thyroiditis

Generality

Thyroiditis is a chronic inflammatory process affecting the thyroid; there are different forms, the most common of which, we will deal with in this article, is Hashimoto's thyroiditis . In this disease the butterfly-shaped gland located in the anterior region of the neck - which is precisely the thyroid - is damaged by abnormal antibodies. For this reason the pathology is part of the group of autoimmune thyroiditis.

In response to the aggression of the immune system, thyroid cells develop a chronic inflammatory process, which in many cases leads to a functional reduction of the gland. Not surprisingly, therefore, Hashimoto's thyroiditis is the most common cause of hypothyroidism.

Causes

The reasons why the body's immune system (which normally protects it and helps it fight infections) produces antibodies that attack the thyroid to make it unable to produce sufficient amounts of hormones, have not yet been completely clarified. This aggression seems to have multi-factorial origins and has been related, for example, to hereditary and dietary factors (the sudden increase in iodine intake can aggravate the autoimmune process), with sex (it is more common in women than in men, with a ratio 5-10: 1) and age (it is typical of the second adult age). Furthermore, Hashimoto's thyroiditis is often associated with other autoimmune diseases (celiac disease, type I diabetes, Addison's disease, vitiligo, rheumatoid arthritis, etc.). In the second decade of life it affects about one to two percent of the population, while between fifty and sixty years up to 3-4% of subjects are found.

The term "of Hashimoto" derives from the first Japanese doctor, Dr. Hakaru Hashimoto, who in 1912 described the first case of thyroiditis with leukocyte infiltration, now also known as chronic autoimmune thyroiditis.

Symptoms and complications

To learn more: Symptoms Hashimoto's disease

Chronic lymphocytic thyroiditis (or Hashimoto) can remain asymptomatic for a long time and generally has a subtle beginning. The progression is slow, normally takes several years and in an advanced stage causes irreversible damage to the gland. Thus there is a decrease in thyroid hormones in the bloodstream, accompanied by the onset of the classic symptoms of hypothyroidism.

The clinical manifestations of Hashimoto's thyroiditis vary considerably depending on the stage of the disease and the subsequent severity of hypothyroidism. At first the patient may notice symptoms such as weakness and easy fatigue, which can mistakenly be confused as a sign of the passing years. Later on, the symptoms of Hashimoto's thyroiditis become more debilitating; for example, pale and cold skin, reduced tolerance to low temperatures, constipation, depression, hypercholesterolemia, weight gain mainly due to water retention (the face, in particular, takes on a swollen appearance), hoarse voice, menorrhagia (in woman), muscle-joint pain and stiffness.

The symptomatic variability of Hashimoto's thyroiditis complicates its clinical diagnosis, which is set by simple laboratory tests on a blood sample.

In response to the decrease in blood levels of thyroid hormones, the pituitary (the small unit that regulates the functionality of the endocrine system) tries to compensate for this deficit by stimulating the thyroid to accelerate its activity. To do this, the pituitary gland increases the secretion of TSH (thyroid stimulating hormone), which in the long term causes a compensatory enlargement of the gland. For this reason, Hashimoto's thyroiditis can be accompanied by goiter, a noticeable swelling in the anterior region of the neck caused by increased thyroid volume; in addition to the aesthetic and psychological repercussions, a large goiter can cause respiratory and swallowing problems. Before his appearance, when the disease is still in an early stage, the patient with thyroiditis may therefore feel a sensation of tension in the anterior region of the neck.

Goiter is one of the late complications of Hashimoto's disease and like the other signs that we will see later on, it can be effectively prevented by adequate replacement therapy. Due to the increased levels of LDL cholesterol, a person affected by this disease, which has not been adequately treated, presents a high cardiovascular risk, further increased by a possible cardiomegaly (increase in pathological heart volume). In advanced Hashimoto's disease a severe depression is also common, with a significant drop in libido and mental faculties.

Finally, severe hypothyroidism that has not been adequately treated can lead to myxedema, in which the patient's face (half-open mouth, thick and wrinkled skin, poor hair and eyebrows), his skin (yellowish, thick, pale, cold and dry) and the nails (dry and brittle) take on a characteristic appearance.

During the evolution of thyroiditis there may also be transient periods characterized by hyperthyroidism, that is by an excess of thyroid hormones in the blood, due to the rupture of the follicles damaged by the autoimmune process.