TSH is at the upper limit of normal. Thyroid hormone TSH: norm and deviation from the norm Increased TSH levels

Hormones - what are they? They are the most important substances that take part in the regulation of various processes: metabolism, reproductive activity, and the mental and emotional state of a person. TSH in women is a thyroid-stimulating hormone, the levels of which can indicate changes occurring in the body.

General information about thyroid-stimulating hormone, together with T3 and T4

TTG is one of the most important regulators of work thyroid gland, which, together with the hormones T3 and T4, promotes the formation of new red blood cells, heat exchange and other processes in the body

TTG - what does this abbreviation mean? Thyroid-stimulating hormone, or thyrotropin, is the most important regulator that controls the functioning of the thyroid gland. It is responsible for the production of thyroxine (T4) and triiodothyronine (T3). The latter, in turn, are responsible for the activities reproductive system, metabolic processes of fats, proteins and, correct functioning of the heart muscle and the functioning of blood vessels.

TSH, together with T3 and T4, promotes the production of glucose, participates in heat metabolism, and controls the process of red blood cell production.

A special feature of thyroid-stimulating hormone is that its level fluctuates and is diurnal. Its highest value is recorded at 3 am, and from 9 am to 6 pm this indicator decreases.

Thyrotropin is produced by the pituitary gland, which is located in the brain. The norm of thyroid hormones in women and men has different standards, and in at different ages they differ.

Important! The norm of T3 and T4 in TSH for women depends on their age. If the TSH level deviates from the normal level, this may indicate a disease of the adrenal glands or pituitary gland, which causes the thyroid gland to not work properly. Fluctuations in TSH levels and deviations from the norm are also observed during periods of hormonal instability - during pregnancy, during the lactation period, and also during menopause.

The norm of TSH in women depending on age

The acceptable TSH level in women is an indicator that directly depends on age, hormonal status, and the presence of acquired or congenital pathologies. For 20 years, 40 years, 50 years, the allowable indicator is different. To determine the TSH norm in women by age, a table of acceptable norms for different age ranges and during pregnancy will help:

It should be noted that as the body ages, the function of the thyroid gland decreases, therefore, in women after 50 years of age (more often at the age of 60-70 years), the lower limit of the TSH indicator is 0.4 μIU/ml, the upper limit is 10 μIU/ml.

Fluctuations in TSH levels are associated with different needs for this hormone at different stages of life.

In addition to the TSH level, it is also necessary to take into account T3 and thyroxine (T4) levels. The norm for the first is about 3.5 - 0.8 μIU / ml, free T3 - 2.62-5.69 pmol / l.

The norm for T4 in women is 0.8-1.8 µIU/ml, free T4 is 9-19 pmol/l.

This hormone thyroxine T4 plays an important role in the sexual development of girls. Its level affects the synthesis of sex hormones.

If TSH is low, then the following deviations are observed in girls:

• slowing down the process of puberty;
• delayed onset of menstruation;
• height mammary glands slows down;
• the size of the clitoris and labia are smaller;
• there is no natural interest in sexual activity.

When girls under 8 years of age experience a prolonged increase in TSH, puberty occurs prematurely. This manifests itself in the enlargement of the mammary glands in early age, early onset of menstruation and hair coverage of the armpits and pubis.

Note! In women during pregnancy, the level of thyrotropin hormone differs from the data indicated in the table. In each trimester, its indicators change:

• in the first trimester, the TSH value fluctuates between 0.1-0.4 µIU/ml;
• in the second – 0.2-2.8 µIU/ml;
• in the third – from 0.4 to 3.5 µIU/ml.

During the examination, specialists pay attention to Special attention on changes in the hormones TSH and T4, T3. It is recommended to regularly check their levels during pregnancy, after the age of 40 years (before menopause), and also after 60 years.

The photo shows an example of a table for an immunological study of the thyroid group TSH - T3 total, T3 free, T4 total, T4 free, thyroglobulin, thyroxine-binding globulin, A/T to thyroglobulin, A/T to thyroid peroxidase, A/T to the TSH receptor.

In what cases should you take a TSH test?

If there are problems with the TSH hormone, there are no pronounced symptoms, therefore, if problems are observed in many “points” of the body at once, then a hormone test should be done first.

Knowing what TSH is responsible for, it is necessary to realize the importance of timely hormonal studies for a woman’s health in different years of life and her reproductive capabilities.

Test for blood levels women TSH should be passed if certain deviations are observed:

• psychological and neurological disorders: and, sleep disturbances, irritability, apathy, causeless aggression;
• constant lethargy and weakness;
• decreased libido;
• pain in the throat area;
• active up to baldness;
• inability to get pregnant for a long time;
• – absence of menstruation for several menstrual cycles;
• the temperature often drops below 36 degrees;
• gaining excess weight with lack of appetite;
• increased appetite that is difficult to control;
• constant, persistent headaches;
• the thyroid gland contains seals;
• muscle dysfunction;
• slight trembling throughout the body, especially in the upper extremities.

Adult women also carry out TSH analysis in the following cases:

• if you suspect the presence of autoimmune diseases;
• when planning pregnancy in order to prevent genetic abnormalities in the child;
• during the treatment of certain diseases to monitor the effectiveness of the measures taken;
• if thyroid dysfunction was previously detected as a routine examination.

As a result of the study, a specialist may find that TSH hormone levels are normal, increased or decreased. Deviations affect the female reproductive system and its general condition.

The main reasons for increased thyrotropin levels and treatment approach

If TSH is elevated in women, what does this mean? Elevated TSH in women is the result of a number of pathological disorders in work internal organs. These include:

• tumor processes affecting the pituitary gland;
• adrenal insufficiency;
• damage to the thyroid gland - tumor, trauma, radiation;
• gestosis is a complication of the second half of pregnancy, which is characterized by the appearance of protein in the urine, increased arterial blood levels, and hidden and visible edema.

Other factors that increase the concentration of the thyroid-stimulating hormone TSH include the following:

• lack of iodine in the body;
• excessive physical activity;
• surgical interventions related to the thyroid gland;
• taking certain medications - antipsychotics, antiemetics and anticonvulsants;
• mental disorders;
• surgery performed to remove the gallbladder;
• genetic predisposition.

If the permissible TSH level in women is increased, the following symptoms are observed:

• disruption of the menstrual cycle - scanty discharge accompanied by painful sensations, uterine bleeding, complete absence of menstruation;
• feeling of chilliness, chills;
• heart rate slows to less than 55 beats per minute;
• noticeable weight gain;
• dysfunction digestive system which manifests itself in delayed gastric emptying;
• swelling of the eyelids, lips, limbs;
• muscle weakness.

Note! In the case when a high level of thyrotropin is associated with a pituitary adenoma, specific symptoms are observed - vision decreases, regular pain in the head appears, localized in the temporal region, dark or transparent spots appear in the field of vision.

If thyroid-stimulating hormone is contained in a concentration exceeding 4 µIU/ml, combination therapy is indicated, which includes taking potassium iodide and thyroid hormone.

Also, if TSH is elevated, a diet is prescribed, the observance of which will restore the balance of hormones and saturate the body with substances such as manganese, selenium and cobalt - they help the body absorb iodine. If the norm is too high, a properly organized nutrition system is necessary - this is a guarantee of restoration of metabolic processes.

Factors that reduce TSH levels in a woman’s body

If a woman's TSH is low, this may indicate:

• benign tumor process affecting the thyroid gland;
• damage to the pituitary gland caused by mechanical stress;
• Graves' disease;
• hypothalamic-pituitary insufficiency;
• Plummer's disease.

In addition, TSH can increase due to emotional stress, stressful situations, and calorie deficit.

Under conditions in which the permissible value of the TSH hormone is reduced, the following manifestations are observed:

• sudden, causeless weight loss;
• fragility of bone tissue, which manifests itself in bone pain, frequent fractures, multiple caries;
• rapid heartbeat, accompanied by increased arterial blood pressure;
• feeling of sand in the eyes;
• brittle nails and their slow growth;
• sweating and feeling hot;
• increased appetite;
• rapid mood changes;
• frequent bowel movements;
• attacks of weakness of individual muscles of the body and limbs.

Low TSH requires treatment. Usually, the doctor prescribes medications that contain thyroid-stimulating hormone in different doses. During therapy, it is recommended to exclude foods rich in fats and cholesterol from the diet and increase the amount of vegetables consumed.

How to determine the level of the hormone thyrotropin?

A special test is carried out in compliance with a number of strict rules that allow you to get the most accurate result.

The causes and consequences of a change in the normal level of TSH is an important issue when considering this problem. Violation can lead to such complications as infertility, spontaneous abortion, fetal pathologies acquired during fetal development, premature detachment of the placenta.

To determine whether the level of TSH in women is normal, it is necessary to undergo a special test. Before this diagnostic procedure, you need to familiarize yourself with the rules on how to correctly take an analysis to determine TSH and free T4 levels, as well as T3.

• To obtain a high-quality result, women need to donate blood in the morning, from 8 to 12 o’clock, since the largest amount of the hormone is produced during this period;
• It is advisable to carry out the test on an empty stomach, and two days before it, refuse fatty foods;
• a few days before the procedure, it is recommended to stop drinking alcohol and smoking;
• two days before the test you should not use drugs containing steroid and thyroid hormones;
• Before diagnosis, you should refrain from emotional overstrain.

A test to determine free levels of TSH and T4, as well as T3, will help identify diseases that pose a serious threat to a woman’s full life. It is important to undergo this procedure in a timely manner for pregnant women, as well as for those who have a hereditary predisposition to hormonal disorders. This rule also applies to women over 50 years of age, in whom, as the body ages, all internal processes slow down. An increased or decreased TSH hormone in women in almost all cases indicates abnormalities in the functioning of internal organs.

Knowing what thyroid-stimulating hormone is responsible for in women, it is necessary to realize the importance timely diagnosis its level, identifying pathologies and their treatment. The norm of TSH in women differs by age, which is associated with a change in the need for it throughout life. To determine whether these indicators are normal, only a specialist can use a test for t3 t4 tg normal in women.

A small gland weighing half a gram at the base of the brain is, without exaggeration, a command post endocrine system. The pituitary gland controls the activity of most of the endocrine glands through secreted hormones. Among them is TSH (thyroid-stimulating hormone, thyrotropin, thyrotropin). Thyroid-stimulating hormone regulates the activity of the thyroid gland.

The pituitary gland is the central command post of the endocrine system.

How does the pituitary-thyroid ligament work under normal conditions? TSH stimulates the thyroid gland to produce more thyroid hormones triiodothyrotine (T3) and thyroxine (T4). This important substances, which control the processes of energy formation in the body. When the concentration of T3 and T4 reaches the required level, the pituitary gland reduces the secretion of TSH. If the content of thyroid hormones decreases below a certain threshold, the pituitary gland again increases the secretion of thyrotropin.

Thyrotropin

TSH norm

The level of thyroid-stimulating hormone depends on the age of the person. Other factors also influence its level. Therefore, the norm is determined over a wide range.

1. Most TSH is found in the blood of newborns and infants up to two and a half months (0.6-10 µIU/ml).
2. Then normal thyrotropin levels change. If TSH at the lower limit of normal remains unchanged, then the upper limit decreases. By the age of five, the norm is 0.4-6 µIU/ml.
3. In adolescents, a TSH level of 0.4-5 µIU/ml is considered normal.
4. In adults, thyrotropin is normally 0.4-4 µIU/ml.

However, in some pathologies, an analysis of TSH will show the content of thyroid-stimulating hormone in the blood below normal. What to do in this case and how to treat low TSH? There is no clear answer to this question. And that's why.

Hormones T3 and T4

There is an inverse relationship between TSH and the hormones T3 and T4, therefore, the level of thyrotropin in the blood cannot be considered without linking with the amount of thyroxine and triiodothyronine. There are various situations when a low thyrotropin level is observed. Each has its own symptoms and causes and negatively affects human health.

This is what the thyroid gland looks like in Graves' disease

Situation 1. Thyroid dysfunction

1. A common disease of the thyroid gland, when thyroid-stimulating hormone is reduced, is Basedow's disease.

Characteristic symptoms:

• uniform enlargement of the gland with the formation of a goiter;
• bulging eyes.

Pathological activity of the thyroid gland leads to an increased release of T3 and T4 into the blood. The pituitary gland reacts to their excess by reducing the secretion of thyrotropin. However, the thyroid gland does not perceive this signal.

1. Increased concentrations of T3 and T4 are observed in nodular toxic goiter. With this pathology, nodes (tumor formations) are formed, which leads to increased secretion of T3 and T4. As a result, TSH is lowered.
2. Hashitoxicosis, or autoimmune thyroiditis, destroys the tissues of the gland, which is accompanied by an increased release of hormones into the blood.
3. Another reason is the functional autonomy of the thyroid gland, which is formed with prolonged iodine deficiency.
4. TSH is noted below normal during inflammation of the thyroid gland (acute thyroiditis).
5. Increased activity of the thyroid gland differs in trophoblastic thyrotoxicosis.
6. High levels of thyroid hormones are observed in follicular adenocarcinoma.
7. It is possible to raise T3 and T4 above normal levels due to inadequate treatment of diseases. For example: an overdose of thyroid hormones, excessive use of drugs with a high content of iodine, long-term therapy with interferon.

Situation 2. Pituitary dysfunction

1. Low TSH levels are present not only in thyroid pathologies. This may be due to the functional inability of the pituitary gland to produce the required amount of the hormone.
2. A low rate is observed with tumors of the pituitary gland or hypothalamus.
3. Thyrotropin is lowered when brain tumors put pressure on the pituitary gland.
4. Hypophysitis (an inflammatory autoimmune disease of the pituitary gland).
5. Thyroid-stimulating hormone is reduced when infectious lesions brain.
6. Head injuries, brain surgery in the pituitary region, and radiation can lower the level of TSH.

Situation 3. Other reasons

Low TSH is caused by causes that are not related to the activity of the thyroid gland or pituitary gland. The symptoms of low thyrotropin in these cases differ from the signs that are observed in pathologies of the thyroid gland or pituitary gland.

1. Low levels of thyroid-stimulating hormone with normal T4 result from a stroke or heart attack.
2. Sometimes when normal level B and T3 are the pituitary gland’s response to stress.
3. Even with a normal content of thyroid hormones, a reduced level of thyrotropin is possible during starvation.

Which low TSH is more dangerous for the body?

If you do not take into account extreme cases (cancer, stroke, heart attack), it is worse for the body when TSH is at the lower limit of normal and less than it due to excessive thyroid activity (hyperthyroidism). This means that there is a real threat of thyrotoxicosis (poisoning with hormones T3 and T4).

What are the symptoms of thyrotoxicosis?

1. A person sweats excessively when there are no external factors.
2. Cardiopalmus.
3. Dyspnea.
4. Feeling of heat bursting from within.
5. Weight is lost, although appetite is increased.
6. Suffering nervous system– people become fussy, irritable, and cannot find a place for themselves.

What is the danger of low thyrotropin in combination with thyrotoxicosis?

1. The cardiovascular system suffers.
2. Vegetative-vascular dystonia and myocardial dystrophy may develop. Serious nervous system disorders are possible.

Doctors assess this situation as life-threatening, since an excessive concentration of thyroxine and triiodothyronine destroys tissues and organs.

Depression

With a low level of thyrotropin and a low content of thyroid hormones (hypothyroidism), there is no threat to life, but its quality deteriorates. Hypothyroidism has the following symptoms:

• reduced arterial pressure and weak pulse;
• weight gain with poor appetite;
• swelling;
• lethargy;
• low temperature;
• depressed mood.

Treatment

How to increase TSH if it is less than normal or very low? Treatment for low TSH is prescribed depending on the pathology that caused it. However, regardless of it, the content of the hormones T3 and T4 is adjusted, since they are important for the life of the body.

The deficiency of these substances is compensated by treatment with thyroxine. Then a test for TSH and free T4 is prescribed. Based on its results, the dose of thyroxine is adjusted.

When there is an excess of T3 and T4 in the blood, thyreostatic drugs are prescribed that reduce triiodothyrotine and thyroxine, and thereby increase the level of TSH.

Increase TSH folk remedies It's better not to try. There are many reasons for its low content, so home treatment can be wrong with unpredictable consequences. Hormones require a professional attitude.

Additional information on the topic can be obtained from the video:

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TSH norms during pregnancy, optimal indicators for the birth of a healthy baby?

REFERENCE LIMITS FOR TSH AND THYROID

HORMONES DEPENDING ON AGE AND TERM

PREGNANCY (95% CONFIDENCE INTERVAL)

			T4 free		T3 free
Newborns
Children aged: 6 months
Adults: over 60 years old
Pregnant: 1st trimester 2nd trimester 3rd trimester

NOTE: TSH conversion factor: 1 µIU/ml = 1 IU/l.

Rates may vary when different standard commercial kits are used.

HOW TO PREPARE CORRECTLY FORSTUDY OF THE FUNCTIONAL ACTIVITY OF THE THYROID GLAND IN THE CLINICAL DIAGNOSTIC LABORATORY

1) The study is carried out in the morning on an empty stomach - at least 8 - 12 hours must pass between the last meal and blood drawing. In the evening of the previous day, a light dinner is recommended. It is advisable to exclude fatty, fried foods and alcohol from the diet 1–2 days before the examination. If there was a feast the day before or a visit to the bathhouse or sauna, it is necessary to reschedule the laboratory test for 1-2 days. You must refrain from smoking 1 hour before taking blood.

2) You should not donate blood after X-ray examinations or physiotherapeutic procedures.

3) It is necessary to exclude factors that influence the research results: physical stress (running, climbing stairs), emotional arousal. Before the procedure, you should rest for 10–15 minutes and calm down.

4) It must be remembered that the result of the study may be distorted by the effects of the drugs taken medicines or products of their metabolism. Prescription and discontinuation of any drug is accompanied by changes in laboratory parameters. Therefore, before taking the test, you should consult your doctor about the possibility of limiting your medications to prepare for the test. It is recommended to stop taking medications before donating blood for testing, that is, blood is drawn before taking medications.

5) Taking into account the daily rhythms of changes in blood parameters, it is advisable to carry out repeated studies at the same time.

6) Can be used in different laboratories different methods research and units of measurement. In order for the assessment of the examination results to be correct and the results to be acceptable, it is advisable to conduct research in the same laboratory at the same time.

Test for thyroid hormones. 2 - 3 days before the study, do not take iodine-containing drugs, 1 month - thyroid hormones (to get true basal levels), unless there are special instructions from the endocrinologist. However, if the purpose of the study is to control the dose of thyroid hormone drugs, blood is drawn while taking the usual dose. It should be borne in mind that taking levothyroxine causes a transient, significantly increased level of total and free thyroxine in the blood for approximately 9 hours (by 15–20%).

Thyroglobulin test It is advisable to carry out at least 6 weeks after thyroidectomy or treatment. If such diagnostic procedures, like a biopsy or thyroid scan, then a study of the level of TG in the blood must be strictly carried out before the procedures. Since patients after radical treatment of differentiated thyroid cancer receive high doses of thyroid hormones (to suppress the secretion of TSH), against the background of which the TG level also decreases, its concentration should be determined 2 to 3 weeks after the cessation of suppressive therapy with thyroid hormones.

THYROTROPIC HORMONE (TSH, THYROTROPIN)

TSH is a reference criterion for laboratory assessment of thyroid function. It is with this that diagnosis should begin if deviations in the hormonal activity of the thyroid gland are suspected. TSH is a glycoprotein hormone that is produced in the anterior lobe of the pituitary gland and stimulates the synthesis and iodination of thyroglobulin, the formation and secretion of thyroid hormones. Pituitary secretion of TSH is very sensitive to changes in the concentration of T 3 and T 4 in the blood serum. A decrease or increase in this concentration by 15-20% leads to reciprocal shifts in TSH secretion (feedback principle).

The existence of a dependence of the formation and secretion of TSH on the action of drugs, the daily rhythm of changes in TSH levels, the state of stress and the presence of somatic diseases in the patient should be taken into account when interpreting the results of the study.

The biological half-life of TSH is 15 - 20 minutes.

INDICATIONS FOR TSH DETERMINATION: diagnosis of thyroid function disorders, different kinds hypothyroidism, hyperthyroidism, delayed mental and sexual development in children, cardiac arrhythmias, myopathy, depression, alopecia, infertility, amenorrhea, hyperprolactinemia, impotence and decreased libido.

Monitoring the condition of patients during replacement therapy hormone therapy: TSH secretion is suppressed during standard therapy or during postoperative replacement therapy.

Normal or elevated TSH levels indicate an inadequate dose of the drug, incorrect hormonal therapy, or the presence of antibodies to thyroid antigens. During replacement therapy for hypothyroidism, the optimal TSH level is within the lower reference values. During replacement therapy, blood must be drawn for TSH testing 24 hours after the last dose of the drug.

·screening for congenital hypothyroidism: On the 5th day of the child’s life, the level of TSH in the blood serum or a blood spot on filter paper is determined. If the TSH level is greater than 20 mIU/L, a new blood sample should be retested. When the TSH concentration is in the range from 50 to 100 mIU/L, there is a high probability of the presence of the disease. Concentrations above 100 mIU/L are typical for congenital hypothyroidism.

PHYSIOLOGICAL CONDITIONS LEADING TO CHANGES IN THE LEVEL OF TSH IN THE BLOOD

In healthy newborns, at birth there is a sharp rise in TSH levels in the blood, which decreases to the basal level by the end of the first week of life.

In women, the concentration of TSH in the blood is approximately 20% higher than in men. With age, the concentration of TSH increases slightly, and the amount of hormone emissions at night decreases. Elderly people often experience reduced levels TSH must also be taken into account in these cases low sensitivity to stimulation.

TSH concentration increases during pregnancy (oral contraceptives and the menstrual cycle do not affect the dynamics of the hormone)

TSH is characterized by daily fluctuations in secretion: TSH in the blood reaches its highest values ​​​​at 24 - 4 o'clock in the morning, at morning hours The highest level in the blood is determined at 6–8 hours. Minimum TSH values ​​are determined at 15-18 pm. The normal rhythm of TSH secretion is disrupted when awake at night. TSH levels are not affected by the interval after taking levothyroxine. It is recommended to repeat the analysis if the results obtained do not correspond clinical picture and parameters of other studies.

In middle-aged women and old men, the maximum peak of serum TSH occurs in December.

During menopause, an increase in TSH levels may be observed with an intact thyroid gland.

DISEASES AND CONDITIONS IN WHICH CHANGES IN TSH LEVELS IN THE BLOOD POSSIBLE

INCREASING TSH LEVELS

DECREASED TSH LEVELS

Hemodialysis. Preeclampsia (preeclampsia). Contact with lead. Subacute thyroiditis (recovery phase). After heavy physical activity. Excessive secretion of TSH in pituitary adenomas (thyrotropinoma): thyrotoxicosis of central origin. Stop smoking. The secretion of TSH by pituitary adenomas is not always autonomous, but is subject to partial feedback regulation. When such patients are prescribed thyreostatic drugs (methylthiouracil, Mercazolil and others) and their level of thyroid hormones in the blood decreases under the influence of treatment, a further increase in the TSH content in the blood serum is observed. Primary hypothyroidism. Syndrome of unregulated TSH secretion. Hashimoto's thyroiditis with clinical and subclinical hypothyroidism. Severe somatic and mental illnesses. Exercises on a bicycle ergometer. Cholecystectomy. Ectopic secretion of TSH (lung, breast tumors). TSH secretion is stimulated low temperature and low blood pressure.

Acromegaly. Secondary amenorrhea. Hyperthyroidism in pregnancy and postpartum pituitary necrosis. Pituitary dwarfism. Starvation. Diffuse and nodular toxic goiter. Delayed sexual development. Neurogenic anorexia. General diseases in old age. Psychological stress. Klinefelter's syndrome. Cushing's syndrome. Subclinical thyrotoxicosis. T3 toxicosis. Heat stress. Pituitary gland injury. Transient thyrotoxicosis in autoimmune thyroiditis. TSH-independent thyrotoxicosis. Inhibitory effect of GH on the synthesis and release of TSH. Chronic renal failure. Cirrhosis of the liver. Exogenous therapy with thyroid hormones. Endogenous depression. Endocrine ophthalmopathy.

CLINICAL DIAGNOSTIC VALUE OF TSH

· In treated hyperthyroid patients, TSH may remain low for 4-6 weeks after achieving a euthyroid state.

· In pregnant women and women taking contraceptives, normal TTT levels and elevated T 3 and T 4 levels occur with euthyroidism.

· The absence of primary thyroid disease can be stated in any patient who has normal TSH and T4 in combination with an isolated deviation (in any direction) of T3.

· In severely ill patients with normal concentrations of T4 and T3, TSH production may be impaired.

· TSH secretion is suppressed during treatment with thyroxine and postoperative replacement therapy. Normal or elevated TSH levels in these cases indicate a low dose of the drug, peripheral resistance to thyroid hormones, or the presence of antibodies to thyroid hormones.

· During replacement therapy for hypothyroidism, the optimal TSH level should be below the reference values.

MAIN CRITERIA FOR DIFFERENTIAL DIAGNOSIS OF SUBCLINICAL HYPOTHYROIDSIS

Basic conditions accompanied by an increase in TSH levels

* Secondary and tertiary hypothyroidism is accompanied in 25% of cases slight increase TSH level with decreased biological activity with a significant decrease in T4.

* With thyroid hormone resistance syndrome, a slight increase in TSH levels is detected with an increased content of thyroid hormones in the blood.

* Uncompensated primary adrenal insufficiency is sometimes accompanied by an increase in TSH levels, which is normalized when glucocorticosteroids are prescribed.

* In case of TSH-producing pituitary adenoma, elevated levels of TSH and thyroid hormones are determined.

* Chronic renal failure may be accompanied by an increase in TSH both due to a delay in iodine excretion (true hypothyroidism) and due to the use of drugs that increase the level of TSH in the blood and the accumulation of metabolites.

* During exacerbation mental illness Every fourth patient may have a transient increase in TSH levels associated with activation of the hypothalamic-pituitary-thyroid system.

* Effect of antidopamine drugs (metoclopramide and sulpiride), amiodarone.

* Syndrome of non-thyroid diseases.

MEDICINES THAT AFFECT TSH LEVELS IN THE BLOOD

INFLATING THE RESULT

UNDERSTANDING THE RESULT

AMIODARONE (EUTHYROID AND HYPOTHYROID PATIENTS) BETA BLOCKERS (ATENOLOL, METOPROLOL, PROPRANOLOL) HALOPERIDOL CALCITONIN (MIACALCIK) CLOMIFEN LOVASTATIN (MEVACOR) METHIMIZOL (MERCAZOLIL) NEUROLEPTICS (PHENOTHIAZINES, AMINOGLUTETHIMIDE) PARLODEL (BROMOCRYPTINE) prednisone ANTIEMETICS (MOTILIUM, METOCLOPRAMIDE, DOMPERIDONE) ANTICONVULSATIVE DRUGS (BENSERAZIDE, PHENYTOIN, VALPROIC ACID) X-RAY CONTRAST MEANS RIFAMPICIN IRON SULPHATE (HEMOFER, FERROGRADUM) SULPIRIDE (EGLONYL) FUROSEMIDE (LASIX) FLUNARIZINE CHLORPROMAZINE (AMINAZINE) ERYTHROSINE

AMIODARONE (HYPERTHYROID PATIENTS) ANABOLIC STEROID DOPAMINE RECEPTOR ANTAGONISTS BETA-ADRENOMIMETICS (DOBUTAMINE, DOPEXAMINE) VERAPAMIL (ISOPTIN, FINOPTIN) INTERFERON-2 CARBAMAZEPINE (FINLEPSIN, TEGRETOL) LITHIUM CARBONATE (SEDALITE) CLOFIBRATE (MISCLERONE) CORTISOL (INHIBERS TSH SECRETION) CORTICOSTEROIDS LEVODOPA (DOPAKINE, NACOM, MADOPAR) LEVOTHYROXINE (EUTHYROX) METERGOLINE NIFEDIPINE (ADALAT, CORDIPIN, CORINTHAR) OCTREOTIDE (SANDOSTATIN) PYRIDOXINE (VITAMIN B6) SOMATOSTATIN DRUGS FOR TREATING HYPERPROLACTINEMIA (PERIBEDIL, BROMOCRYPTINE, METERGOLINE) TRIDOTHYRONINE PHENTOLAMINE CIMETIDINE (HISTODIL) CYPROHEPTADINE (PERITOL) CYTOSTATIC

THYROXINE (T 4)

Thyroxine is a thyroid hormone, the biosynthesis of which occurs in the follicular cells of the thyroid gland under the control of TSH. The main fraction of organic iodine in the blood is in the form of T4. About 70% of T4 is associated with thyroxine-binding globulin (TB), 20% with thyroxine-binding prealbumin (TSPA) and 10% with albumin. Only 0.02 - 0.05% of T 4 circulates in the blood in a state not bound to proteins - the free T 4 fraction. The concentration of T4 in serum depends not only on the rate of secretion, but also on changes in the binding capacity of proteins. Free T4 makes up 0.02 - 0.04% of total thyroxine.

Biological half-life T 4 – 6 days.

PHYSIOLOGICAL CONDITIONS LEADING TO CHANGES IN THE LEVEL OF T 4 IN THE BLOOD

In healthy newborns, the concentration of free and total T4 is higher than in adults.

Levels of the hormone in men and women remain relatively constant throughout life, decreasing only after 40 years.

During pregnancy, the concentration of thyroxine increases, reaching maximum values ​​in the 3rd trimester.

During the day, the maximum concentration of thyroxine is determined from 8 to 12 hours, the minimum - from 23 to 3 hours. During the year, the maximum T4 values ​​are observed between September and February, the minimum in the summer.

DISEASES AND CONDITIONS IN WHICH CHANGES IN THE LEVEL OF T 4 IN THE BLOOD ARE POSSIBLE

Hemolysis and repeated thawing and freezing of serum may result in decreased T4 results. High serum bilirubin concentrations contribute to overestimation of results. The presence of the preservative EDTA gives falsely elevated results for free T4. Fasting, poor low protein diet, lead exposure, severe muscle exercises and training, excessive physical effort, various types of stress, weight loss in obese women, surgery, hemodialysis can contribute to a decrease in total and free T4 levels. Hyperemia, obesity, interruption of heroin intake (due to an increase in transport proteins) cause an increase in T4, heroin reduces free T4 in the blood serum. Smoking causes both a decrease and an increase in thyroxine test results. Applying a tourniquet when drawing blood with and without “hand work” causes an increase in total and free T4.

T4 levels in umbilical vein blood are lower in preterm infants compared to term infants and are positively correlated with the birth weight of full-term infants. High T4 values ​​in newborns are caused by increased TSH; free T4 is close to the level in adults. The values ​​increase sharply in the first hours after birth and gradually decrease by 5 years. In men there is a decrease during puberty, but in women this is not observed.

The concentration of free T4, as a rule, remains within the normal range in severe diseases not related to the thyroid gland (the concentration of total T4 may be reduced).

DISEASES AND CONDITIONS IN WHICH CHANGES IN TOTAL T 4 LEVEL ARE POSSIBLE

INCREASING OVERALL T LEVELS 4

REDUCTION OF TOTAL LEVEL 4

HIV infection. Acute hepatitis (4 weeks) and subacute hepatitis. Hyperthyroidism, conditions with increased TSH (pregnancy, genetic increase, acute intermittent porphyria, primary biliary cirrhosis). Hyperestrogenism (increased total T4 content due to an increase in TSH, while the level of free T4 remains normal). Diffuse toxic goiter. Obesity. Acute mental disorders. Acute thyroiditis (isolated cases). Postpartum thyroid dysfunction. Thyroid hormone resistance syndrome. Thyrotropinoma. Toxic adenoma. Thyroiditis. TSH – independent thyrotoxicosis. Choriocarcinoma

Secondary hypothyroidism (Sheehan syndrome, inflammatory processes in the area of ​​the pituitary gland). Hypothyroidism, conditions with a decrease in TSH (nephrotic syndrome, chronic liver diseases, protein loss through the gastrointestinal tract, nutritional disorders, genetic decrease in TSH). Panhypopituitarism. Primary hypothyroidism (congenital and acquired: endemic goiter, AIT, neoplastic processes in the thyroid gland). Tertiary hypothyroidism (traumatic brain injury, inflammatory processes in the hypothalamus).

CLINICAL DIAGNOSTIC VALUE T 4

· an isolated increase in total T4 against the background of normal TSH and T3 values ​​may be a rare finding. This appears to be a patient with normal thyroid function but congenital excess hepatic production of thyroid hormone transport proteins.

· with “isolated” T3 hyperthyroidism, the level of free and total T4 is within normal limits.

· at the initial stage of hypothyroidism, the level of free T3 decreases earlier than total T4. The diagnosis is confirmed in the case of an increase in TSH or an excessive response to TRH stimulation.

· A normal T4 level does not guarantee normal thyroid function. T 4 within the normal range can be with endemic goiter, suppressive or replacement therapy, with a latent form of hyperthyroidism or a latent form of hypothyroidism.

· In case of hypothyroidism, thyroxin contributes to the normalization of TSH and T 4 . Elevated concentrations of total and free T 4 and the concentration of TSH in the region of the lower limit of the norm are observed when selecting adequate replacement therapy.

· during thyreostatic therapy, the level of T 4 in the region of the upper limit of the norm indicates an adequate choice of a maintenance dose.

· An elevated level of free T 4 does not always indicate a violation of the function of the thyroid gland. This may be due to taking certain medications or serious general diseases.

MEDICINES AFFECTING THE LEVEL OF TOTAL T 4 IN THE BLOOD

INFLATING THE RESULT

UNDERSTANDING THE RESULT

AMIODARONE (IN THE BEGINNING OF TREATMENT AND IN LONG-TERM TREATMENT) AMPHETAMINES DEXTRO-THYROXINE DINOPROST TROMETHAIN LEVATERENOL LEVODOPA (DOPAKINE, NACOM, MADOPAR, SINEMET) OPIATES (METHADONE) ORAL CONTRACEPTIVES thyroid hormone preparations propylthiouracil PROPRANOLOL (ANAPRILINE) PROSTAGLANDIN X-RAY CONTRAST IODINE PREPARATIONS (IOPANOIC ACID, IPODATE, TYROPANOIC ACID) TAMOXIFEN Thyroid hormone THYROTROPIN PHENOTHIAZINE FLUOROURACIL (FLUOROPHENAZINE) CHOLECYSTOGRAPHIC V-VA SYNTHETIC ESTROGENS (MESTRANOL, STILBESTROL) ETHER (IN DEEP NARCOSIS)

AMINOGLUTEMIDE (DRUGS FOR TREATING BREAST CANCER) AMIODARONE (CORDARONE) ANDROGENS (STANOZOLOL, NANDRONOLOL), TESTOSTERONONE ANTICONVULSANTS (VALPROIC ACID, PHENYTOIN, PHENOBARBITAL, CARBAMAZEPINE) ASPARAGINASE ATENOLOL BARBITURATES HYPOLYPIDEMIC DRUGS (LOVASTATIN, CLOFIBRATE, CHOLESTYRAMINE) DIAZEPAM (VALIUM, RELANIUM, SIBAZON) ISOTRETHIONINE (ROACCUTENE) CORTISOL CORTICOSTEROIDS (CORTISONE, DEXAMETHASONE) CORTICOPROPIN METAMIZOL (ANALGIN) NSAIDs (DICLOFENAC, PHENYLBUTAZONE) OXYPHENBUTAZONE (THANDERYL) PENICILLIN SULPHONYLUREAS (GLIBENKLAMIDE, DIABETON, TOLBUTAMIDE, CHLORPROPAMIDE) ANTIFUNGAL DRUGS (INTRACONAZOLE, KETOCONAZOLE) ANTI-TUBERCULOSIS DRUGS (AMINOSALICYLIC ACID, ETHIONAMIDE) RESERPINE RIFAMPIN SOMATOTROPIN SULPHANAMIDES (CO-TRIMOXAZOLE) TRIDOTHYRONINE FUROSEMIDE (TAKEN IN LARGE DOSES) CYTOSTATICS

MEDICINES AFFECTING FREE T 4 LEVEL

INFLATING THE RESULT	UNDERSTANDING THE RESULT
AMIODARONE VALPROIC ACID DIFLUNISAL IOPANOIC ACID LEVOTHYROXINE MECLOPHENAMIC ACID PROPYLTHIOURACIL PROPRANOLOL RADIOGRAPHIC DRUGS	ANTICONVULSANTS (PHENYTOIN, CARBAMAZEPINE) – FOR LONG-TERM TREATMENT AND PREGNANT WOMEN WITH EPILEPSY METHADONE RIFAMPIN HEPARIN HEROIN ANABOLIC STEROID CLOFIBRATE LITYA PREPARATIONS OCTREOTIDE ORAL CONTRACEPTIVES OVERDOSE OF THYROOSTATICS

DISEASES AND CONDITIONS IN WHICH CHANGES IN FREE T 4 LEVEL ARE POSSIBLE

INCREASING THE LEVEL OF FREE T 4

REDUCTION OF FREE T2 LEVEL 4

Hyperthyroidism. Hypothyroidism treated with thyroxine. Diseases associated with increased free fatty acids. Postpartum thyroid dysfunction. Thyroid hormone resistance syndrome. Conditions in which the level or binding capacity of TSH is reduced. Thyroiditis. Thyrotoxic adenoma. Toxic goiter. TSH-independent thyrotoxicosis.

Secondary hypothyroidism (Sheehan syndrome, inflammatory diseases in the area of ​​the pituitary gland, thyrotropinoma). Low protein diet and significant iodine deficiency. Fluctuations in free T4 levels may occur in euthyroid patients with acute or chronic nonthyroidal illnesses Contact with lead. Primary hypothyroidism not treated with thyroxine (congenital and acquired: endemic goiter, AIT, neoplasms in the thyroid gland, extensive resection of the thyroid gland). Late pregnancy. A sharp decrease in body weight in obese women. Tertiary hypothyroidism (TBI, inflammatory processes in the hypothalamus). Surgical interventions.

TRIDOTHYRONINE (T 3)

Triiodothyronine is a thyroid hormone that is 58% iodine. Part of the serum T 3 is formed by enzymatic deiodination of T 4 in peripheral tissues, and only a small amount is formed by direct synthesis in the thyroid gland. Less than 0.5% of T 3 circulating in serum is in free form and biologically active. The remaining T 3 is in a reversible relationship with serum proteins: TSH, TSPA and albumin. The affinity of T 3 to whey proteins is 10 times lower than T 4 . In this regard, the level of free T 3 does not have such a great diagnostic value as the level of free T 4 . At least 80% of circulating T3 is derived from T4 monodeiodization in peripheral tissues. T 3 is 4–5 times more active in biological systems than T 4 . Although the minimum serum concentrations of T 3 100 times lower than the concentration of T 4 , most immunoassays have little cross-reactivity with T 4 . Because T3 levels change rapidly under the influence of stress or other non-thyroid factors, T3 measurement is not the best general test for determining thyroid status. Free T3 makes up about 0.2 - 0.5% of total T3.

The biological half-life of T 3 is 24 hours.

INDICATIONS FOR DETERMINING T 3

· differential diagnosis of thyroid diseases,

· control study for isolated T 3 toxicosis,

· initial stage hyperfunction of the thyroid gland, in particular of autonomous cells,

acute hyperthyroidism after suppressive therapy with thyroxine,

relapse of hyperthyroidism.

To exclude an overdose of drugs, it is necessary to control the level of T 3, which should be within the normal range.

PHYSIOLOGICAL CONDITIONS LEADING TO CHANGES IN THE LEVEL OF T 3 IN THE BLOOD

The concentration of T 3 in the blood serum of newborns is 1/3 of its level observed in adults, but already within 1-2 days it increases to the concentration detected in adults. In the early childhood the concentration of T 3 decreases somewhat, and in adolescence (by 11-15 years) again reaches the level of an adult. After 65 years, there is a more significant decrease in the level of T 3 compared with T 4 . Women have lower concentrations of T 3 than men, on average by 5-10%.

During pregnancy (especially in the 3rd trimester), the concentration of T 3 in the blood increases by 1.5 times. After childbirth, the hormone level returns to normal within 1 week.

T 3 indicators are characterized by seasonal fluctuations: the maximum level occurs in the period from September to February, the minimum in the summer period.

DISEASES AND CONDITIONS IN WHICH CHANGES IN THE LEVEL OF T 3 IN THE BLOOD ARE POSSIBLE

INCREASED RESULTS	REDUCED RESULTS
High altitude above sea level. Heroin mania. Increase in body weight. Stopping heroin use. With iodine deficiency, a compensatory increase in the levels of total and free T3 occurs. When applying a tourniquet to draw blood for 3 minutes. without “hand work” it is possible to increase T 3 by about 10%. Physical exercise.	Hemodialysis. Hyperthermia. Starvation. Premature newborns. Low calorie diet. Acute diseases. Plasmapheresis. Poor diet low in protein. After abortions. Weight loss. Severe somatic diseases. Heavy physical activity in women. Electroconvulsive therapy.

DISEASES AND CONDITIONS UNDER WHICH CHANGES IN TOTAL T3 ARE POSSIBLE

INCREASED RESULTS

REDUCED RESULTS

Hyperthyroidism. Iodine deficiency goiter. Treated hyperthyroidism. Initial nonthyroidal failure. Conditions with increased TSH. T 3 - thyrotoxicosis.

Hypothyroidism (with early or mild primary hypothyroidism, T 4 decreases more than T 3 - a high T 3 / T 4 ratio). Uncompensated primary adrenal insufficiency. Acute and subacute non-thyroid diseases. Primary, secondary and tertiary hypothyroidism. The period of recovery after serious illness. Syndrome of the euthyroid patient. Conditions with low TSH. Severe non-thyroid pathology, including somatic and mental illness. chronic diseases liver.

MEDICINES AFFECTING TOTAL T 3

INFLATING THE RESULT	UNDERSTANDING THE RESULT
AMIODARONE (CORDARONE) ANDROGENS ASPARAGINASE DEXTROTHYROXINE DINOPROST TROMETAIN (ENZAPROST) ISOTRETHIONINE (ROACCUTENE) METHADONE (DOLOFIN, FISEPTON) ORAL CONTRACEPTIVES PROPYLTHIOURACIL PROPRANOLOL (ANAPRILINE) ANTICONVULTS SALICYLATES TERBUTALINE CHOLECYSTOGRAPHIC B – VA CIMETIDINE (HISTODIL) ESTROGENS	DEXAMETHASONE (SERUM CONCENTRATIONS MAY DECREASE BY 20 - 40%)

DISEASES AND CONDITIONS IN WHICH CHANGES IN FREE T3 are POSSIBLE

MEDICINES AFFECTING FREE T 3 LEVEL

INFLATING THE RESULT	UNDERSTANDING THE RESULT
DEXTROTHYROXINE FENOPROPHEN (NALFON)	AMIODARONE (CORDARONE) VALPROIC ACID (CONVULEX, ENCORATE, DEPAKINE) NEOMYCIN (COLYMYCIN) PRAZOSIN PROBUCOL PROPRANOLOL (ANAPRILIN, OBZIDAN) THYROXINE PHENYTOIN (DYPHENINE) CHOLECYSTOGRAPHIC DRUGS (IOPANOIC ACID, IPODAT)

CLINICAL DIAGNOSTIC VALUE T 3

· With iodine deficiency, a compensatory increase in total and free T 3 is observed. Thus, the body adapts to the lack of “raw materials”. Providing a sufficient amount of iodine entails normalization of T3. These individuals do not require any treatment. Misinterpretation of an elevated level of T 3 as T 3 -toxicosis, despite normal TSH and sometimes even reduced T 4 , can lead to unreasonable prescription of thyreostatics, which is a gross mistake.

· with hypothyroidism, the levels of total and free T 3 can be in the region of the lower limit of the norm for a long time, since the increased peripheral conversion of T 4 to T 3 compensates for the decrease in T 3 .

The normal level of T 3 can be with hidden functional defects of the thyroid function, with hypothyroidism, compensated for the conversion of T 4 to T 3 .

· During goiter treatment or postoperative thyroxine replacement, TSH and T3 levels are measured to prevent dosing.

· in the treatment of hypothyroidism with thyroxine, the increase in T3 is much less compared to T4. When administering large doses thyroxine TSH suppressed to non-recordable values. To exclude an overdose of drugs, an analysis of the level of T 3 is carried out, which should be within the normal range.

· at the beginning of the course of thyreostatic therapy, the level of T 3 may increase as a result of compensation processes.

· determination of the level of T 3 in serum has low sensitivity and specificity in hypothyroidism, since the activation of the conversion of T 4 to T 3 maintains the level of T 3 within the normal range until the development of severe hypothyroidism. Patients with NTZ or in a state of energy hunger have low T 3 and o T 3 values. T3 should be measured in conjunction with free T4 in the diagnosis of complex and unusual manifestations of hyperthyroidism or some rare conditions. High T 3 levels are common and early sign relapse of Graves' disease. A high or normal level of T 3 occurs in hyperthyroidism in patients with NTZ against the background of a decrease in the content of TSH (less than 0.01 mIU / l). A high or normal T3 level occurs in cordarone-induced hyperthyroidism.

ALGORITHM FOR LABORATORY ASSESSMENT OF FUNCTION

THYROID GLAND

TSH is elevated free T4 is increased or normal, free T3 is decreased or normal.	* Acceptance of amiodarone, iodine-containing radiopaque agents, large doses of propranolol. * Severe non-thyroid pathology, including somatic and mental illness. * Uncompensated primary adrenal insufficiency. * Recovery period.
TSH is elevated free T4 is increased or normal, clinical euthyroidism.	* Total resistance to thyroid hormones.
TSH is elevated free T4 is normal	* Recent correction with thyroid hormones. * Insufficient therapy with thyroid hormones, patients do not complain.
TSH is low, free T 4 increased, free T 3 reduced.	* Artificial thyrotoxicosis due to self-prescription of T4.
TSH is low, Free T4 is normal.	* Excessive therapy with thyroid hormones. * Taking medications containing T3.
TSH is normal free T 4 and T 3 are reduced.	* Taking large doses of salicylates.
TSH is elevated free T 4 increased, clinical thyrotoxicosis.	* TSH – secreting tumors.
TSH is normal increase in the level of total T 4 with normal level St. T 4.	* Familial disalbuminemic hyperthyroxinemia.
TSH is elevated free and total T4 are reduced, total and free T 3 are reduced.	* Chronic liver diseases: chronic hepatitis, liver cirrhosis.
Abnormal concentrations of total T 4 and total T 3	* Most often result from binding protein abnormalities rather than from thyroid dysfunction. When the level of TSG changes, the calculated indicators of free T 4 are more reliable than the content of total T 4 . If there is a discrepancy in the levels of free hormones, total T4 and total T3 should be determined.

SOURCES AND MECHANISMS OF ACTION OF ORGANIC

COUNTERTHYROID DRUGS

chemical name	Sources	Mechanism of action
Thiocyanates and isothiocyanates	Cruciferous plants, smoking	Inhibition of iodine-concentrating mechanisms
	Yellow turnip	Interfering with the organization of iodide and the formation of active thyroid hormones in the thyroid gland (the activity of goitrin is 133% of the activity of propylthiouracil).
Cyanogenic glycosides	Cassava, maize, sweet potatoes, bamboo shoots	Converted into isothiocyanates in the body
disulfides	Onion garlic	Thiourea-like antithyroid action
Flavonoids	Millet, sorghum, beans, groundnuts	Inhibition of TPO and iodothyronine deiodinases - inhibition of the peripheral metabolism of thyroid hormones.
Phenols (resorcinol)	Drinking water, coal dust, cigarette smoke	Inhibition of iodine organization in the thyroid gland and inhibition of TPO
Polycyclic aromatic hydrocarbons	Food products, drinking water, groundwater	Acceleration of T4 metabolism due to the activation of hepatic UDP-glucuronyl transferase and the formation of T4 glucuronide
Phthalic acid esters	Plastic products, some types of fish	Inhibition of TPO and iodine incorporation into thyroid hormones
Polychlorinated and polybrominated biphenyls	Freshwater fish	Development of AIT
	Drinking water, food	Hyperplasia of the follicular epithelium, acceleration of thyroid hormone metabolism, increased activity of microsomal enzymes
High levels or deficiency of lithium, selenium		They can block proteolysis of the colloid and the release of TG from the follicles, the entry of iodine into the thyroid gland, the connection of thyroid hormones with serum proteins, and accelerate the process of their deiodination.

TYPES OF NON-THYROID DISEASE SYNDROME,

THEIR IMPORTANCE AND DEVELOPMENT MECHANISMS

Variants of non-thyroid disease syndrome (NTDS)

Low T 3

A decrease in T 3 levels is observed in 70% of hospital patients with systemic diseases with normal thyroid function. Total T 3 is 60% below normal, free T 3 is 40%. The T 4 level is normal. The SNTZ variant is associated with a violation of the conversion of T 4 to T 3 due to a decrease in the activity of 5-monodeiodinase. This condition is also characteristic of starvation and is an adaptive reaction of the body associated with a decrease in basal metabolism.

Low level T 3 and T 4

A simultaneous decrease in the level of T 3 and T 4 is often found in patients in intensive care units. At the same time, a low level of total T4 is an unfavorable prognostic sign. This variant of SNTZ is associated with the presence of an inhibitor of thyroid hormone binding in the blood and an increase in the metabolic clearance of T 4 .

High level T 4

An increase in the level of serum T 4 and reverse T 3 is observed in acute porphyria, chronic hepatitis, primary biliary cirrhosis. At the same time, the level of total T 3 and free T 4 is within the normal range, the level of free T 3 is at the lower limit of the norm or reduced.

DRUG INTERACTIONS AFFECTING

ON THE EFFECTIVENESS OF THYROXINE THERAPY

INTERACTION MECHANISM		DRUG SUBSTANCE
Concomitant use may require an increase in the dose of L-thyroxine
Medicines, blocking receptors, both true catecholamines and pseudomediators formed from thyroxin.	Propranolol (anaprilin, obzidan)
Medicines that reduce the absorption of L-thyroxine.	Cholestyramine (Questran) Aluminum hydroxide Ferrous sulfate (hemofer) Sucralfate (Venter) Colestipol Calcium carbonate
Medicines that accelerate the metabolism of L-thyroxine in the liver	Phenobarbital Phenytoin (diphenin) Carbamazepine (finlepsin) Rifampicin
Concomitant use may require a reduction in the dose of L-thyroxine
Drugs that reduce the level of thyroxine-binding globulin in the blood serum	Androgens Anabolic steroid Glucocorticosteroids

CLINICAL SITUATIONS CHANGING

NEED FOR THYROXINE

INCREASED NEED FOR THYROXINE

* Decreased absorption of T 4 in the intestines: mucosal diseases small intestine(sprue, etc.), diarrhea due to diabetes, cirrhosis of the liver, after jejunojejunal bypass surgery or resection of the small intestine, pregnancy. * Drugs that increase the excretion of unmetabolized T4: rifampicin, carbamazepine, phenytoin. * Taking drugs that reduce the absorption of thyroxine: cholestyramine, aluminum hydroxide, ferrous sulfate, calcium carbonate, sucralfate, colestipol. * Drugs that block the conversion of T 4 to T 3: amiodarone (cordarone), selenium deficiency.

REDUCING THE NEED FOR THYROXINE

* Aging (age over 65 years). * Obesity.

MEDICINES AFFECTING

FUNCTION OF THE THYROID GLAND

MEDICINE	EFFECT ON THE THYROID GLAND
	Induction of hypothyroidism due to inhibition of the synthesis and secretion of thyroid hormones - a decrease in T4 levels and an increase in TSH levels. Reduced rate of formation of T 3 from T 4. (Sometimes drugs containing iodine can cause the “iodine-Basedow” phenomenon)
Lithium preparations	Suppress the secretion of T 4 and T 3 and reduce the conversion of T 4 to T 3, suppress the proteolysis of thyroglobulin.
Sulfonamides (including drugs used to treat diabetes)	They have a weak suppressive effect on the thyroid gland, inhibit the synthesis and secretion of thyroid hormones (have structural and functional disorders thyroid gland).
	Suppresses TSH secretion.
Testosterone, methyltestosterone, nandrolone	Reducing serum TSH and total T4 concentrations and stimulating TSH synthesis.
Phenytoin, Phenobarbital, Carbamazepine	They enhance the catabolism of T4 by enzyme systems of the liver (with long-term use, control of thyroid function is required). With long-term treatment with phenytoin, free T4 and TSH levels may be similar to those in secondary hypothyroidism.
Oral contraceptives	Can cause a significant increase in total T4, but not free T4.
Salicylates	Block iodine uptake by the thyroid gland, increase free T 4 due to decreased binding of T 4 to TSH.
Butadion	Affects the synthesis of thyroid hormones, reducing the level of total and free T4.
Glucocorticoids (with short-term use in large doses and during long-term therapy in medium doses)	They reduce the conversion of T4 to T3 by increasing the concentration of inactive reverse T3, inhibit the secretion of thyroid hormones and TSH and reduce its release into TRH.
Beta blockers	They slow down the conversion of T4 to T3 and lower the level of T3.
Furosemide (in large doses)	Causes a drop in total and free T4 with a subsequent increase in TSH.
	Suppresses T4 uptake by cells. During heparin therapy, an inappropriately high level of free T4 may be detected.

Amiodarone

The effects are multidirectional, depending on the initial supply of iodine and the condition of the thyroid gland. * Amiodarone-induced hypothyroidism most often observed in iodine-sufficient regions. Pathogenesis: Amiodarone, by inhibiting TSH-dependent cAMP production, reduces the synthesis of thyroid hormones and iodine metabolism; inhibits 5-deiodinase, a selenoprotein that ensures the conversion of T4 into T3 and reversion T3, which leads to a decrease in extra- and intrathyroidal T3 content. * Amiodarone-induced thyrotoxicosis most common in iodine-deficient or moderate iodine-deficient areas. Pathogenesis: iodine released from amiodarone leads to an increase in the synthesis of thyroid hormones in existing autonomy zones in the thyroid gland. It is also possible to develop destructive processes in the thyroid gland, the cause of which was the action of amiodarone itself.

PATIENTS TAKEN AMIODARONE (CORDARONE)

Before treatment, a study of basal TSH and anti-TPO levels is necessary. The content of free T 4 and free T 3 is checked if the TSH level is changed. An increase in the level of anti-TPO is a risk factor for thyroid dysfunction during cordarone therapy.

During the first 6 months after the start of therapy, TSH levels may not match the level of peripheral thyroid hormones (high TSH / high free T 4 / low free T 3). If euthyroidism persists, the TSH level usually normalizes over time.

Long-term observation. TSH levels during cordarone therapy should be determined every 6 months. It is the level of TSH in such conditions that is a reliable indicator of thyroid status.

Taking amiodarone initially causes changes in TSH levels towards an increase. This is followed by the dynamics of the levels of reverse T 3, T 4 and T 3. A progressive decrease in the level of T 3 reflects a violation of the peripheral conversion of T 4 to T 3. An increase in the content of total and free T 4 may be associated with the stimulating effect of TSH and / or with a decrease in clearance T 4 .

PATIENTS WITH NON-THYROID

DISEASES (NTD)

Acute and chronic NTZ have complex effects on thyroid test results. Testing should be deferred until recovery, if possible, unless there is a history of concern or symptoms of thyroid dysfunction. In seriously ill patients, as well as in intensive drug treatment Some thyroid test results are difficult to interpret.

The combined determination of TSH and T4 levels makes it possible to most reliably differentiate between true primary thyroid pathology (coincidence of changes in T4 and TSH levels) and transient changes caused by NTZ themselves (divergence in changes in T4 and TSH levels).

The pathological level of free T4 in patients with severe somatic diseases does not prove the presence of thyroid pathology. In the case of a pathological level of free T4, it is necessary to examine the content of total T4. If both indicators (free T4 and total T4) are unidirectionally outside the normal range, thyroid pathology is possible. If the indicators of free T4 and total T4 diverge, then this is most likely due not to thyroid dysfunction, but to a somatic disease or medication use. When identifying a pathological level of total T4, it is necessary to correlate this result with the severity of the somatic disease. A low level of total T4 is typical only for severely ill and dying patients. A low total T4 level in patients outside the intensive care unit suggests hypothyroidism. Elevated levels of total T 3 and free T 3 are reliable indicators of hyperthyroidism in somatic diseases, but normal or low levels of T 3 do not exclude hyperthyroidism.

Determination of TSH levels in patients with NTD. Determination of the level of TSH and T4 (free T4 and total T4) is the most effective combination for identifying thyroid dysfunction in patients with somatic pathology. In such cases, the TSH reference intervals should be expanded to 0.05-10.0 mIU/l. TSH levels may transiently decrease to subnormal values ​​during the acute phase of the disease and increase during the recovery phase.

DIAGNOSIS OF THYROID DISEASES

GLANDS DURING PREGNANCY

A change in the functioning of the thyroid gland in women occurs from the first weeks of pregnancy. It is influenced by many factors, most of which directly or indirectly stimulate the thyroid gland of a woman. This mainly occurs in the first half of pregnancy.

Thyroid-stimulating hormone. Literally from the first weeks of pregnancy, under the influence of chorionic gonadotropin (CG), which has structural homology with TSH, the production of thyroid hormones of the thyroid gland is stimulated. In this regard, the production of TSH is suppressed by the feedback mechanism, the level of which during the first half of pregnancy is reduced in about 20% of pregnant women. With multiple pregnancies, when the level of hCG reaches very high values, the level of TSH in the first half of pregnancy is significantly reduced, and sometimes suppressed, in almost all women. The lowest levels of TSH on average occur at 10-12 weeks of pregnancy. However, in some cases, it may remain somewhat reduced until late in pregnancy.

Thyroid hormones. Determining the level of total thyroid hormones during pregnancy is not informative, since it will always be elevated (in general, the production of thyroid hormones during pregnancy normally increases by 30-50%). The level of free T4 in the first trimester of pregnancy is usually highly normal, but in approximately 10% of those with suppressed TSH levels it exceeds upper limit norms. As pregnancy progresses, the level of free T4 will gradually decrease and by the end of pregnancy it very often turns out to be low-normal. In some patients, even without thyroid pathology and receiving individual iodine prophylaxis, in late pregnancy a borderline decrease in the level of free T4 in combination with a normal TSH level may be detected. The level of free T3, as a rule, changes in the same direction as the level of free T4, but it is less likely to be elevated.

General principles for diagnosing thyroid diseases during pregnancy.

* A combined determination of TSH and free T4 is required.

* Determining the level of total T 4 and T 3 during pregnancy is not very informative.

* TSH levels in the first half of pregnancy are normally low in 20-30% of women.

* Levels of total T 4 and T 3 are normally always elevated (about 1.5 times).

* Free T4 levels are slightly elevated in the first trimester in approximately 2% of pregnant women and in 10% of women with suppressed TSH.

* In late pregnancy, a low-normal or even borderline reduced level of free T4 is often detected with a normal TSH level.

THYROGLOBULIN (TG)

Thyroglobulin is a glycoprotein containing iodine. TG is the main component of the colloid of thyroid gland follicles and performs the function of accumulation of thyroid hormones. Synthesis of thyroid hormones occurs on the surface of TG. TG secretion is controlled by TSH.

The biological half-life of TG in blood plasma is 4 days.

DISEASES AND CONDITIONS IN WHICH CHANGES IN THE TG LEVELS IN THE BLOOD POSSIBLE

An increase in the content of triglycerides in the blood reflects a violation of the integrity of the hematofollicular barrier and is observed in diseases that occur with a violation of the structure of the gland or accompanied by iodine deficiency. The release of TG into the bloodstream increases with stimulation and structural lesions of the thyroid gland. The determination of TG does not make sense in the next 2-3 weeks after the puncture biopsy, since the level of TG can be increased due to the passive release of the colloid into the blood when the gland is traumatized. The level of TG increases in the immediate period after thyroid surgery. The consumption of a large amount of iodine with food suppresses the release of thyroid hormones from the thyroid gland, shifting the balance between the formation and decay of TH in the direction of its formation and accumulation in the colloid. The level of TG can be increased in case of thyroid disease, subacute thyroiditis, enlargement of the thyroid gland under the influence of TSH, and in some cases of benign thyroid adenoma.

The presence of antibodies to TG can cause false-negative results, therefore, in parallel with TG, it is advisable to determine antibodies to TG.

In patients with undifferentiated thyroid cancer, the concentration of TG in the blood rarely increases. In differentiated tumors with low functional activity, the TG level increases to a lesser extent than in tumors with high functional activity. An increase in TG levels has been established in highly differentiated thyroid cancer. Determining the level of TG is of great diagnostic importance for identifying metastases of thyroid carcinoma and dynamic monitoring of the condition of patients during treatment of follicular carcinoma. It has also been established that thyroid cancer metastases have the ability to synthesize TG.

Decrease after surgery surgery or radiation therapy TG level in the blood excludes the presence of metastases. On the contrary, an increase in TG levels may be a sign of a generalized process.

Since patients after radical treatment of differentiated thyroid cancer receive high doses of thyroid hormones (to suppress the secretion of TSH), against the background of which the TG level also decreases, its concentration should be determined 2 to 3 weeks after the cessation of suppressive therapy with thyroid hormones.

In pediatric endocrinology, the determination of TG is of great importance in the management of children with congenital hypothyroidism for selecting the dose of hormone replacement therapy. In case of thyroid aplasia, when TG is not detected in the blood, the maximum dosage is indicated, while in other cases, detection and increase in TG concentration suggests a reversible course of the disease, and therefore the dosage of the hormone can be reduced.

PHYSIOLOGICAL CONDITIONS LEADING TO CHANGES IN THE LEVEL OF TG IN THE BLOOD

TG values ​​in newborns are elevated and decrease significantly during the first 2 years of life.

INDICATIONS FOR DETERMINING TG

Thyroid carcinoma (except medullary cancer),

Early detection of relapses and metastases of well-differentiated thyroid cancer in operated patients,

Evaluation of the effectiveness of radioiodine therapy for metastases of thyroid cancer (based on the decrease in its content in the blood to normal values),

Metastases in the lungs of unknown origin,

Bone metastases of unknown origin, pathological bone fragility,

Determination of TG cannot be carried out for the purpose of differential diagnosis of benign and malignant thyroid tumors.

TG CONCENTRATION IN HEALTHY INDIVIDUALS AND IN VARIOUS THYROD DISEASES

Healthy faces 1.5 – 50ng/ml

Thyroid cancer:

Before surgery 125.9 + 8.5 ng/ml

After surgery without metastases and relapses 6.9 + 1.8 ng/ml

Metastases and relapses of well-differentiated 609.3 + 46.7 ng/ml

thyroid cancer in operated patients

Benign tumors (before surgery) 35.2 + 16.9 ng/ml

Thyrotoxicosis (severe form) 329.2 + 72.5 ng/ml

ANTIBODIES TO THYROGLOBULIN (ANTI-TG)

The thyroid gland, which contains specific antigens, can lead the body’s immune system to a state of auto-aggression. One of these antigens is thyroglobulin. Damage to the thyroid gland in autoimmune or neoplastic diseases can cause TG to enter the bloodstream, which, in turn, leads to activation of the immune response and the synthesis of specific antibodies. The concentration of anti-TG varies over a wide range and depends on the disease. Therefore, determining the concentration of anti-TG can be used for diagnosis and monitoring of treatment of thyroid diseases.

DISEASES AND CONDITIONS IN WHICH CHANGES IN THE LEVELS OF ANTI-TG IN THE BLOOD POSSIBLE

Anti-TG is an important parameter for identifying autoimmune thyroid diseases and is carefully measured during disease monitoring. An increase in the level of anti-TG is determined in Hashimoto's thyroiditis (more than 85% of cases), Graves' disease (more than 30% of cases), thyroid cancer (45% of cases), idiopathic myxedema (more than 95% of cases), pernicious anemia (50% of cases, low titers), SLE (about 20% of cases), subacute de Quervain's thyroiditis (low titers), hypothyroidism (about 40% of cases), DTG (about 25% of cases), a weakly positive result can be obtained with non-toxic goiter.

Estrogen-progesterone therapy for contraception increases the titer of antibodies to thyroglobulin and peroxidase. In women with AIT, when taking these drugs, the antibody titer is significantly higher than in people with AIT who do not take these drugs.

An increased titer of anti-TG can be obtained in patients with non-endocrine diseases when taking drugs that affect the nature of the immune response.

In patients with Hashimoto's thyroiditis, the anti-TG titer usually decreases during treatment, but there may be patients in whom anti-TG may persist or be detected in waves over a period of about 2 to 3 years. The anti-TG titer in pregnant women with Graves' disease or Hashimoto's disease decreases progressively during pregnancy and increases transiently after delivery, reaching a peak after 3 to 4 months. A normal anti-TG titer does not exclude Hashimoto's thyroiditis. The microsomal antibody test is more sensitive for Hashimoto's thyroiditis than the anti-TG test, especially in patients younger than 20 years of age.

Determination of anti-TG makes it possible to predict thyroid dysfunction in patients with other autoimmune endocrine diseases and in family members with hereditary organ-specific autoimmune diseases. Weak positive results usually found in other autoimmune disorders and chromosomal disorders such as Turner syndrome and Down syndrome.

Positive results in some patients with hyperthyroidism suggest a combination with thyroiditis. The use of anti-TG to detect autoimmune thyroid diseases is especially justified in iodine-deficient areas.

Children born to mothers with high titers of anti-TG may develop autoimmune thyroid diseases throughout their lives, which requires that such children be classified as a risk group.

About 5 - 10% practically healthy people may have a low titer of anti-TG without symptoms of the disease, more often in women and older people, which is probably due to the identification of individuals with subclinical forms of autoimmune thyroiditis.

INDICATIONS FOR ANTI-TG DETERMINATION: - newborns: high titer of anti-TG in mothers, - Hashimoto's chronic thyroiditis, - differential diagnosis of hypothyroidism, - diffuse toxic goiter (Graves' disease), - postoperative management of patients with well-differentiated thyroid cancer in combination with TG, - assessment of anti-TG levels in iodine-deficient areas in serum contributes to the diagnosis of autoimmune thyroid pathology in patients with nodular goiter.

REFERENCE LIMITS – 0 – 100 IU/ml

ANTIBODIES TO THYROID PEROXIDASE

(ANTI – TPO)

The anti-TPO test is used to verify autoimmune thyropathies. Having the ability to bind to complement, anti-TPO are directly involved in auto-aggression, that is, they are an indicator of aggression immune system in relation to one's own body. Thyroid peroxidase provides the formation of an active form of iodine, which can be involved in the process of iodification of thyroglobulin, that is, it plays a key role in the process of synthesis of thyroid hormones. Antibodies to the enzyme block its activity, as a result of which the secretion of thyroid hormones, mainly thyroxine, decreases. Anti-TPO is the most sensitive test for detecting autoimmune thyroid diseases. Usually their appearance is the first shift that is observed during the development of hypothyroidism due to Hashimoto's thyroiditis.

DISEASES AND CONDITIONS IN WHICH CHANGES IN ANTI-TPO LEVEL ARE POSSIBLE

Autoimmune thyroid diseases are the main factor underlying hypothyroidism and hyperthyroidism and develop in genetically predisposed individuals. Thus, measurement of circulating anti-TPO is a marker of genetic susceptibility. The presence of anti-TPO and elevated TSH levels predict the development of hypothyroidism in the future.

High concentrations of anti-TPO are observed in Hashimoto's thyroiditis (sensitivity 90–100%) and Graves' disease (sensitivity 85%). The level of anti-TPO increases by 40–60% in DTG, but to a lesser extent than in the active stage of Hashimoto’s thyroiditis.

The detection of anti-TPO during pregnancy indicates the mother's risk of developing postpartum thyroiditis and a possible impact on the development of the child.

At low concentrations, anti-TPO can occur in 5-10% of the healthy population and in patients with diseases not associated with the thyroid gland, such as inflammatory rheumatic diseases.

The anti-TPO titer increases with treatment with estrogen-progesterone drugs and taking drugs that affect the nature of the immune response.

INDICATIONS FOR ANTI-TPO DETERMINATION

Autoimmune thyroiditis,

Prediction of the risk of hypothyroidism with an isolated increase in TSH levels,

Ophthalmopathy: enlargement of the periocular tissues (suspicion of “euthyroid Graves’ disease”).

Neonates: hyperthyroidism and high anti-TPO levels or maternal Graves' disease,

Risk factor for thyroid dysfunction during therapy with interferon, interleukin-2, lithium drugs, cordarone,

Risk factor for miscarriage and failure of fertilization.

REFERENCE LIMITS – 0 – 30 mU/ml.

ANTIBODIES TO THE MICROSOMAL FRACTION

(ANTI-MF)

Autoantibodies to the microsomal fraction are detected in all types of autoimmune thyroid diseases, however, they can also be detected in healthy people. Anti-MF are a cytotoxic factor that directly causes damage to thyroid cells. Microsomal antigen is a lipoprotein that makes up the membranes of vesicles containing thyroglobulin. Autoimmune thyroiditis is a disease that is characterized by the formation of antibodies to various components of the thyroid gland with the development of its lymphoid infiltration and proliferation of fibrous tissue. Anti-MF can destroy the thyroid gland and reduce its functional activity.

DISEASES AND CONDITIONS IN WHICH CHANGES IN ANTI-MF LEVEL ARE POSSIBLE

The highest levels of anti-MF are found in patients with Hashimoto's AIT (95% of patients), idiopathic mexidema, last stage chronic atrophic thyroiditis, especially in elderly women, are quite common in patients with an identified untreated form of Graves' disease. Anti-MF are detected in 85% of patients with DTG, which indicates its autoimmune genesis. Anti-MF are sometimes detected in thyroid cancer. Increased levels anti-MF during the 1st trimester of pregnancy indicates a certain degree of risk of postpartum thyroiditis.

INDICATIONS FOR ANTI-MF DETERMINATION

Hashimoto's thyroiditis,

Autoimmune nature of thyroid diseases,

Prognosis of postpartum thyroiditis in high-risk women

There is a high risk of developing thyroiditis with a hereditary predisposition to this disease, with other forms of autoimmune processes ( diabetes type 1, Addison's disease, pernicious anemia).

ANTIBODIES TO TSH CRESEPTORS(TTT- RP)

Thyroid-stimulating hormone receptors are membrane structures of thyrocytes (and, possibly, cells of other organs and tissues). TSH-RP are regulatory proteins integrated into the thyroid cell membrane and influencing both the synthesis and secretion of TG and cell growth. They specifically bind pituitary TSH and ensure the implementation of its biological action. The cause of the development of diffuse toxic goiter (Graves' disease) is considered to be the appearance in the blood of patients of special immunoglobulins - autoantibodies that specifically compete with TSH for binding to thyrocyte receptors and can have a stimulating effect on the thyroid gland, similar to TSH. Detection of high levels of autoantibodies to TSH receptors in the blood of patients with Graves' disease is a prognostic harbinger of disease relapse (sensitivity 85% and specificity 80%). Fetoplacental transfer of these antibodies is one of the causes of congenital hyperthyroidism in newborns if the mother suffers from Graves' disease. To obtain evidence of the reversible nature of the disease, laboratory monitoring is necessary, aimed at establishing the elimination of antibodies to TSH-RP from the child’s body. The disappearance of antibodies in a child after drug-induced achievement of euthyroidism and elimination of goiter serves as the basis for deciding whether to discontinue drug therapy.

Autoantibodies to TSH receptors in increased quantities can be detected in patients with Hashimoto's goiter and subacute AIT. The level of autoantibodies progressively decreases with drug treatment of these diseases or after thyroidectomy, which can be used to monitor the effectiveness of treatment.

INDICATIONS FOR PRESCRIPTION:

REFERENCE LIMITS: The level of autoantibodies to TSH receptors in serum is normally up to 11 U/L.

With prices for complexes laboratory research can be found in the "Services and Prices" section.

Take tests constantly in the same laboratory - and your doctor will approximately know your personal normal values ​​and any deviation from the norm will be immediately noticed by him.

1. Svetlana

Irina

Good afternoon Dmitry! Are there ways to cure AIT and is it possible to take metformin with such a diagnosis?
Thank you in advance.

1. Dmitry Veremeenko

   Metformin is okay. It is theoretically possible to cure. There is no medical treatment yet

Iskander

Good afternoon, Dmitry.
Comment on iodine intake. Didn't find information on the site.
As far as I understand, a significant part of Russia is iodine deficient. Considering that iodized salt is one of the sources of iodine, and also that salt intake is recommended to be limited to a minimum (at least for people with high blood pressure), is there any point in taking it additionally for children and adults? Thank you.

1. Dmitry Veremeenko

   If the endocrinologist did not prescribe thyroid hormones based on tests, then no.

Dmitry Veremeenko

2004, University of Calcutta, India. Plants produce many toxic substances to protect themselves from insects and other herbivores. Many foods can be toxic to the thyroid gland. These substances are called goitrogens, and the chemicals responsible for this effect are called goitrogens. Goitrogenic substances suppress thyroid function. They interfere with the production of thyroid hormones. As a result of a compensatory mechanism, the thyroid gland will enlarge to counteract the decrease in hormone production. This enlargement of the thyroid gland is called a goiter. List of foods containing goitrogenic substances: cabbage, broccoli, Brussels sprouts, cabbage, cauliflower, greens, horseradish, mustard greens, peaches, peanuts, pears, pine nuts, radishes, rutabaga, soybeans, strawberries, flax seeds, almonds, apples, cherries, nectarines, plums. Cooking can reduce goitrogenic substances in foods. Boiling them in water for up to half an hour almost completely destroys them. Dietary intake of iodine (iodized salt) is able to overcome the effect of cyanogenic glycosides in moderate amounts in cruciferous vegetables. But this may not help if you eat a lot of cruciferous vegetables. Soy can cause autoimmune thyroid disease and is often associated with food intolerances. Thyroid peroxidase, thyroid peroxidase (TPO), is an enzyme expressed primarily in the thyroid gland. Catalyzes two important reactions in the synthesis process thyroid hormones: iodination of tyrosine residues of thyroglobulin and fusion of iodotyrosines in the process of synthesis of thyroxine and triiodothyronine.
ncbi.nlm.nih.gov/pubmed/15218979

2018, Shandong University, China. A high fat diet (for 18 weeks) rich in saturated and monounsaturated fatty acids causes abnormal thyroid lipid profiles and hypothyroxinemia in male rats. At the same time, free thyroxine T4 is reduced, and thyroid-stimulating hormone (TSH) increases.
ncbi.nlm.nih.gov/pubmed/29363248

2016, India. Risk factors for hypothyroidism:
Excess iodine. Iodine can also have a direct toxic effect on the thyroid gland through oxygen free radicals and immune stimulation.
Naturally occurring goitrogens are found in cabbage, cauliflower, broccoli, turnips, and cassava root forms. Soy or soy fortified foods can also worsen thyroid problems by decreasing the T4 hormone, increasing autoimmune diseases thyroid gland.
Thyroid peroxidase (TPO) activity can be increased by consumption of polyunsaturated omega-3 fatty acids (fish oil) and monounsaturated omega-9 fatty acids ( olive oil), while TPO activity is reduced by saturated and polyunsaturated omega-6s ( linseed oil) fatty acids.
Thyroid function can be impaired by high consumption of green tea. In rats, there is a significant decrease in serum T3 and T4 and an increase in TSH levels, along with a decrease in TPO.
A review of 14 studies found that while soy protein and soy isoflavones do not interfere with normal thyroid function in people with adequate iodine intake, they may interfere with the absorption of synthetic thyroid hormone, causing the hormone dose to be increased.
Peanuts can also cause goiter, but this effect is inhibited by a small amount of potassium iodide.
Wheat bran inhibits TPO activity.
Selenium and vitamin B12 deficiency are also implicated in autoimmune thyroiditis.
UV filters to protect the skin from ultraviolet radiation may also alter thyroid homeostasis.
ncbi.nlm.nih.gov/pmc/articles/PMC4740614

1. Alexander

   Dmitry, now it turns out that you don’t eat, for example, Broccoli and all the cabbage, but what about Sulfarafan?

   1. Dmitry Veremeenko

      Eat. It’s just that if TSH rises above normal, you need to consider iodine and selenium supplements with an endocrinologist. They help fight it

2. Alexander

   What is the conclusion from all this? It’s already scary to live.

   1. Dmitry Veremeenko

      What is the conclusion?

L.B.

Dmitry, does this mean that if you have AIT, it is undesirable to eat broccoli? I wouldn't want to give it up completely.

1. Dmitry Veremeenko

   AIT means you are on hormones. If you are on hormones, then you don’t care anymore. Only soy causes an increase in hormone levels

Heat

My TSH is 6.5, all other thyroid indicators are within normal limits.
I think that if TSH remains as it is, this is only a plus; for example, the pulse, including from such TSH, is low at rest with good health and a normal ECG.

1. Dmitry Veremeenko

   What are your autoimmune markers and how old are you?

   1. Heat

      My autoimmune markers are not elevated, AIT has not been diagnosed. Inflammatory markers are also low (C-reactive protein fluctuates last years from 0.1 to 0.2). True, endocrinologists do not like such TSH, they prescribe to drink Iodomarin, and some of them even take hormones, although my hormones T4 and T3 are in the middle of the norm, although if I had listened to doctors, I would have become disabled 20 years ago.
      By age and health, I belong to the 8th version of the anti-aging plan indicated here.

      I think my TSH is elevated - because I rarely eat and eat a lot of vegetables, including the cruciferous family, I eat little protein, but a lot of fat, I walk a lot and quickly every day. If my TSH does not rise further, then I see in such a current TSH - only a plus.

      1. Dmitry Veremeenko

         From such TSH at your age there can be nodes and even tumors of the gland. Low doses Iodine is still worth taking. I will write an article about this soon

         1. Heat

            Dmitry, this is of course a double-edged sword. On the one hand, a relatively high TSH slows down aging, but carries the risk of overgrowth of the thyroid gland, and if T4 and T3 fall below the norm, there is a risk of atherosclerosis. On the other hand, low TSH accelerates aging, while it may seem to a person that he is full of strength and energy, but he will age faster.

            So it turns out and you need to maneuver so that TSH is not low and at the same time T4 and T3 do not fall below the norm, and iron does not grow.

            Yes, and I also saw evidence that taking iodine in the form of iodized salt or supplements like Iodomarin increases the risk of AIT, apparently such inorganic iodine acts more quickly and strongly than iodine from food, which can contribute to the onset of AIT and this is with normal TSH and hormones, so those taking additional iodine in the form of supplements are recommended to get tested for thyroid antibodies more often.

         2. Dmitry Veremeenko

            About the risks of iodine - this is true. It would be best to get tested for iodine. And if it is in short supply, then a small dose is normal.

Tatiana

Dmitry, please explain why the article and comments talk about TSH as an autonomous indicator? I’m used to thinking that its level depends on the level of thyroid hormones: if they are high, it is low, if they are low, it rises and its increase stimulates the work of the thyroid gland. Or is it not that simple?

1. Dmitry Veremeenko

   Because t3 and t4 are unstable. And TSH is more stable. Many endocrinologists generally only look at it.

   1. Tatiana

      Thank you! Then the situation is clear. I tested it in Helix 2 times with an interval of 2 weeks, the TSH levels are very different. One endocrinologist diagnosed hypothyroidism (TSH was 2 times higher than normal), and the second laughed and said that this does not happen in such a short period, a change in TSH can occur no more than 3 months. I re-tested at Invitro - TSH is normal. — By the way, this is about the quality of Helix’s work.

      1. Dmitry Veremeenko

         Apparently you took beta blockers the day before???)))

Galina

Good afternoon. Dmitry. Please tell me if I need to take iodine, if
TSH -0.5, and T4 - 12.7 and T3 - 3.36?

1. Dmitry Veremeenko

Lydia

Hello Dmitry! I am 24. My indicators are: TSH - 1.15 mU/l (reference values: 0.4-4.0), T4 st. - 12.84 (9.00-19.05), AT-TPO - 14.3 U/ml (<5,6). Есть узел (диагноз — аденоматозный зоб). Пока что никакое лечение эндокринологом мне не назначено, показано только следить за Т4 ,ТТГ и узлом. Меня интересует, реально ли понизить/не допустить дальнейшего повышения антител? Если да, то как? И нужно ли что-то делать в моей ситуации, например, придерживаться какой-либо диеты или что-либо ещё? Если да, то какие это могут быть рекомендации?

1. Dmitry Veremeenko

Galina

good afternoon Dmitry.
TSH -0.5, and T4-12.7 and T3-3.36
According to hair analysis using the method of D. Skalny, my selenium is 0.479 (0.2-2)
iodine 6.87(0.15-10) zinc at the lower limit 142(140-500)
low iron 13.22(7-70)
lithium is increased 0.309(- 1) do I take it once a week?
So should I give up lithium and take extra zinc?
But selenium and iodine are not needed?
Should I not take Thyroid Energy?

1. Dmitry Veremeenko

   There is no need to give up lithium; 1 tablet per week will not have any effect.
   Zinc is additionally needed if it is significantly below the norm. And that's not necessary

Anastasia

Good afternoon. I really want to know how to lower TSH levels without hormones.
I took tests and was horrified. Tsh = 65.71 IU/l, and T4 = 8.80.

1. Dmitry Veremeenko

Nina

Dmitry, hello, I’m 75 years old, there are nodes on the thyroid gland (they don’t grow), at first TSH was not very elevated, but after taking cordarone (a drug for arrhythmia with iodine) for a year, TSH rose to 10, the drug was canceled, trioxin 25 was prescribed - 50 mg. 2 years have passed, TSH is still elevated 7-8 while taking hormones. What will you advise, the doctor only increases the dose of L-thyroxine and does not give direction for the analysis of other hormones?

1. Dmitry Veremeenko

   TSH at 75 years old is normal TSH for a centenarian

Nina

Dmitry, thanks for the answer, I didn’t understand what kind of TSH is normal at 75, and is it necessary to drink hormones?

1. Dmitry Veremeenko

   A 2011 study from the Leiden University Medical Center (Netherlands) confirmed the findings of a previous study. Subclinical hypothyroidism is not associated with a risk of increased overall mortality unless it is of an autoimmune nature. Moreover, there is no association between subclinical hypothyroidism and coronary artery disease, heart failure, or CVD mortality unless TSH levels are greater than 10 mU/L.
   
   Women over 65 years old TSH norm 0.42–7.15 mU/l (as in centenarians), but control of cholesterol and inflammation markers.
   —
   If you are 65 years of age or older, if your thyroid hormones are normal, and only the TSH hormone is elevated no higher than 10 mU/L, then treatment to lower TSH below 10 mU/L is not required, and, quite possibly, may only shorten life. The only requirement is to monitor cholesterol levels and inflammatory markers (C-reactive protein and interleukin-6).
   In your case, hormones allow you to control TSH no higher than 10 - that’s good. Just make sure that cholesterol and inflammatory markers (c-reactive protein and interleukin-6) are not high.

Tatiana

Hello! and if the thyroid gland is normal and TSH is 12... and if you feel well... do you need to take hormones? I’m now 47...from the age of 30 I was elevated...I refused to take hormones...and I was slim and felt good...from 44 I started drinking 50 and gained 10 kg..my skin became worse...so it turns out that until I didn’t drink everything was fine... and the point of drinking them... I should have refused... but I want to believe the doctors.

1. Dmitry Veremeenko

   According to research, it is necessary

Maksim

Dmitriy! I had my thyroid tested for the first time today.
Where to run!!!

TSH - 7.8300 mIU/l (reference 0.350 - 5.500)
T3 - 1.15 nmol/l
FT3 – 2.58 pg/ml
T4 - 61.2 nmol/l
FT4 - 9.77 pmol/l (reference 11.50 - 22.70)
AtTG - 251.6 IU/ml (reference 0.0 - 60.0)
AtTPO - 5600.6 IU/ml (reference 0.0 - 60.00)!!!

I especially liked the last indicator!
I couldn't even find this on the Internet.

ULTRASOUND STUDY OF THE THYROID GLAND WITH CDC AND
REGIONAL L/UNITS
Acoustic access, location: The thyroid gland is located typically, the contours are smooth,
clear, heterogeneous cellular structure. Cystic and solid formations
not found; the gland capsule can be traced throughout.
Dimensions: right lobe: width - 16 mm, thickness -18 mm, length - 46 mm
volume –7.1 cm3
left lobe: width - 18 mm, thickness - 19 mm, length - 43 mm
volume –8.0 cm3
isthmus: 4 mm
The total volume is 15.1 cm3, does not exceed the age norm.
The vascular pattern of the gland parenchyma in the Color Doppler mode is enhanced.
Topographic-anatomical relationship of the thyroid gland with muscles and
organs of the neck are not changed. Regional l/nodes without features.
CONCLUSION: Ultrasound – signs of diffuse changes in the structure of the thyroid
glands of the AIT type.

I also did biochemistry, everything is normal there as always:
C-protein ultra - 0.27
Cholesterol - 4.67
Glyc.hemoglobin 5.20%
etc. more than 20 indicators, they are all within reference limits.

(54 years old, 70 kg, 185 cm, BMI 20-21, navel waist 85-86, early bird - lights out at 10pm, gets up at 5am)

1. Dmitry Veremeenko

   See an endocrinologist and start taking hormones.

   1. Maksim

      Thank you, Dmitry!
      I've already signed up!
      Can raw broccoli be harmful? Should I stop eating it every day?

      1. Dmitry Veremeenko

         Can’t unless you eat more than 100 grams per day

Maksim

Dmitry, I visited an endocrinologist, to my surprise, she said that we won’t do anything, after 3 weeks we’ll have to take all the thyroid tests again. I felt the thyroid gland, said that there was a nodule on the left, 2 ultrasound doctors came, one said - a pseudonodule, the other - a normal node, they immediately took a sample for cytology and tumor markers of the thyroid gland. There the norm is: thyroglobulin - 17.4 ng/ml (reference 0.2-70.0) and calcitonin less than 2.00 pg/ml (reference 0.4 - 27.7). I'm waiting for the results of iodine-zinc-selenium from blood plasma.

1. Maksim

   The results came: not enough iodine and zinc,
   and selenium - before the analysis, for about 3 weeks, I ate 3 Brazil nuts. in a day

   Study Result Units Reference values
   Iodine (serum) 0.042* mcg/ml (0.05 – 0.10)
   Selenium (serum) 0.104 mcg / ml (0.07 - 0.12)
   Zinc (serum) 0.613* mcg/ml (0.75 - 1.50)

   Maybe I'm wrong
   but I like it better when you first take tests,
   and then you take vitamins, and not vice versa.

Maksim

And the cytology is ready: nodular colloid goiter, benign. image. according to Bethesda -II diagnostic category.
Dynamic observation is recommended.

I read on the Internet - taking into account the analyzes - there is little iodine. I'm going to eat seaweed!

1. Maksim

   I visited the doctor again. Iodomorin 200 mcg x 1 tablet was prescribed. per day x 3 months and Aquadetrim 2500 IU every day.
   They said that an analysis of D3 may show that there is a lot of it, but it is not a fact that the body uses these reserves correctly.
   This is indirectly shown by a test for parathyroid hormone.

   They also said that such a node (16 mm) will most likely remain so, will not increase, but will not decrease either.

Julia

Good day everyone!
Can anyone advise on how to increase free T3? At the moment I have it = 3.1. T4 and TSH are within normal limits, but the T3 to T4 ratio is below normal.
Thank you

Lyudmila

Dmitry, please specify where I can read in more detail about the increased risk of atherosclerosis with low T4 and T3?
Also, in the comments somewhere you wrote about the effect of taking the synthetic hormone T3 on papillomas. This information is really needed. Please give me links or a tip where I can read this.
Thank you very much

1. Dmitry Veremeenko

   ncbi.nlm.nih.gov/pubmed/18443261

Olga

Dmitry, hello. Please advise whether I need to take hormones - TSH-4.46 (normal 0.4-4.2), chol.-4.58, react protein 0.09, rheumatic factor 3.7 (0- 14), glycerated hemoglobin - 5%, atherogenic coefficient - 2%, glucose 4.38. age 55 years. thank you.

1. Dmitry Veremeenko

Olga

Let me add that in 8 months the ttg increased from 3.16 to 4.46.

1. Dmitry Veremeenko

   This is a question for an endocrinologist.

Elena

Good afternoon, my TSH is 1.97. I'm using commas! The algorithm shows an excess, although the norm is 0.4-4.5. This is mistake???

1. Dmitry Veremeenko

   I just entered 1.97 into the algorithm - that is, separated by commas. Everything is working. No excess. Perhaps you don’t have Excel, but open the algorithm through Open Office?

Aida

Hello Dmitry! The article is very informative, thank you very much. In 2010, I had an operation - mastectomy (cancer of the left breast pT2NOMO. NALT, ME dated June 29, 2010. 4 courses of APCT according to the FAC regimen. I did not take harmonium-containing or other drugs. Medical examination was carried out according to plan. In 2017, an ultrasound scan of the thyroid gland showed volume 1 .9 cm3, homogeneous tissue, low echogenicity, medium-grained. I work out in the gym - strength training. Weight at 53 years old - 56.5 kg. I feel great. I recently underwent examinations: ultrasound - thyroid gland volume 4.5 cm3, homogeneous, but already coarse-grained. Conclusion: hypoplasia of the thyroid gland. Hypothyroidism?
Tested for hormones: TSH (III generation) 7.65 at 0.46-4.7 mlU/L; Free thyroxine T4 - 10.65 at 8.9 - 17.2 pg/ml; Free triiodothyronine T3 - 4.73 at 4.3-8.1 pmol/l; Prolactin 443.7 at 64-395 mlU/l; Antibodies to Thyroid Peroxidase (AT-TPO) >1000.0 at 0-35 IU/ml.
They could explain and give recommendations. Thank you.

1. Admin_nestarenieRU

   Enter your data here and the algorithm will tell you
   http://not-aging.com

Olesya

TSH 1.51 mU/l age 37 years. Please tell me this is the norm?

1. Dmitry Veremeenko

   This is fine

   1. Olesya

      Thank you, you reassured me.

Dmitry Veremeenko

The question is not clear to me. Which is fundamentally wrong. Where are the research links?

Paul

In fact, only 7 subjects out of 40 developed antibodies when taking additional iodine, and this may be because there was not enough selenium. And again, you need to understand that these are people with ALREADY EXISTING autoimmune thyroiditis. There, in addition to iodine deficiency, there are a bunch of other associated diseases and simply adding additional iodine does not will you help? It’s like with calcium supplements. That is, you are talking about hypothyroidism, but you cite as evidence a study of people with For example, long-term iron deficiency leads to depletion of the thyroid gland and vice versa. Here the connection is like this. For the absorption of iron, good acidity of the stomach is needed, and this is provided by the thyroid gland. With a lack of T3 and T4, a decrease occurs acidity due to insufficiency of parietal cells Castle factor is a product of the activity of these cells. Is it clear where B12 deficiency comes from? And B12, in turn, is a cofactor for the absorption of iron along with vitamin C, etc. Further, due to the low level of ferritin, the enzyme deiodinase is blocked (converts low-active T4 into active T3) The enzyme thyroid peroxidase is also iron-dependent. The biological effect of thyroid hormones is reduced - hello, HYPOTHYROISIS So many women and children suffer from anemia! And they are offered to live with hypothyroidism and not take iodine in the form of supplements So you tell me what to do Otherwise, the whole article is about not taking iodine
And you need to do this: Run and run to take tests for B12, ferritin, iron, TSH, ATPO-TG, free T4, zinc, ctkty and eliminate all deficiencies

1. Dmitry Veremeenko

Catherine

Good afternoon, TSH 3.54, free T3 2.52 pg/ml, free T4 0.908 ng/dl. Age 40. Should I contact an endocrinologist or is everything within normal limits? Thank you.

1. Dmitry Veremeenko

   and how much T3 and T4 are in pmol/l?

   1. Catherine

      I have indicators in such units, but I found the conversion coefficients and calculated them. It turns out T3 - 3.87 pmol/l, T4 - 11.69 pmol/l.

      1. Dmitry Veremeenko

         Then this is subclinical hypothyroidism. That is, not yet hypothyroidism. It is worth monitoring cholesterol, markers of inflammation, but it is not worth treating specifically.

         1. Catherine

            Thank you very much for the answer. It’s just that there are almost all the symptoms of hypothyroidism, and she’s already desperate to lose weight despite the constant monitoring of nutrition and exercise. gym. But that means that this is not the reason.

         2. Larisa

            Dmitry, my TSH is 3.03. T4 is normal. They prescribed Eutirox 25 mg, which made me feel really bad. She stopped drinking it herself. Tell me what “markers of inflammation” means. After the dental implant surgery, I have a slightly increased content of both leukocytes and erythrocytes. What to do? I am 60 years old.

         3. Dmitry Veremeenko

            It is absolutely impossible to reduce TSH 3.03 at your age. At your age, if the thyroid hormones are normal, and only the TSH hormone is elevated no higher than 10 mU/l, if at the same time you do not have elevated antibodies to the thyroid gland (there is no autoimmune process), then treatment, judging by the data in this article, is not is required and, quite possibly, can only shorten life. The only requirement is to monitor cholesterol levels and inflammatory markers (C-reactive protein and interleukin-6).
            ncbi.nlm.nih.gov/pmc/articles/PMC4480281

OlegZ*

Dmitry, please tell me, what is the point of including an analysis for interleukin 6 in DNAOM in the panel, if according to the open longevity norm this indicator (indicated in the algorithm) should be less than 1.07 pg/ml, and DNAOM can only give an approximate result “<2". Может, стоит дождаться когда они подтянут свои возможности к нашим потребностям?

The prevalence of thyroid diseases is increasing every year. Therefore, people interested in maintaining their health regularly take iodine preparations for prevention and visit the laboratory once a year to find out the result of their blood test for thyroid-stimulating hormone. This helps them control the situation, and if necessary, they have the opportunity to consult a doctor in time and undergo a proper examination.

If you experience any complaints from the nervous system (weakness, impaired concentration, memory loss, drowsiness, hyperexcitability, etc.), you should consult a doctor and not self-medicate.

And one of the specialists you need to visit will be an endocrinologist. He will refer the patient for an appropriate examination, and if the result is the normal level of the TSH hormone, then treatment will need to be done by a neurologist. If there are deviations, then the endocrinologist will continue therapy.

Much depends on the coordinated functioning of the endocrine system. With a lack or excess of hormones, complaints about well-being appear immediately. Thyroid-stimulating hormone (TSH) plays a large role in the chain that controls the functioning of the thyroid gland.

If this chain is broken, then problems appear - hypothyroidism (low thyroid function) or hyperthyroidism (increased thyroid function). A TSH hormone test allows you to determine its amount, so the doctor can make a diagnosis.

Thyroid-stimulating hormone stimulates work. If there is little thyroxine (T4) and triiodothyronine (T3) in the blood, then the amount of TSH increases greatly. If T4 and T3 are sufficient, then TSH decreases.

If you take a blood test for TSH in a “decent” laboratory, then reference values ​​will always be indicated in a specially designated line. This is the range within which a normal result should be.

If the result is higher or lower than normal (in the case of the thyroid gland, you should be wary if it is on the border of normal), then you should definitely consult a doctor. Typically, thyroid-stimulating hormone is 0.4-4.0 µIU/ml.

Sometimes laboratories provide other data, in which the normal result ranges from 0.8-1.9 µIU/ml. In such cases, we are talking about determining TSH using an ultrasensitive method.

Women have to visit an endocrinologist somewhat more often during their lives than men. This is due to the fact that problems with the menstrual cycle, and, accordingly, childbirth, are becoming more common every year.

If the TSH norm in women during examination is within the reference range, then the cause of reproductive dysfunction lies in some other problem.

Recently, it has been generally accepted that the lower the TSH, the better. An indicator at the upper limit of normal 3.5-4.0 µIU/ml may already indicate a latent course of hypothyroidism. Therefore, if there are relevant complaints, the doctor may prescribe treatment, even if the TSH result is within standard limits.

In such cases, there is no need to worry, and we must remember that each person is individual. What is normal for one is pathological for another.

Small doses of L-thyroxine will improve the functioning of the thyroid gland, and the norm of the TSH hormone in women will be closer to the lower limit. If against this background the complaints went away and, in particular, pregnancy occurred, then the doctor’s assumptions turned out to be correct.

The result of such a trial treatment should be assessed no earlier than three to four months, since the body needs time to adapt to the new amount of thyroid hormones in the blood.

When interpreting thyroid hormone tests, the doctor should always consider the patient's general condition. Particular attention is paid to pregnant women.

In the first trimester, they must undergo a blood test for TSH, since even hidden hypothyroidism or hyperthyroidism can harm the developing fetus. in the first trimester it is 0.4-2.0 µIU/ml.

Normal TSH in men

Men see an endocrinologist much less frequently and at a later age. This is due to the fact that genetically they are less predisposed to thyroid diseases. Any examination by an endocrinologist should begin with an ultrasound, a blood test for TSH and thyroid hormones (T3 and T4).

It is also useful to know your TPO antibody levels. The TSH norm in men is the same as in women and is 0.4-4.0 µIU/ml. In the presence of nodes, changes in TSH analysis and a high level of antibodies to TPO, a puncture of the thyroid gland should be performed under ultrasound guidance.

Normal TSH in children

When diagnosing congenital hypothyroidism in a child, this is the task of neonatologists in the maternity hospital. They conduct screening to detect this disease, since in this case, timely treatment is the only chance to get a positive result.

Otherwise, children become disabled, as they develop in conditions of severe lack of thyroid hormones.

TSH norm in children, µIU/ml:

• in newborns – 1.1–17;
• in children up to 2.5 months – 0.6–10;
• in children under 2 years old – 0.5–7;
• in children under 5 years old – 0.4–6;
• in children under 14 years of age – 0.4–5;
• in children over 14 years old – 0.3–4.

In newborns, TSH is much higher than in adults. The older the baby gets, the better his thyroid gland works. The amount of T3 and T4 hormones increases, and TSH gradually decreases. By the age of 14, the reference range levels out and becomes like that of an adult.

Decoding TSH

If you suspect a thyroid disease, you should contact a therapist or endocrinologist. The doctor will refer you for an appropriate examination, which will help determine the diagnosis.

Decoding TSH does not seem so difficult if you understand the principle of feedback between the thyroid gland and the pituitary gland. If we approach this issue more simply, then a high TSH indicates reduced thyroid function (hypothyroidism). A low TSH, on the contrary, indicates increased production of thyroxine (hyperthyroidism).

When interpreting the analysis, it should be remembered that hypo- and hyperthyroidism are only syndromes that accompany certain diseases.

For example, hypothyroidism often occurs with autoimmune thyroiditis, and hyperthyroidism often occurs with diffuse toxic goiter. But these diseases can mask thyroid cancer.

Therefore, if on ultrasound the lump has characteristic signs of cancer or nodes more than 10 mm in diameter, it is necessary to perform a puncture biopsy to exclude this serious disease.

An integrated approach to examination and treatment will help to identify the disease in time and stop its progression. If the blood test for TSH and free T4 is normal, then most likely there are no problems with the thyroid gland.

But doing an ultrasound will not be superfluous, since this method shows the structure of the organ, but does not reflect its function. Determination of hormonal levels in addition to ultrasound examination is the “gold” standard for diagnosing thyroid diseases. Therefore, they should not be neglected.

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