Causes of an increase in the thyroid gland

March 28, 2018 15:34 | Diagnostics
The thyroid gland may increase with the following diseases:

Euthyroid struma :
- iodine deficiency;
- medicines, food products;
- violation of iodine utilization;
- pubertal struma.

Hyperthyroid struma :
- inflammation of the thyroid gland;
- thyroid carcinoma.

When the thyroid gland is enlarged to differentiate the struma with eu, hypo- and hyperthyroidism, laboratory studies are needed.

Let us dwell on the above diseases in more detail.

iodine deficiency. The thyroid gland is enlarged already at birth or increases in the first weeks of life;the metabolism is euthyroid. Lack of iodine( insufficient iodine intake, increased need for iodine or increased iodine excretion through the kidneys) may be due to the presence of goitre in the mother. Confirmation: the level of inorganic iodine in the plasma is reduced, the content of protein bound iodine is almost always normal. In some families, there is a constitutionally low need for iodine, therefore, with the same intake of iodine in the body in one family, euthyroid is noted, in another - the hypothyroid struma.

Medicaments, food products .A frequent cause of euthyroid goiter in newborns is the chronic intake of iodine by the mother during pregnancy;in other cases this does not cause an increase in the thyroid gland in the newborn. Thus, it can be considered that special constitutional factors play a role. Some medicines cause goiter. The same action has certain foods: some varieties of cabbage, soy.

Disruption of iodine utilization .If the enlargement of the thyroid gland appears only at the 1st month of life, and sometimes on the 2nd or 3rd year or even later, the cause may be a violation of the synthesis of the hormone( disruption of iodine utilization).Since, as is known, the synthesis and use of a hormone is a complex enzymatic process, the disturbances in this system can be different.

1. Disturbance of iodine accumulation in the thyroid gland can be detected in vivo only by means of radioisotope analysis;while other organs show a normal ability to accumulate iodine).

2. Disturbance of enzymatic oxidation of accumulated iodine and iodination of tyrosine due to a deficiency of peroxidase. In this case, goiter is often combined with deafness or deaf-mute. Heterozygous parents may have hypothyroidism, whereas in homozygous children, euthyroid goiter is observed, or goitre with mild signs of hypothyroidism.

3. Insufficient formation of triiodothyronine and tetraiodothyronine due to a deficiency of an as yet unknown binding enzyme.

4. Violation of deiodination( lack of diiodinase), as a result of which a significant amount of monoiodotyrosine and diiodotyrosine migrates from the thyroid gland and is excreted by the kidneys, instead of serving for the formation of thyroxin.

5. The formation of pathological iodoprotein.

6. Inability of peripheral organs and tissues to be disposed of, already formed thyroxine.

In all cases, monitoring the content of thyroxin, through the hypothalamus and pituitary gland, may be the cause of thyroid hyperplasia. If this stimulation does not compensate for the hereditary deficiency of the enzyme, then a hypothyroid struma is formed. Causes of hyperstimulation may be a deficiency of iodine, a disruption of iodine utilization, as well as various medications.

The pubertary .If the enlargement of the thyroid gland appears in the prepubertal period, then, as a rule, there is a pubertal struma( pubertal baseodism, a teenage stripe) with euthyroid exchange. In these cases, with the help of small doses of thyroxin, central stimulation of the gland can be reduced, which is especially desirable for girls.

Hyperthyroid Extension .The disease can develop in children of any age, but most often during puberty. At the same time, the regulatory mechanism is disrupted to such an extent that an elevated level of hormones does not, as is the case in normal, lead to a drop in iodine metabolism. The effect of a long-acting thyroid stimulant TSDD can be found in cases with hyperthyroidism and ophthalmopathy. Symptoms of hyperthyroid metabolism: hyperkinetic heart syndrome, psychomotor excitability, low need for sleep, moist warm skin, hair loss, shiny eyes, Gref symptom, Moebius symptom( weak convergence), low-grade fever, weight loss with bulimia, accelerated maturation of the skeleton, premature ossificationcranial sutures.

Differential diagnosis of : the clinical symptoms of hyperthyroidism in children present little diagnostic alternatives. The most difficult to distinguish between autonomic lability and hyperthyroidism. Wet cold hands and feet, chilliness, drastically changing blood pressure during the examination and lack of finger tremor are signs of vegetative lability. The child with hyperthyroidism of the limb, although wet, but warm, he does not chill. He often has a "fluctuating goiter", and even with no load( at night), tachycardia and rapid breathing are retained. In the presence of severe symptoms from the cardiovascular system, it is also necessary to exclude increased production of catecholamines( pheochromocytoma).

Symptoms of hyperthyroidism in newborns should be borne in mind that they can be caused by hyperthyroidism in the mother, especially if she had exophthalmos, since the substance that determines exophthalmos can enter the child's body and cause it to have hyperthyroidism with exophthalmos. However, this condition quickly passes without treatment.

Inflammation of the thyroid gland .Edema of the gland due to acute inflammation in children is very rare. In favor of such a diagnosis, inflammatory changes in blood, local soreness and fever testify. Subacute giant cell thyroiditis, which affects mainly women, is observed in children very rarely. It also manifests inflammatory symptoms with distinct localized pains in the gland. Nevertheless, it is difficult to make a differential diagnosis with a tumor. Chronic lymphocytic inflammation of the gland( Hashimoto's string) in children is a rare phenomenon. It can manifest in girls of school age in the form of a painless dense enlargement of the gland. Detection of antibodies to thyroid tissue confirms the diagnosis.

Thyroid carcinoma .Among rare thyroid tumors, carcinoma presents a diagnostic problem due to the lack of local manifestations: poorly palpable, hard small polymorphic nodules in a slightly enlarged or not enlarged gland. The true symptomatology in children is deceptive: an increase in the cervical lymph nodes, a miliary carcinomatosis of the lung, which is often detected by chance or in connection with increasing dyspnea and erroneously treated as lung fibrosis. If you suspect a carcinomatosis, you need an early biopsy and an urgent scintigraphic examination to find cold nodes in the thyroid tissue. Since there are forms of carcinoma that are capable of accumulating iodine, the absence of cold nodes does not exclude the presence of carcinoma. If the picture of the lungs causes suspicion of miliary metastasis, then a primary tumor should be sought.

Women's magazine www. BlackPantera.en: G. Everbeck