Radiation-induced pathomorphism of endemic goiter in children and adolescents in a focus of iodine deficiency (initial manifestations of remore effects of the Chernobyl accident)

Abstract

The formation of remote consequences of radiation effects on the thyroid status of the population exposed to low-dose radiation was studied. The authors analyzed epidemiological, clinical, biochemical, hormonal, ultrasonographic, immunological, and morphological characteristics of the prevalence and intensity of endemic goiter in children and adolescents living in two iodine-deficient districts of the Oryol region observed after contamination of their territory with 137-Cs in a dose of 1 to 5 Ci/km2 and in-corporation of 131-I in a dose of 20-30 rad and in a control district free from radiation contamination. The results indicate that under the effect of low-dose combined irradiation endemic goiter in the observed districts acquired atypical features in the six years that passed since the Chernobyl accident in comparison with that in the control region: 1) thyromegalia prevalence is increased, its level being disproportionate with the degree of the existent iodine deficiency; 2) sex-specific differences are completely absent; 3) the maximal strain is observed in children exposed to radioactive iodine in utero 4) morphologically, variants of diffuse goiter with a high risk of node formation predominate; 5) progressive growth of thyroid parenchyma is associated with increased thyroglobulin elimination, this increasing the strain of the humoral component of antithyroid autoimmunity. These data indicate that the modifying effect of low-dose exposure on endemic goiter resulted in the disease pathomorphism associated with oncological risk and increased risk of autoimmune thyroiditis.