title: High prevalence of goiter in an iodine replete area: do thyroid auto-antibodies play a role?
abstract: BACKGROUND
  Despite long standing iodine supplementation in Iran the prevalence of goiter remains high in some areas. This may suggest that causes other than iodine deficiency, such as autoimmune thyroid diseases, should also be considered. We therefore assessed the prevalence of anti-thyroid antibodies in children living in an inland area in Iran and correlated these findings with prevalence of goiter within this region.
  
  
  METHODS
  In a cross-sectional study, 1948 students were selected by multistage random cluster sampling from the 108 primary schools (age, 7-13 year-old) of the urban and rural areas of Semirom. After obtaining written consent from their parents, the children were examined by endocrinologists for goiter grading. Grade 2 goitrous children (108 cases) were compared with non-goitrous children (111 children as control group) for anti-thyroid antibodies.
  
  
  RESULTS
  Overall, 36.7% of 1948 students had goiter. The mean urinary iodine excretion level was 1.49+/-0.7 micromol/L. This was within normal limits. Of 219 children studied, 4.3% presented with subclinical hypothyroidism, and 7.3% had positive anti-thyroid antibodies. There was non-significant difference of positive thyroperoxidase antibody (anti-TPO) (Odds Ratio= 3.2, p= 0.13) but significant difference of anti Tg between goitrous and non goitrous children (Odds Ratio: 5.6, 95% CI: 1.18-26.0, p: 0.015).
  
  
  CONCLUSIONS
  This study suggests that autoimmunity may be one of the mechanisms responsible for goiter persistence after iodine replenishment in this iodine deficient region, but the role of other factors should also be considered.
authors: Assistant Professor of Endocrinology, Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors: Mahin
authors: M
authors: Hashemipour
authors: Masoud
authors: M
authors: Amini
authors: Ashraf
authors: A
authors: Aminorroaya
authors: Mansour Iavash
authors: MI
authors: Dastjerdi
authors: Hassan
authors: H
authors: Rezvanian
authors: Ali
authors: A
authors: Kachoei
authors: Mohammad Hassan
authors: MH
authors: Moaddab
authors: Mohammad
authors: M
authors: Mohammadi
authors: Roya
authors: R
authors: Kelishadi
authors: Zhale
authors: Z
authors: Amini
authors: Sassan
authors: S
authors: Haghighi
authors: Fariba
authors: F
authors: Shojaee-Moradie
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D016022:Case-Control Studies; D002648:Child; D016000:Cluster Analysis; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D006042:Goiter / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007453:Iodide Peroxidase / Q000378:metabolism; D007455:Iodine / Q000008:administration & dosage* / Q000172:deficiency / Q000652:urine; D007492:Iran / Q000453:epidemiology; D008297:Male; D016017:Odds Ratio; D015995:Prevalence; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage; D013967:Thyroiditis, Autoimmune / Q000453:epidemiology*
chemical_list: D001323:Autoantibodies; D017673:Sodium Chloride, Dietary; C034024:iodized salt; D007455:Iodine; D007453:Iodide Peroxidase