Chronic thyroiditis in children

To chronic nonspecific thyroiditis are autoimmune and fibrotic. Fibrous thyroiditis almost does not occur in childhood. Autoimmune thyroiditis or chronic thyroiditis is the most common thyroid disorder in children and adolescents.

The disease is determined by the autoimmune mechanism, but the basic immunological defect is unknown. Histologically, lymphocytic infiltration, thyroid tissue hyperplasia, and then atrophy of thyroid cells are detected.

Synonyms

Lymphocytic thyroiditis, Hoshimoto's goiter

ICD-10 code

• E06 Thyroiditis.
• E06.2 Chronic thyroiditis with transient thyrotoxicosis.
• E06.3 Autoimmune thyroiditis.
• E06.5 Other chronic thyroiditis.
• E06.9 Thyroiditis, unspecified.

Epidemiology

Often sick girls after 6 years, the maximum incidence is revealed in adolescents.

[1], [2], [3], [4], [5], [6]

Causes of chronic thyroiditis in children

Chronic lymphocytic thyroiditis is an organ-specific autoimmune disease. In this case, antibodies inhibit the secretion of thyroid hormones and are involved in the destruction of thyroid cells. In the serum, antibodies to thyroperoxidase and thyroglobulin are detected. These antibodies block the addition of iodine to thyroglobulin, have a toxic effect on thyroid cells. There were also detected autoantibodies stimulating the proliferation of thyroid cells.

Disturbance of iodine addition to thyroglobulin leads to inhibition of the synthesis of T3 and T4, which, in turn, stimulates the secretion of TSH. An increase in the level of TSH causes compensatory hyperplasia of the thyroid gland, so patients have an euthyroid state for many months or even years. The goiter in chronic lymphocytic thyroiditis is caused by both hyperplasia and lymphocytic infiltration of the thyroid gland.

[7], [8], [9], [10], [11],

Symptoms of chronic thyroiditis in children

The goiter develops gradually. In most children, iron is increased diffusely, hard to touch and painless. Approximately in 1/3 of cases, the lobularity of the gland is noted, which may appear "knotty." As a rule, patients do not make complaints, the content of hormones is more normal, and sometimes subclinical hypothyroidism (high level of TSH at normal T3 and T4 indices) is revealed in the laboratory. In some cases, lymphocytic thyroiditis may manifest as transient thyrotoxicosis (hashitoxicosis).

The clinical course of autoimmune thyroiditis is highly variable. The goiter can spontaneously decrease and disappear, or for many years the hyperplasia of the thyroid gland with clinical and laboratory euthyroid status is preserved. Quite often after months or years, hypothyroidism develops. Autoimmune thyroiditis is the most common cause of non-frightful juvenile hypothyroidism. Autoimmune thyroiditis is asymptomatic, and many children recover spontaneously.

Diagnosis of chronic thyroiditis in children

It is based on the determination of serum antibodies to microsomal thyroid antigens - the titer of antibodies to microsomal thyreperoxidase is increased. Most patients also show an elevated titer of antibodies to thyroglobulin. As an additional method of research, ultrasound of the thyroid gland is used.

[12], [13], [14], [15], [16], [17]

Differential diagnosis

Differential diagnostics of autoimmune thyroiditis in children is most often performed with juvenile struma, diffuse toxic goiter, subacute thyroiditis, nodular and mixed goiter, thyroid cancer. Subacute thyroiditis develops after viral infections, is prone to wave-like course, ends with complete recovery. Acute purulent thyroiditis in childhood is extremely rare, it usually precedes a respiratory infection or trauma. This is characterized by extreme soreness of the gland, edema, redness and restriction of mobility of the neck, dysphagia.

[18], [19], [20], [21]

Treatment of chronic thyroiditis in children

If the patient has antithyroid autoantibodies against the background of the euthyroid state, treatment with levothyroxine sodium is not necessary, since the drug does not affect the duration and severity of the autoimmune process. The definition of T ₄ and TSH in the blood serum is shown every 6-12 months. With hypothyroidism, "levothyroxine sodium is prescribed to children under the age of 12 for 3-4 μg / kg per day for adolescents - 1-2 μg / kg per day. With latent hypothyroidism (concentration, T ₄ normal, TSH - increased), it is also recommended to prescribe levothyroxine sodium.

Prognosis for chronic thyroiditis in children

Function of the thyroid gland in autoimmune thyroiditis may vary depending on the prevalence of thyroid-stimulating or tyreoblocking autoantibodies. Perhaps spontaneous recovery or, on the contrary, the development of persistent hypothyroidism.