The role of thyroid autoantibodies in the etiology of endemic goiter in schoolchildren of Isfahan, Iran.

Background: Eleven years after the initiation of universal salt iodization program in Iran, the prevalence of goiter is still high in some areas. Aim: To investigate the role of thyroid autoimmunity in the etiology of residual goiter in schoolchildren of Isfahan, Iran. Material and methods: In a cross-sectional study, 2331 schoolchildren were selected by multi-stage random cluster sampling. Thyroid size was estimated in each child by inspection and palpation. Urinary iodine concentration (UIC), serum anti-thyroperoxidase antibody (anti-TPO Ab), and anti-thyroglobulin antibody (Anti-Tg Ab) were measured. Results: Overall, 32.9% of children had goiter. The median UIC was 1955.5 μg/dl. There was significant difference in prevalence of positive anti-TPO Ab in goitrous (grade 2) and non-goitrous children (9.7 vs 3.7%, p= 0.02). Goitrous children had higher prevalence of positive anti-Tg Ab than non-goitrous ones (15.1 vs 3.1%, p<0.001). Conclusions: According to the present study, goiter is still a public health problem in this region. This study suggests that thyroid autoimmunity is among the contributors of goiter persistence after elimination of iodine deficiency in Isfahan.