Hypothyroidism is a clinical syndrome that develops due to long-term, persistent thyroid hormone deficiency in the body or with the development of resistance (resistance) to the hormone at the tissue level.
There are primary, secondary and tertiary hypothyroidism.
Primary hypothyroidism develops when the thyroid gland is damaged and is accompanied by an increase in the level of thyroid stimulating hormone – TSH.
Secondary hypothyroidism occurs when a specific part of the brain is affected — the hypothalamic-pituitary system — with insufficient secretion of thyroid-stimulating hormone and a consequent decrease in thyroid function.
Tertiary hypothyroidism develops when the hypothalamus is affected. Often, secondary and tertiary hypothyroidism is combined into one form, called the secondary or central disease.
The predominant age of hypothyroidism is over 40 years. The predominant gender is female.
The causes of the disease depend on its form.
- attack by its own immune system (autoimmune thyroiditis);
- treatment of diffuse toxic goiter;
- iodine deficiency (in regions with pronounced deficiency);
- congenital abnormalities (most often – the gland underdevelopment).
There are a number of risk factors that contribute to the development of the primary form of the disease. Among them are over 60 years old, female gender, smoking, previous head or neck cancer. Increases the risk of developing the pathology of a similar disease in someone from close relatives.
Secondary and tertiary hypothyroidism can be caused by any of the conditions leading to insufficiency of the pituitary or hypothalamus function (trauma, tumor, radiation, surgery, etc.)
The main signs of hypothyroidism are:
- slow speech and thinking
- constant feeling of cold due to slower metabolism
- puffiness of the face and swelling of the extremities caused by the accumulation of mucous substance in the tissues
- change in voice and hearing impairment due to swelling of the larynx, tongue and middle ear in severe cases
- weight gain, which reflects a decrease in the rate of exchange, but a significant increase does not occur, because the appetite is reduced
- tendency to lower blood pressure
- nausea, flatulence, constipation
- menstrual disorders in women.
Symptoms of latent hypothyroidism have many “masks”.
Deficiency of thyroid hormones, mainly in women, leads to depressed mood, inexplicable longing and even severe depression.
When hypothyroidism decreases cognitive function, memory and attention deteriorate, intelligence decreases (explicitly or hidden).
Insomnia, intermittent sleep, difficulty falling asleep and other sleep disorders, including increased sleepiness, may develop.
With increasing prescription of unrecognized and untreated hypothyroidism, intracranial hypertension syndrome develops. There are frequent, and then constant headaches.
Hidden hypothyroidism often occurs under the guise of cervical or thoracic osteochondrosis.
Symptoms of such hypothyroidism are as follows:
- worried about tingling, burning, goosebumps,
- muscle pain in the upper limbs,
- weakness in the hands.
The most common heart “mask” of hypothyroidism: increased blood cholesterol levels, increased blood pressure.
In women, latent hypothyroidism can manifest as menstrual dysfunction, mastopathy.
Edemas can also be a “mask” of latent hypothyroidism. Swelling of the eyelids or general edema of unclear origin is often the only or leading symptom of this disease.
A significant role in the development of hypothyroidism is played by secondary immunodeficiency, which can develop even with a slight decrease in thyroid function.
Anemia can be a sign of latent hypothyroidism, since thyroid hormones stimulate blood formation.
Separately isolated congenital hypothyroidism. Without medication correction, it leads to severe cretinism in children, the development of secondary pituitary adenoma, effusion in serous cavities, and severe cardiovascular pathologies, which are fatal at an early age.
Diagnosis of hypothyroidism even with a bright clinical picture is impossible without additional laboratory and instrumental studies.
Initially, conduct a hormonal study, which determine the level of TSH. If the indicator is at a normal level or exceeds the 10 mIU / ml mark , no further hormonal testing is indicated. If the TSH value is between 4 and 10 mIU / ml, an additional T4 study is performed.
For the diagnosis of secondary hypothyroidism (central) test is used with thyreiberin .
- a clinical blood test (anemia of the normo – or hypochromic type, B12-deficiency anemia is possible);
- biochemical analysis of blood (increased cholesterol, LDL, triglycerides, creatinine, sodium deficiency, hypo-osmolarity , reduced glomerular filtration, excess enzymes);
- assessment of the level of other hormones (increase in prolactin, decrease in testosterone in men and estradiol in women, the norm of LH and FSH).
- Ultrasound of the thyroid gland will show a decrease in the volume of tissue (less often compensatory hypertrophy occurs), hypoechogenicity.
- You can perform an ECG to determine the pathologies of the cardiovascular system, ultrasound of other organs, x-ray. If a central form of hypothyroidism is suspected, an MRI or CT scan is performed. In the results – an empty Turkish saddle syndrome.
The drug of choice in the treatment of hypothyroidism is levothyroxine sodium.
Treatment is carried out to normalize the level of thyroid stimulating hormone.
For adults, the average dose of levothyroxine sodium (L-thyroxin) is 1.6-1.8 mg / kg body weight per day. In different patients, the daily requirement ranges from 25 to 200 µg / day.
Selection of the dose should be carried out gradually, starting with the minimum. The initial dose does not exceed 25-50 mg / day.
The increase is carried out no earlier than 2 months when the body adapts to the initial dose of the drug. In order to assess the adequacy of the replacement therapy, periodic monitoring of the level of TSH in the blood is necessary.
The body’s need for thyroid hormones in summer is often reduced, which must also be taken into account.
Experience shows that in men the average need for L-thyroxin is slightly higher than in women. It is important to remember that in children the need for the drug is higher than in adults, and in elderly patients, on the contrary, much lower.
It is important to educate patients with hypothyroidism self-control: monitor well-being, pulse, blood pressure, body weight, tolerance of thyroxin, keep a diary of observations. This will help avoid the complications of hypothyroidism and the side effects of the hormones used.
With early treatment, the prognosis is favorable.