A subacute inflammatory process that develops in the area of the thyroid gland is called subacute thyroiditis. Currently, the exact causes of the development of this disease are still a big question. Most scientists are inclined to believe that this pathology has a viral nature. The role of autoimmune reactions in the occurrence of subacute thyroiditis also cannot be ruled out. From a morphological point of view, this pathological process is characterized by the formation of granulomatous foci with simultaneous destruction of thyrocytes. The duration of subacute thyroiditis averages from two to three months, after which, in most cases, a full recovery occurs. However, sometimes this condition may be complicated by persistent hypothyroidism, heart failure, and so on.
The main difference between subacute thyroiditis and acute inflammatory process with which the thyroid gland is confronted is its longer duration. As for chronic thyroiditis, it is accompanied by much less pronounced clinical manifestations than the subacute form. This disease is also called thyroiditis de Kerven. This name was obtained in honor of the scientist who first described it in nineteen fourth year.
According to statistics, this pathology accounts for from one to five percent among all diseases from thyroid gland. It is noticed that female representatives are almost five times more likely than men to face this pathological process. However, most patients are in the age range of thirty to sixty years. The interrelation of subacute thyroiditis with a viral infection has also been suggested by the fact that a significant increase in the incidence rate is observed in the autumn-winter season, in which outbreaks of acute respiratory viral infections occur. And although we said that most often this disease ends in complete recovery, approximately two percent of the cases are relapses.
Currently, most scientists are of the opinion that such an inflammatory reaction is caused by a viral infection. On average, from the time of SARS to the onset of acute thyroiditis, it takes from three to six weeks. It is noticed that most often the thyroid gland undergoes the development of an inflammatory process after infections localized in the upper respiratory tract. In addition, many authors say that there is a genetic predisposition to the occurrence of this pathology, which is represented by a carrier of a particular gene.
We have already said that during this pathological process granulomatous foci form in the tissues of the gland. The mechanism of development of subacute thyroiditis is presumably represented by the penetration of viral particles into thyrocytes, due to which atypical proteins are being actively produced. These proteins are foreign to the immune system, which contributes to the occurrence of the inflammatory response. The cells of the immune system accumulate in the affected area, followed by the formation of giant cell and epithelioid cell granulomas. Immediately the thyroid gland itself expands, and its follicles rupture, throwing it into the blood thyroid hormones. The depletion of thyroid hormones occurs in a period of one to two months, and then hypothyroidism develops. In the end, marked scarring granulomatous foci and restoration of the functional activity of the affected organ.
During the course of this disease, three successive stages are distinguished: thyrotoxic, euthyroid, and hypothyroid.
Symptoms of subacute thyroiditis
Subacute thyroiditis manifests with general weakness and subfebrile or febrile fever. The earliest symptom is pain localized in the anterior surface of the neck. There is an increase in pain during chewing or swallowing, as well as turning the neck.
At the first stage, symptoms characteristic of hyperthyroidism occur. A sick person complains of emotional lability, fatigue and excessive sweating. There is a gradual weight loss. The patient becomes overly irritable, it is difficult for him to concentrate on one thing. A characteristic point is the complaint of poor tolerance to stuffiness. An examination reveals an acceleration of the heart rate. On average, the duration of this phase is from one to two months.
After this comes the euthyroid stage. It is characterized by the gradual disappearance of the above clinical manifestations. At first glance, the condition of a sick person is normalized, but then symptoms that indicate hypothyroidism join. They are represented by swelling of the face, dry skin, apathy and lethargy, weight gain, decrease in body temperature, and so on. It is worth noting that sometimes this stage passes unnoticed by a sick person, since the gland can quickly compensate for the lack of hormones.
Diagnosis and treatment of the disease
Diagnosis of this disease begins with an objective examination. Laboratory tests include general and biochemical blood tests, assessment of the level of thyroid hormones, as well as an antibody test. An ultrasound examination of the thyroid gland is mandatory. Additionally, scintigraphy and fine-needle biopsy are prescribed, followed by histology of the material obtained.
Treatment of the thyroid gland is carried out using glucocorticosteroids, nonsteroidal anti-inflammatory drugs. After the symptoms of hyperthyroidism have been stopped, replacement therapy with thyroid hormones is prescribed.
Prevention of thyroid disease
For prophylaxis development of subacute thyroiditis should be protected from viral infections. For this purpose, it is recommended to direct your attention to increasing the level of immune defense, avoid contact with sick people and so on.