ESPE Abstracts (2016) 86 P-P1-925

L-selenomethionine Supplementation in Children and Adolescents with Autoimmune Thyroiditis: Preliminary Results of a Randomized Double-blinded Placebo-controlled Clinical Trial

Ioannis Kyrgios, Aikaterini Dimopoulou, Eleni Kotanidou, Angeliki Kleisarchaki, Konstantina Mouzaki & Assimina Galli-Tsinopoulou

4th Department of Pediatrics, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Papageorgiou General Hospital, Thessaloniki, Greece

Background: It has already been documented that selenium treatment has beneficial effects in adult patients with autoimmune thyroiditis, especially in those with a higher titer of antibodies and increased inflammatory disease activity.

Objective and hypotheses: To investigate whether daily supplementation of organic selenium at a high dose (200 μg in the form of L-selenomethionine) has any effect on the titer of thyroid autoantibodies.

Method: One hundred children and adolescents with a diagnosis of autoimmune thyroiditis were randomized to receive daily either 200 μg of organic selenium (in the form of L-selenomethionine) or placebo for 6 months. In all participants, the levels of fT4, TSH, as well as the titer of TPO and Tg autoantibodies are determined at 3 times (0, 3, 6 months) and ultrasonography of the thyroid gland is performed at 2 times (0, 6 months). Here is presented the analysis of the data obtained from 42 patients that completed 3 months and 23 patients that completed 6 months of treatment.

Results: After a 3-month period, a difference, though not statistically significant, in the change of anti-Tg levels was detected in both groups (decrease in the intervention group vs increase in the control group: Δ:−84.6±72.0 vs +24.3±24.9 IU/ml, P=0.225); after 6 months, a greater decrease in the change of anti-Tg levels was also observed in the intervention group (Δ:−156.8±115.0 vs −59.8±40.8 IU/ml, P=0.592). In contrast, no difference was detected in the change of anti-TPO levels (increase in both groups) either after 3 (P=0.379) or 6 months of treatment (P=0.556).

Conclusion: Based on these preliminary results, selenium supplementation is suggested to decrease the levels of the antibodies against thyroglobulin in children and adolescents with autoimmune thyroiditis. The completion of the study, after the inclusion of all patients and for the whole study period, is needed in order to draw safer conclusions.