Thyreopathy

In the structure of thyroid pathologies, thyreopathy occupies a special place - a disease that can be accompanied by both hyperthyroidism and hypothyroidism. The pathogenetic mechanism of thyreopathy is complex, often associated with autoimmune processes and type 1 diabetes mellitus. In this regard, the disease can have a different clinical picture. Treatment is based on the identification of the causes of pathology and involves individualized complex treatment. [1]

Epidemiology

If we believe the world statistics, thyreopathies occur in almost 30% of people on the planet. The most common conditions are euthyroidism, but today the percentage of autoimmune thyroid pathologies is increasing.

Intensive growth of morbidity is noted in regions with iodine deficiency. The number of hypothyroidism patients has increased approximately 8 times over the last 15 years. This indicator is associated not only with the spread of thyreopathies, but also with the improvement of the quality and availability of diagnostic measures.

According to some data, thyreopathy is more often suffered by women, although the male population is not bypassed by the pathology.

The pathology is particularly unfavorable in women and children. In female representatives of the female sex, multiple hormonal disorders are noted, the monthly cycle is disrupted, infertility develops. In childhood, thyreopathy can lead to impaired mental performance, inhibition of skeletal development, damage to internal organs.

Causes of the thyreopathies

Thyreopathy can develop due to such pathologic causes:

• improper production of thyroid hormones;
• a significant weakening of immune defenses;
• oxidative stress with an imbalance between antioxidants and stressors in favor of the latter, resulting in the formation of free radicals in the body;
• intoxication, accumulation of toxic substances and free radicals in tissues;
• failure of vital organs and body systems.

Thyroidopathy can manifest as hyperthyroidism (thyrotoxicosis), [2] hypothyroidism (decreased thyroid function), or euthyroidism (nodular goiter). [3]

Risk factors

An increased risk of developing thyreopathy is present in such categories of patients:

• women and the elderly (over 55-60 years of age);
• people with an aggravated hereditary history of thyroid pathologies;
• Patients with autoimmune diseases (particularly type 1 diabetes);
• Patients who have been treated with radioactive iodine or antithyroid drugs;
• people who have been exposed to radiation;
• patients who have undergone surgical intervention in the thyroid gland;
• a woman during pregnancy or an imminent repeat pregnancy.

Pathogenesis

Thyroid gland is one of the most important organs of the endocrine system. Its follicles produce hormones that take part in all biological reactions that take place in the human body.

The thyroid gland produces thyroid hormones such as triiodothyronine T3 and thyroxine T4, which influence the functionality of all organs and systems, control cellular growth and cell and tissue repair. Hormonal synthesis starts in hypothalamus - the highest regulator of the neuroendocrine system, localized in the basal part of the brain. Here there is a production of riling hormone, which, in turn, "pushes" the pituitary gland to produce TTG - thyroid hormone. Through the circulatory system, TTH reaches the thyroid gland, where T3 and T4 are produced (provided there is an adequate amount of iodine in the body).

If there is iodine deficiency, or a person lives in unfavorable environmental conditions or has a poor (monotonous) diet, hormone production is upset and pathological reactions develop in the thyroid gland - thyreopathies. Practicing physicians classify thyreopathies as indicators of environmental problems. According to some reports, this disorder is more common than other endocrine diseases, including diabetes mellitus. [4]

Symptoms of the thyreopathies

The symptomatology of thyreopathies is directly dependent on the functional capacity of the thyroid gland.

When the function of the organ is overactive, it can be observed:

• sleep disturbance, excessive excitability, nervousness;
• tremors in the hands, excessive sweating;
• weight loss against the background of increased appetite;
• increased defecation;
• joint and heart pain;
• inattention, absent-mindedness.

When thyroid function is insufficient, patients complain of:

• lethargy, bad mood;
• dry skin, swelling;
• deterioration of hair and nails;
• change in appetite;
• a drop in mental alertness;
• malfunctions of the monthly cycle (in women);
• a tendency to constipation.

Against the background of diffuse overgrowths of the tissues of the organ and normal indicators of hormone levels may appear complaints of:

• constant emotional instability;
• insomnia;
• unpleasant sensations in the throat area (lump, fever, discomfort when swallowing food or liquid);
• pain and tightness in the neck;
• visual enlargement of the front of the neck;
• a constant feeling of fatigue for no apparent reason.

Amiodarone-induced thyreopathies

Amiodarone is a representative of antiarrhythmic drugs, which is characterized by the increased presence of iodine. With prolonged use of this medication, a number of side effects occur, among which is the so-called amiodarone thyreopathy.

One tablet of Amiodarone 0.2 g contains 0.075 g of iodine. After metabolic transformation of the tablet in the body, 0.006-0.009 g of inorganic iodine is released, which is about 35 times higher than the physiological human requirement for this trace element (daily norm for an adult is about 200 µg, or 0.0002 g).

Prolonged treatment with Amiodarone leads to accumulation of iodine in tissues, which is accompanied by an increased load on the thyroid gland and impairment of its functions.

Thyroidopathies can occur either as thyrotoxicosis, or as hypothyroidism.

Autoimmune thyreopathy

The essence of autoimmune thyreopathy lies in the fact that the immune system activates the production of antibodies against the protein structures of the body. This can be triggered by both congenital predisposition to such failures and viral infection, which has a protein structure similar to the proteins of thyroid cells.

At the beginning of the disease, there is an increase in the levels of antibodies to the thyroid gland, without antibodies destroying the organ. The pathology can then proceed in two scenarios:

• or the processes of destruction of glandular tissues will begin against the background of normal hormonal production;
• or the gland tissue is destroyed, hormone production decreases dramatically, and hypothyroidism develops.

Autoimmune thyreopathy is rarely accompanied by intense symptomatology. Often the pathology is detected accidentally, during preventive examinations. Although some patients still complain of a periodic feeling of discomfort in the front of the neck. [5]

Complications and consequences

The consequences of thyreopathies are different, which depends on the initial pathology, on the features of the lesion of the thyroid gland, on the completeness and effectiveness of treatment. Most often patients indicate such disorders:

• weight gain despite proper nutrition and sufficient physical activity;
• drastic weight loss despite increased appetite;
• apathy, depression, depression;
• swelling (near the eyes, on the extremities);
• decreased performance, impaired memory and concentration;
• seizures;
• body temperature instability;
• women's menstrual irregularities;
• panic attacks;
• heart rhythm disturbances.

Thyroidopathies are often accompanied by anemia, difficult to correct. Many patients with increased thyroid function have photophobia, lacrimation. It is possible to worsen the course of the underlying cardiovascular pathology.

In the acute course of thyreopathy, the risk of developing cardiac crisis conditions increases. The crisis makes itself known by intense tremor of the extremities, digestive disorders, fever, a sharp drop in blood pressure, tachycardia. In severe cases, there is a disturbance of consciousness, the development of coma.

Induced thyroidopathies are not always transient: in some cases, thyroid function does not recover and autoimmune malfunctions become persistent and permanent.

Diagnostics of the thyreopathies

Diagnosis directly thyreopathy and finding out the reasons for the development of pathology, first of all, are based on laboratory tests.

Tests may include:

• The study of TTG - thyroid hormone - is an indicator of the functional capacity of the thyroid gland. Analysis is necessary to determine the state of compensatory mechanisms, hyper and hypofunction of the organ. Normal value: 0.29-3.49 mMU/liter.
• The study of T4 - free thyroxine, the increase in the level of which occurs in hyperthyroidism, and the decrease - in hypothyroidism.
• Decreased T3, triiodothyronine, is characteristic of autoimmune thyreopathies, hypothyroidism, severe systemic pathologies, physical overload and exhaustion.
• The autoimmune thyroid hormone receptor antibody test helps diagnose autoimmune diseases, Bazeda disease.
• Analysis for antibodies to microsomal antigen (thyroid peroxidase) allows differentiation of autoimmune processes.
• Evaluation of thyrocalcitonin helps to assess the risks of oncopathologies.

Instrumental diagnosis may be represented by the following investigations:

• Ultrasound of the thyroid gland - helps to accurately determine the size of the organ, calculate its volume, mass, assess the quality of blood supply, establish the presence of cysts and nodular formations.
• Radiography of the neck and chest organs - allows to exclude oncologic pathology and pulmonary metastasis, to determine the compression and displacement of the esophagus and trachea under the influence of pruritic goiter.
• Computed tomography makes it possible to perform targeted biopsy of nodular masses.
• Scintigraphy is a radiologic study to assess the functional capacity of the gland.
• Magnetic resonance imaging - rarely used, due to low informativeness (quite replaced by conventional ultrasound).
• Biopsy - is indicated for all diffuse or nodular thyroid enlargements, especially when oncology is suspected.
• Laryngoscopy - relevant in tumor processes.

The scope of diagnosis is determined by the attending physician. Sometimes examination and palpation of the gland in combination with laboratory methods and ultrasound may be sufficient to make a diagnosis.

Differential diagnosis

Differential diagnosis is performed within such pathologies:

• Autoimmune thyreopathies:
  • Graves' disease (isolated thyreopathy, endocrine ophthalmopathy).
  • Autoimmune thyroiditis (chronic, transient form - painless, postpartum, cytokine-induced).
• Colloid proliferative goiter:
  • Diffuse euthyroid goiter.
  • Nodular and multiple nodular euthyroid goiter (with or without fynctional autonomy).
• Infectious thyreopathy:
  • Subacute thyroiditis.
  • Acute form of suppurative thyroiditis.
  • Specific thyroiditis.
• Tumors:
  • benign;
  • malignant.
• Hereditary (congenital) thyreopathy.
• Thyreopathies due to pathologies of other systems and organs.

Treatment of the thyreopathies

There are two basic types of treatment for thyreopathy - we are talking about conservative (drug) therapy and surgery.

Drug therapy, in turn, can be represented by the following options:

• In signs of thyrotoxicosis on the background of follicular destruction, thyreostatic drugs are avoided due to the lack of activation of hormonal synthesis. For therapeutic purposes, β-adrenoblockers, non-steroidal anti-inflammatory and corticosteroid agents are used.
• In hypothyroidism, thyroxine medications (e.g., L-thyroxine) are prescribed to restore adequate iodine hormone levels. The dynamics of thyroid function recovery is monitored, during which thyroxine may be canceled.
• Autoimmune thyreopathy often requires lifelong thyrostatic medication.

Amiodarone-induced thyroopathies are treated with long-term thyrotropics. The daily amount of Methimazole or Tiamazole is standardized at 40 to 60 mg in two doses, and Propylthiouracil is prescribed at 400 to 600 mg per day (in four doses). For rapid restoration of thyroid gland functionality, lithium carbonate can be used, which inhibits proteolysis and reduces the degree of release of already produced thyroid hormones from the gland. The drug is administered at 300 mg every 7 hours. The effectiveness of treatment can be assessed after a week. Cautiously use the drug lithium in patients with impaired cardiac muscle function. According to individual indications, surgical treatment or radioiodotherapy is prescribed. Radioactive iodine is used not earlier than six months or a year after completion of amiodarone administration.

Surgical treatment is indicated when drug therapy is ineffective and may consist of these interventions:

• Hemithyroidectomy - resection of part of the thyroid gland in the area of nodular or cystic masses.
• Thyroidectomy - complete resection of the thyroid gland, with preservation of the perithyroid glands.

After removal of the organ, postoperative hypothyroidism develops, requiring hormone replacement therapy.

Prevention

Preventive measures are recommended for people who are prone to developing thyreopathy - in particular, those who live in iodine-deficient regions.

• It is desirable to reduce the consumption of foods that interfere with the normal function of the thyroid gland (smoked meats, pickles, pickles, marinades, convenience foods) and add to the diet seafood, sea fish.
• If you are prone to hyperthyroidism, you should include beans, broccoli, different types of cabbage, soy, sesame, greens (including leafy greens) in your diet.
• With a tendency to hypothyroidism, it is important to minimize the consumption of sweets, muffins, sausages. Do not hurt in the diet of dairy products, vegetables and fruits.

A good solution for people living in conditions of iodine deficiency is the use of iodized salt. To ensure that the product does not lose its beneficial properties, you should adhere to the following rules:

• store salt in a clean container, closed with a tight lid, in dry and darkened conditions, avoiding direct sunlight;
• Salt only already cooked food or at the very end of cooking;
• avoid buying iodized salt without packaging.

In many cases, it makes sense to add foods that contain sufficient iodine to the diet. These are sea foods and algae, walnuts and pine nuts, eggs, cereals, beans, persimmons, cranberries, blackcurrants, rowanberries. If indicated, the doctor may prescribe additional intake of iodine-containing preparations.

If a person assumes that there are problems with the thyroid gland, he or she should immediately contact his or her family doctor or endocrinologist. The specialist will assess the condition of the organ and, if necessary, determine the subsequent monitoring and treatment tactics.

Forecast

Thyreopathy is most often amenable to drug correction, and when using a complete and competent approach to therapy does not cause deterioration in the quality of life and disability. With medication-induced thyreopathy, it is important to refuse to take provocative drugs, if possible replacing them with other analog means. If the current disease requires mandatory administration of provocative medications, the doctor should evaluate the ratio of the effect of therapy with the risks and probable consequences of thyreopathy. If it is decided to continue treatment, then the patient is necessarily and regularly monitored indicators of TTG, T4, AT to TPO, and at the end of the treatment course carry out measures to compensate for thyroid disorders.

Autoimmune thyroidopathy requires lifelong hormone replacement therapy.