m., and minimum TSH values ​​occur at 5-6 p.m. The reference values ​​for TSH levels given below are applicable for outpatients in the period from 8 to 18 hours. The normal rhythm of thyrotropin secretion is disrupted when awake at night.

With clinically pronounced primary hypothyroidism (i.e., damage at the level of the thyroid gland, which leads to a decrease in its function), there is a significant increase in the level of TSH against the background of low levels of thyroid hormones. Primary hyperthyroidism, in contrast, is associated with decreased or undetectable TSH levels and high thyroid hormone levels. Determination of TSH levels makes it possible to identify subclinical stages of thyroid diseases, when the concentration of thyroid hormones is still maintained by regulatory mechanisms within the reference values. Typically, when screening for thyroid function, TSH is used as the only test or in combination with the determination of free T4.

Taking thyroxine preparations on the eve of taking blood for testing does not affect the concentration of TSH. Normalization of TSH levels during replacement therapy for hypothyroidism with L-thyroxine drugs occurs slowly (over several weeks and months), since in chronic severe hypothyroidism hyperplasia of thyrotrophs develops. The paradoxical combination - a high level of TSH and a high level of free T4 - during this period is an artificially induced (iatrogenic) condition. It is advisable to carry out repeated studies of TSH levels in order to monitor therapy no earlier than 6 weeks after changing the dose or type of drug.

In secondary and tertiary hypothyroidism associated with pituitary dysfunction due to pathology of the pituitary gland and hypothalamus, significantly reduced levels of T3 and T4 are combined with normal or slightly increased levels of TSH, which in these cases has reduced biological activity. Rare clinical cases of secondary hyperthyroidism may be due to TSH-secreting tumors.

Severe diseases not associated with thyroid pathology can cause a temporary change in TSH concentration. The cause may be the use of medications or the consequences of the disease itself. Typically, there is a decrease in TSH levels during the acute phase of the disease and a slight increase in levels during recovery. If necessary, in such cases, it is advisable to focus on the extended reference range of TSH (0.02-10 mU/l) and use a set of tests for TSH and T4 (or free T4).

Physiological changes in TSH concentrations are observed during pregnancy. High concentrations of human chorionic gonadotropin, which has a certain structural similarity to TSH, can have a stimulating effect on the synthesis of thyroid hormones. In the first trimester of pregnancy, a temporary increase in T4 levels and a decrease in TSH levels are observed. During the second and third trimesters, TSH levels return to normal. An elevated TSH level in early pregnancy may indicate latent maternal hypothyroidism, which is potentially dangerous for the development of the fetus.

Limits of determination: 0.0025 mU/l-100 mU/l

Other important rules for preparing for a blood test for the TSH hormone

• It is highly advisable to donate blood for any hormonal analysis, including TSH, in the morning, always on an empty stomach. If it is not possible to submit biological material for research in the morning, this must be done at least 5 hours after eating.
• It is recommended to establish physical and psycho-emotional comfort a day before blood sampling. You can’t play sports (even light ones) or be nervous.
• Doctors do not recommend visiting a bathhouse or sauna or taking a hot bath in preparation for a thyroid-stimulating hormone test; overheating can distort the results of the study. Hypothermia is also prohibited, so activities such as going winter fishing or swimming in an ice hole are not allowed.
• 48 hours before the test, avoid drinking alcoholic beverages. Ideally, you should refrain from smoking for 24 hours before the test; if this is difficult, you should not smoke for 2-3 hours before taking blood.
• It is not recommended to donate blood for laboratory analysis immediately after an instrumental examination, physiotherapeutic procedures, ultrasound and x-ray examinations, massage and other medical procedures.

A blood test for the TSH hormone can only be taken in a good clinic!

Preparation for the procedure

It is extremely important to know how to take a TSH test , since taking preparatory measures will allow you to obtain the most reliable data. Preparation includes:

1. 3 days before blood sampling, you need to give up alcoholic beverages, smoking, playing sports, and refrain from stress and temperature changes.
2. Stop drug therapy (if possible and approved by your doctor).
3. Before the procedure, do not have breakfast, maximum - a glass of still water. It is recommended to refrain from eating any food 12 hours before the test.

Before the TSH test

It is advisable to come to the laboratory about an hour or at least half an hour before taking blood. The patient should sit, rest, and relax. Concurrent testing for T4 hormones may be required.

T3 together with
TSH
in order for the doctor to obtain a complete picture of the disease; the rules for preparing for these studies are almost the same.

Women can donate blood for TSH, regardless of the phase of the menstrual cycle, unless otherwise indicated by the attending physician. About how soon a hormone test is done,

can be obtained from the specific laboratory.

How the research is carried out

Taking a TSH test is a universal procedure that does not require special medical instruments or equipment. It is carried out in all clinical laboratories (both paid and public). It is recommended to donate blood in the morning (from 8 to 11 am). The TSH concentration is determined using a chemiluminescent immunoassay on microparticles, which has a high level of accuracy. For this purpose, blood serum obtained from the patient’s vein is used. The procedure itself does not cause severe pain, but may be accompanied by minor discomfort. As a rule, you can get results within 1-2 business days. It is important to understand that the patient receives exclusively diagnostic data, without interpretation and diagnosis. This is done exclusively by the attending physician. If the TSH test is normal , then WHO recommends conducting the next examination no earlier than in a year. If there are problems with the thyroid gland, the frequency of the procedure should be increased to 2 times a year. You can get a TSH test at the medart clinic.

How to decipher a TSH analysis

Thyroid-stimulating hormone is known as the main regulator of the thyroid gland; if a patient is suspected of having a disease associated with it, a test for it is required. The interpretation of the analysis results should be done by a specialist, but knowledge of the basic values ​​of the norm will allow the patient to independently gain an understanding of his problem.

How to prepare?

A little preparation is required before taking laboratory tests:

1. Blood should be donated in the morning (from 8 to 10) on an empty stomach. The last meal is no later than 12 hours before the procedure.
2. The day before, cancel physical activity, give up alcohol and smoking.
3. It is advisable to come to the laboratory in a calm psycho-emotional state, without hypothermia or overheating.
4. During the first examination, you need to stop all medications that affect the functioning of the thyroid gland two to four weeks before the procedure.
5. During a control analysis carried out to assess the effectiveness of treatment, stop taking medications on the day of the study.
6. Report the use of corticosteroids, aspirin, tranquilizers, and oral contraceptives.

How to interpret blood tests for the hormone TSH

Norm of the hormone TSH

test
results do not depend on the gender of the patient. However, the indicators vary depending on the norm, and the presence of pregnancy and trimester also have an impact. Normal results for each age group are indicated in µIU/ml.

• The normal level of thyroid-stimulating hormone for newborn babies is 0.7-15.2.
• Normal values ​​for children aged 6 days - 3 months are 0.72 - 11.0.
• For children aged 4-12 months, the normal concentration of TSH in the body can be 0.73-8.35.
• Normal values ​​of thyroid-stimulating hormone for children from one to six years old are in the range of 0.7-5.97.
• If a child is aged 7-11 years, normal levels of the TSH hormone for him are 0.6-4.84.
• For adolescents aged 12-18 years, the normal concentration of this substance in the body is 0.5-4.3.
• For people over 18 years of age, the normal levels of thyroid-stimulating hormone are in the range of 0.27-4.2.

Complexes with this research

Advanced anti-aging diagnostics in postmenopause Advanced monitoring of age-related changes during postmenopause 22,480 ₽ Composition
Fitness monitoring Examination for choosing physical activity and monitoring the state of the body 4,480 ₽ Composition

Fitness control of sports nutrition Assessment of liver function, hormone levels and metabolism when taking sports nutrition RUB 3,290 Composition

IN OTHER COMPLEXES

• Female hormones. Follicular phase RUB 3,990
• Metabolic profile RUB 4,170
• Women's check-up No. 1 RUB 13,430
• Advanced male anti-aging diagnostics RUB 25,520
• Check-up No. 1 for children and teenagers 7,140 RUR

Interpretation of tests and pregnancy

The level of concentration of thyroid-stimulating hormone in the female body may change due to pregnancy, which must be taken into account when interpreting the results of a blood test for TSH.

• Normal TSH levels before the 12th week of pregnancy are 0.35 – 2.5 µIU/ml.
• The level of this substance in the blood of a pregnant woman at 12-24 weeks of pregnancy is in the range of 0.35 - 3 µIU/ml.
• At 24-42 weeks of pregnancy the indicators are similar – 0.35 – 3 µIU/ml. During this period, it is also possible that the results will be slightly higher than normal.

Thyroid-stimulating hormone: normal

Normal TSH directly depends on the person’s age. For each age period, this value has different indicators, which is noticeably visible in the first months after birth. Reference values ​​are:

As can be seen from the table, changes in normal TSH levels vary throughout life. Therefore, only a medical professional must make a conclusion based on the results of the analysis, comparing them with the norm. When deciphering, the endocrinologist can also take into account the characteristics of each organism, gender (according to statistics, women develop thyroid problems 2 times more often than men), a history of diseases, medications taken, and much more.

What does an elevated TSH mean?

If the indicators obtained as a result of a blood test for TSH

, exceed the norm, this may indicate that the patient has serious illnesses. The concentration of thyroid-stimulating hormone may increase in the following cases:

• pituitary tumor (for example, basophilic adenoma, thyrotropinoma);
• primary, secondary hypothyroidism;
• syndrome of unregulated secretion of the hormone TSH;
• Hashimoto's thyroiditis;
• adrenal insufficiency;
• lead poisoning;
• preeclampsia;
• thyrotropin-secreting lung tumors
• mental disorders, diseases.

It must also be remembered that the TSH

in the body may increase in the
test
results if the patient takes the following drugs as part of treatment: rifampicin, diphenin, methimazole, iodides, furosemides, metoclopramide, aminoglutethimide, benserazide, phenothiazine derivatives, morphine, prednisolone, calcitonin, as well as amiodarone, propranolone, valproic acid , metoprolol, motilium, clomiphene, atenolol and phenytoin.

Why is TSH low?

A decrease in TSH concentration in the blood may indicate:

• Deterioration of the pituitary gland function – after brain injuries, with hereditary diseases, infections, after severe bleeding;

• Hypothyroidism is a deterioration in the normal functioning and function of the thyroid gland, which may be associated with a tumor, iodine deficiency, protein deficiency, heredity, exposure to radiation and other reasons;

• Psychological stress;

• Abuse of thyroid hormones;

• Sheehan syndrome – partial death of cells in the pituitary gland in women after childbirth.

What does a decrease in TSH norm mean?

If the interpretation of test results for the hormone TSH

shows results that are below normal, the patient may assume the following problems and diseases:

• hyperthyroidism in pregnancy;
• thyrotoxic adenoma (also called Plummer's disease);
• diffuse toxic goiter;
• autoimmune thyroiditis with signs of thyrotoxicosis;
• TSH-independent thyrotoxicosis;
• cachexia;
• mental illnesses, disorders.

How to decipher the results of several tests for the hormone TSH

Deviations in the level of concentration of thyroid-stimulating hormone in the patient’s body from the norm in one direction or another directly indicate only malfunctions in the functioning of the thyroid gland. To determine the exact cause of such failures, the doctor, in most cases, together with a TSH test

prescribes tests for the patient for levels T3,
T4.

• Primary hypothyroidism is determined by normal or decreased T3 and T4, increased TSH.
• Secondary hypothyroidism is diagnosed when T3, T4, and TSH levels are reduced.
• Hyperthyroidism is determined by increased T3, T4, decreased TSH.

TPO-AT tests may also be required for accurate diagnosis of hypothyroidism or hyperthyroidism.

, AT-TG, exceeding the norm indicates subacute or autoimmune thyroiditis.