Background The problem of iodine deficiency diseases (IDD) is relevant in connection with the significant occurrence of iodine deficiency among the population of many countries of the world, an increase in morbidity with a wide range of clinical manifestations and a marked tendency to increase the incidence and severity among children of all age groups.

Material and methods The research was conducted on the basis of the data of the preventive survey (187 children) living in the ecologically dependent biogeochemical endemic zone with iodine deficiency in the mountain region of the Transcarpathian region in the period of 2014–2015y.y.

Result Taking into account the morphometric characteristics of the thyroid gland in the chidren was found a slight difference between the standard values of unchanged parenchyma thyroid gland, the size of the gland was on 24.4% lower than the reference in the girls and on 27.5% in the boys in the patients with hypoplasia., The size of the thyroid gland of children with the hyperplasia was higher than the reference on 39.04%in the girls and on 31.8% in the boys. The data of the state of the thyroid system testify have differences in the levels of TSH - from 2.87 ± 0.67 mO/l to 1.89 ± 0.43 mO/l, p = 1.97 × 10–8, respectively, in groups in children with hyperplasia of the thyroid gland and with normal thyroid parenchyma. The levels of AT-TG are higher than the reference in children with thyroid hyperplasia and within the normal range in children with normal thyroid gland parenchyma, which suggests insignificant effects on the interference with the physiological process of T3 and T4 synthesis . The value of AT-TPO varied within the norm with a prevalence of in the normal thyroid parenchyma children group and indicated the potential threat of thyroid pathology developing in this group and violation of the processes of iodine oxidation. The values of TCG, T3 in both groups tended to be lower bound when the level T4 corresponded to the upper value of the reference values. The minimum thyroid deficiency was observed in the children thyroid gland hyperplasia, in particular, the TSH level ranged from 2.5 to 4.0MU/l, the TTG/fT4 index ranged from 0.19 to 0.29.

Conclusion Recommended the appointment of correction with iodine-selenium supplementation in the children with thyroid gland morphometric changes, which identified risk factors on endemic goiter and minimal thyroid failure