Effat Khorasani, Seyed Reza Mirhafez, Shabnam Niroumand,
Both iodine and selenium are essential important micronutrient required for the synthesis of thyroid hormones. The aims of this study are to assess selenium status in hypothyroid children and to determine its association with thyroid hormones metabolism. This cross-sectional study was conducted using a convenient sample of hypothyroid children attending to children endocrinology clinic between July 2015 and March 2016 in Neyshabur, Iran. Selenium, T4 and TSH in serum of 23 hypothyroid children, 1-72 month of age were measured. SPSS, version 11.5 was used to analyze the data. The Student´s t or the Mann-Whitney U and bivariate and partial correlation tests were used in the analyses. The mean age of the participants was 30 month (±25.09). The mean ± SD of plasma Selenium concentration in hypothyroid children was 98.79 ± 13.63 μg/l. Considering the conventional serum Selenium-deficiency cutoff (<90.0 μg/l), 26.08% of children had low serum selenium. Using the arbitrary level of thyroid hormones for normal thyroid metabolism, 17.39% of the children had elevated TSH level and 4.34% of the children had serum T4 < 4.7 nmol/l. Spearman correlation test showed that selenium level was significantly correlated with TSH (r= 0.63, p =0.001), weight (r= 0.53, p=0.008) and age(r=0.44, p=0.03). In study children, selenium level indicated reverse significant correlation with T4 (r=-.58, p=.004). In the present study, we showed that selenium deficiency plays a role in circulating thyroid hormones concentration and also affect the necessary levothyroxine dose required for hypothyroid children. These findings call for an increased attention to serum selenium levels in hypothyroid children. Selenium supplementation may be useful in hypothyroid treatment.