Is iron deficiency responsible for endemic goiter in semirom?

In spite of iodine fortification programs, goiter is still hyperendemic in Semirom, a mountainous region in the central part of Iran. This study was conducted to assess whether iron deficiency could be responsible for the high prevalence of goiter in this region. A total of 1828 schoolchildren, aged 7-13 years, were evaluated for presence of goiter, and 220 cases were randomly selected. Urine and serum samples were collected from these children and assayed for urinary iodine concentraton [UIC] and serum ferritin, iron, thyroxine [T4] and thyroid stimulating hormone [TSH] concentrations. In the 1828 children evaluated, 670 cases [36.7%] were goitrous, with goiters of grade 1 or 2. The mean UIC in children was 19.3 +/- 9.1 micro g/dl. Mild [UIC <10 micro g/dl] and moderate [UIC <5 micro g/dl] iodine deficiency was detected in 6.4% and 3.2% of cases, respectively. Only 1.8% of children were severly iodine deficient [UIC <2 micro g/dl]. The median serum ferritin concentration was 26.6 ng/ml [95% CI: 24.2-28.9], and 11 cases [5%] had serum ferritin concentrations less than 20 ng/ml. Goiter rate was 48.3% and 50.3% in children with low and normal serum ferritin levels, respectively [P = NS]. It seems that factors other than iodine and iron deficiency may, at least partly, be responsible for the high prevalence of goiter in the area studied. Further investigations for evaluating other micronutrient deficiencies and autoimmunity in goitrous children would contribute to the planning more effective goiter control programs

[ Prevalence of clinical goiter and urinary iodine concentration in 8-12 years old students of Semirom in 2004 [15 years after execution of national program for elimination of iodine deficiency disorders]]

With respect to the high prevalence of goiter in Semirom before the initiation of National Program for Elimination of Iodine Deficiency Disorders [NPEIDD], the impact of the program on the prevalence of goiter in 8-12 years old students of Semirom was investigated in this study, after 15 years of sucessful execution of NPEIDD. After excluding students with any clinical evidence of hyper- or hypo-thyroidism, 1817 students aged 8-12 years were recruited based on a cluster sampling method. The participants were examined for the presence of goiter by experiencd endocrinologists. Urinary iodine was measured in 182 examined students, too. Chi- Square statistical method was used to analyze the data. Goiter was detected in 36.7% of the students [grade 1: 30.4%, grade 2: 6.3%]. The median urinary iodine was 18.5 and mean was 19.37 +/- 9.22 ?g/dl in collected specimens. The adequacy of urinary iodine in students of Semirom confirms the success of NPEIDD, however, the higher than expected prevalence of goiter in the region suggests the probable role of other goitrogenous or autoimmune factors. Further studies should be performed to investigate the possible causes