Introduction of iodized salt to severely iodine-deficient children does not provoke thyroid autoimmunity: a one-year prospective trial in northern Morocco.

To determine if introduction of iodized salt induces thyroid autoimmunity in goitrous children, we conducted a prospective trial in iodine-deficient Moroccan schoolchildren (n = 323). Local salt was iodized at 25 microg iodine per gram of salt and distributed to households. Before introduction of iodized salt and at 10, 20, 40, and 52 weeks, we measured antithyroid peroxidase antibodies (TPO-Ab), antithyroglobulin antibodies (Tg-Ab), urinary iodine (UI), and thyroid hormones, and examined the thyroid using ultrasound. At baseline, median UI was 17 microg/L and the prevalence of goiter and hypothyroidism was 72% and 18%, respectively. Provision of iodized salt maintained median UI at 150-200 microg/L for the year (p < 0.0001). There was a significant increase in mean total thyroxine (T(4)) and a significant reduction in the prevalence of hypothyroidism (p < 0.001). There was a transient increase in the prevalence of detectable antibodies after introduction of iodized salt (p < 0.0001) with levels returning to baseline at 1 year. Only congruent with 1% of children had elevated TPO-Ab and none had elevated Tg-Ab over the course of the study, and no child with elevated TPO-Ab had abnormal thyrotropin (TSH) or T(4) concentrations. None developed clinical or ultrasonographic evidence of thyroid autoimmune disease and/or iodine-induced hypothyroidism or hyperthyroidism. Rapid introduction of iodized salt does not provoke significant thyroid autoimmunity in severely iodine-deficient children followed for 1 year.     

Role of autoimmune and familial factors in goiter prevalence. Studies performed in a moderately endemic area

The goitrogenic role of autoimmune phenomena in endemic goiter is still uncertain. Scanty and discrepant results have been reported in different areas of the world. This prompted us to evaluate the prevalence of circulating thyroid antibodies in an area of North-Western Tuscany during a survey for endemic goiter. The survey was carried out according to the P.A.H.O. criteria in a stable community. In all schoolchildren (n = 142, age range 7-15 yr) and in most of their parents (n = 159), thyroid size was evaluated and urine was collected for iodine determination. Blood was drawn for determination of circulating thyroid microsomal (MAb) and thyroglobulin antibodies (TgAb), TT3, TT4 and TSH. Prevalence of goiter in schoolchildren was 77.9% and 94.8% in their parents. Mean (+/- SD) urinary iodine excretion was 55.0 +/- 2.1 micrograms/24 h. The overall frequency of TgAb and MAb in the adult population was 14.4%, statistically higher than that of control subjects matched for sex and age. The frequency in schoolchildren was 4.3%. The presence of goiter in children was unrelated to the presence of thyroid antibodies in parents, whether goitrous or nongoitrous. A higher prevalence of goiter was found in children with goitrous parents as compared to children with nongoitrous parents (p less than 0.005). In conclusion, the frequency of thyroid autoantibodies in the adult population of the endemic area studied was increased, but showed no relation with the presence of goiter. The prevalence of goiter in children was associated with the presence of goiter but not of thyroid autoantibodies in parents. These data suggest that autoimmune phenomena are of limited importance in the development of endemic goiter.     

High prevalence of autoimmune thyroiditis in schoolchildren after elimination of iodine deficiency in northwestern Greece.

The current iodine status and the impact of silent iodine prophylaxis on the prevalence of autoimmune thyroiditis among schoolchildren in a formerly iodine-deficient community in northwestern Greece, were investigated. The findings were compared to those obtained from a similar survey conducted 7 years previously in the same area. A total of 302 schoolchildren (12-18 years of age) from a mountainous area of northwestern Greece were examined for the presence of goiter, and blood and urine samples were collected for assessment of thyroid function, antithyroid antibodies and urinary iodine excretion. In those children (n = 42) with palpable goiter or positive antibodies and/or a thyrotropin (TSH) level greater than 5 mU/L, thyroid ultrasonography was performed to estimate thyroid gland size and morphology. Median urinary iodine concentration in the children was 20.21 microg/dL, indicating sufficient iodine intake. Thyroid function was normal in all but 7 children, who had subclinical hypothyroidism (2.5%). Antithyroid antibodies (antithyroid peroxidase [TPO] and/or antithyroglobulin [Tg]) were positive in 32 children, including those with subclinical hypothyroidism (10.6%). Twenty-nine of these children (9.6%) also had the characteristic echo pattern of thyroiditis on ultrasound and were diagnosed to have autoimmune thyroiditis. In comparison to data from our previous survey 7 years ago, there has been a threefold increase in the prevalence of autoimmune thyroiditis among schoolchildren. In conclusion, silent iodine prophylaxis has resulted in the elimination of iodine deficiency in Greece, and this has been accompanied by an increase in the prevalence of autoimmune thyroiditis.     

Hashimoto's thyroiditis: countrywide screening of goitrous healthy young girls in postiodization phase in India

Countrywide salt iodization, to prevent nutritional iodine deficiency, has been achieved in India recently. The current study was planned to evaluate the prevalence of goiter and thyroid autoimmunity and assess thyroid functional status in a cohort of 6283 healthy schoolgirls from different parts of the country in the postiodization phase. Goitrous girls (n = 1810; 28% of subjects) were investigated for serum T4 and TSH, antithyroid microsomal antibody (TMA) and antithyroglobulin antibody (TGA), urinary iodine excretion, and cytomorphology by fine-needle aspiration cytology (FNAC). FNAC carried out successfully in 764 goitrous girls revealed juvenile autoimmune thyroiditis (JAT) in 58 (7.5%), which included Hashimoto's thyroiditis in 43 (5.6%) and focal lymphocytic thyroiditis in 15 (1.9%). TMA and TGA estimated in 722 goitrous girls detected significantly positive titers of TMA (> or =1:1600) and TGA (> or =1:160) in 52 (7.2%) and 4 (0.55%) girls, respectively. Only 29 (67.4%) girls with Hashimoto's thyroiditis were TMA positive. In patients with FNAC-proven JAT, overt clinical and biochemical hypothyroidism was seen in three (6.5%) and subclinical hypothyroidism in seven (15%). Subclinical hyperthyroidism was detected in 5.1% cases of JAT, and none had overt hyperthyroidism. No definite correlation was seen between urinary iodine excretion and thyroid autoimmunity.     

Thyroid autoimmunity is associated with higher urinary iodine concentrations in an iodine-deficient area of Northwestern Greece.

Northwestern Greece was identified in the 1960s for its high prevalence of endemic goiter and iodine deficiency. Although iodized salt has been commercially available since then, a recent epidemiological survey of 3916 schoolchildren found that low-grade goiter is still prevalent in endemic proportions (21%). The aim of this study was to further assess the cause of goiter and the severity of iodine deficiency in children from this endemic area of Greece. Of the 800 children with clinically detectable goiter, 97 children (60 girls and 37 boys, 8-15 years) were recruited for determination of urinary iodine excretion, as well as assessment of thyroid volume and function and detection of antithyroid antibodies. The median urinary iodine concentration was 8.4 microg/dL, indicative of a mild iodine deficiency. Thyroid function was normal in all but 11 children who had subclinical hypothyroidism. Sixteen children (16.5%), including all those with subclinical hypothyroidism, were positive for antithyroid antibodies. Their median urinary iodine concentration (20.6 microg/dL) was higher compared to children who were negative for antibodies (7.4 microg/dL; p<0.001). The mean thyroid volume by ultrasonography (12.2+/-4.1 mL) was above the upper limit of normal for this age group. Thyroid volume was inversely related to the urinary iodine content in the children with negative antithyroid antibodies. Iodine deficiency is still prevalent in northwestern Greece although of mild severity and constitutes the primary cause of goiter among schoolchildren. However, it appears that autoimmune thyroiditis is emerging as a frequent cause of goiter in those children with sufficient iodine intake.     

Prevalence of goiter among schoolchildren from Gorgan, Iran, a decade after national iodine supplementation: association with age, gender, and thyroperoxidase antibodies

BACKGROUND: One decade after universal salt iodization in Iran, goiter prevalence, urinary iodine concentration (UIC) and thyroperoxidase antibody (TPOAb) values were assessed among schoolchildren in Gorgan, Iran. METHODS: From 2003-2004, 500 girls and 900 boys aged 7-11 yr were evaluated for goiter by palpation. UIC was measured in 183 randomly-selected goitrous children. Serum TSH, T4, and TPOAb were measured in 53 goitrous and 30 non-goitrous children with adequate UIC. RESULTS: Goiter was detected in 370 (26.4%) children. Goiter was present in 31% of girls and 17% of boys age 9 (p<0.012); 37% of girls and 20% of boys age 10 (p<0.003); and 52% of girls and 19% of boys age 11 (p<0.0001). Median (range) UIC for all goitrous children sampled was 190 (20-600) microg/l; 220 (30590) in boys and 170 (20-600) in girls (p=0.001). Eight point seven percent of goitrous children and 22% of goitrous girls aged 10-11 had UIC<100 microg/l, while 47% of the goitrous children had UIC> or =200 microg/ l. TPOAb was present in 52.8% of goitrous children and 10% of non-goitrous children (p=0.0001). TPOAb was present in 53.9% of 10-11 and 22.7% of 7-9 yr old goitrous and non-goitrous children (p=0.003) with adequate UIC. Median (range) TSH was 2.9 (0.3-10.9) mlU/I in TPO-positive and 1.8 (0.5-4.1) in TPO-negative children (p=0.001). CONCLUSIONS: Gorgan, Iran, is an iodine-sufficient area and almost half of schoolchildren have more than adequate UIC. TPOAb is associated with endemic goiter. Despite sufficient UIC overall, some school-aged girls remain at risk of iodine deficiency.     

Residual goitre in the postiodization phase: iodine status, thiocyanate exposure and autoimmunity

OBJECTIVE: This study was done to assess goitre prevalence, thyroid functional status and cause of residual goitre among school children in the postsalt iodization phase in India. DESIGN: A cross-sectional study in which, 14762 school children in the age group of 6-18 years, from different States and Union territories of India, were evaluated for goitre prevalence, urinary iodine and thiocyanate excretion, functional status of the thyroid as well as serological and cytopathological markers for thyroid autoimmunity. MEASUREMENTS: Urinary iodine (wet ashing method), urinary thiocyanate (colourimetric method), serum thyroxine [in-house radioimmunoassay (RIA)], serum TSH (IRMA), antithyroid microsomal and antithyroglobulin antibodies (haemagglutination method) were estimated. Fine-needle aspiration cytology was performed in all goitrous subjects giving consent. RESULTS: The overall goitre prevalence was 23% (27.1% girls; 17.8% boys, P < 0.001). Subjects belonging to poor socio-economic strata had significantly higher goitre prevalence. Median urinary iodine excretion (UIE) in goitrous subjects (2-53 micromol/l) was significantly higher than in controls (2-24 micromol/l; P < 0.001). Levels of UIE observed among goitrous subjects showed no relationship with the presence or absence of thyroid dysfunction or with thyroid antibody status. High titres (> or = 1:1600) of TMA were present more often in goitrous subjects (6.08%) than nongoitrous controls (0.34%; P < 0.001) and in girls (7.3%) than boys (2.35%; P < 0.001). TMA positivity were significantly more among goitrous subjects with thyroid dysfunction than in euthyroid subjects. Significantly higher median urinary thiocyanate (USCN) excretion was observed in goitrous subjects (0.75 mg/dl) compared to controls (0.64 mg/dl; P < 0.001) and goitrous girls compared to goitrous boys. USCN excretion of goitrous subjects and controls showed no relationship with functional or thyroid antibody status in various groups. CONCLUSIONS: Persistent, albeit reduced prevalence of goitre, despite adequate iodine prophylaxis, suggests existence of additional factors in goitrogenesis in India. Thyroid autoimmunity can explain only a part of the goitre prevalence. The role of goitrogens in residual goitre prevalence is brought forth.     

Iron supplementation in goitrous, iron-deficient children improves their response to oral iodized oil

OBJECTIVE: In developing countries, many children are at high risk for both goiter and iron-deficiency anemia. Because iron deficiency may impair thyroid metabolism, the aim of this study was to determine if iron supplementation improves the response to oral iodine in goitrous, iron-deficient anemic children. DESIGN: A trial of oral iodized oil followed by oral iron supplementation in an area of endemic goiter in the western Ivory Coast. METHODS: Goitrous, iodine-deficient children (aged 6-12 years; n=109) were divided into two groups: Group 1 consisted of goitrous children who were not anemic; Group 2 consisted of goitrous children who were iron-deficient anemic. Both groups were given 200mg oral iodine as iodized oil. Thyroid gland volume using ultrasound, urinary iodine concentration (UI), serum thyroxine (T(4)) and whole blood TSH were measured at baseline, and at 1, 5, 10, 15 and 30 weeks post intervention. Beginning at 30 weeks, the anemic group was given 60mg oral iron as ferrous sulfate four times/week for 12 weeks. At 50 and 65 weeks after oral iodine (8 and 23 weeks after completing iron supplementation), UI, TSH, T(4) and thyroid volume were remeasured. RESULTS: The prevalence of goiter at 30 weeks after oral iodine in Groups 1 and 2 was 12% and 64% respectively. Mean percent change in thyroid volume compared with baseline at 30 weeks in Groups 1 and 2 was -45.1% and -21.8% respectively (P<0.001 between groups). After iron supplementation in Group 2, there was a further decrease in mean thyroid volume from baseline in the anemic children (-34.8% and -38.4% at 50 and 65 weeks) and goiter prevalence fell to 31% and 20% at 50 and 65 weeks. CONCLUSION: Iron supplementation may improve the efficacy of oral iodized oil in goitrous children with iron-deficiency anemia.     

Iodine supplementation in Austria: methods and results.

Until 1963 Austria was an extremely iodine-deficient area with low iodine intake and high goiter prevalence. Therefore, for the first time in 1963, salt iodination with 10 mg of potassium iodide per kilogram of salt was introduced by federal law. Twenty years after this salt iodination, however, investigations in schoolchildren demonstrated iodine deficiency grade I to II according to the World Health Organization (WHO) (urinary iodine excretion, 42-75 microg/g Crea) and goiter prevalence of far more than 10%. In 1990, salt iodination was increased to 20 mg of potassium iodide per kilogram of salt. In 1994, further investigations in schoolchildren demonstrated an increase of urinary iodine excretion (121 microg/g Crea) and a reduction of goiter prevalence below 5%, with the exception of pupils ages 14-19 (12%). In the year 2000, 10 years after the increase of salt iodination in Austria, 430 nonselected adult inhabitants of three communities in Carinthia (a county of Austria) were investigated for iodine excretion, goiter prevalence, and prevalence of thyroid autoantibodies. This study demonstrated that although iodine supply is sufficient now in Austria (males, 163.7 microg of Crea; females, 183.3 microg of iodine per gram of Crea), goiter prevalence is still high in the elderly, who lived for a longer period of iodine deficiency (34.3% in women and 21.3% in men), whereas goiter prevalence in younger people up to age 40 years is below 5%. It could also be shown that the percentage of thyroid autoantibodies is now as high as in other countries with sufficient iodine supply (3.19% in males, 5.17% in females). In addition to the changes of urinary iodine excretion and goiter prevalence because of salt iodination, changes of incidence in hyperthyroidism and histologic types of thyroid cancer are discussed in this paper. In conclusion, the introduction of salt iodination led to an improvement in iodine supply with a marked reduction of goiter prevalence in people who were born after 1963, but also to an increase in hyperthyroidism and autoimmune thyroid diseases as well as changes in histologic types of thyroid cancer.     

Study of an endemic goiter area in northern Campania.

The purpose of this paper was the determination, in the endemic goiter area of Teano (Caserta, Italy), of: i) The goiter prevalence in a group of 920 patients who attended the Outpatient Endocrinology Department; ii) The urinary iodine excretion in 150 adults (20-73-year-old) and 502 children (10-16-year-old; iii) The thyroid size in the 502 children; iv) The environmental iodine levels. Out of 920 patients a total of 750 (81.5%) goiters were detected. Out of these 750 cases, 415 (55.3%) were of grades 1b and 2, 335 (44.7%) of grades 3 and 4. A statistically significant association between goiter size and age was found (p less than 0.05). Laboratory data were entirely available for 506 goitrous patients. Serum TG levels was increased with goiter size and age, whereas there was a progressive decrease in mean serum TSH levels with increasing goiter size and age. The screening program performed on 502 schoolchildren aged 10 to 16 yr found a 68.3% prevalence of grade 1 goiter and a mean urinary ratio iodine/creatinine of 52 +/- 32 (SD) micrograms/g. A mean urinary ratio iodine/creatinine of 60 +/- 27 (SD) micrograms/g was reported in a sample of 150 adult inhabitants. Iodine measurements in water supplies showed levels equal to or less than 1 microgram/l. The area investigated can be identified as a moderate iodine deficient area and classified as grade 1-2 according to the Pan American Health Organization criteria.     

The predominant form of non-toxic goiter in Greece is now autoimmune thyroiditis.

Endemic non-toxic goiter (NTG) in Greece has been attributed primarily to iodine deficiency. Thirty years ago about 60% of the prepubertal boys and girls examined in endemic goiter regions presented with NTG and among them thyroid autoimmunity was rarely detected. Although iodine supplementation has corrected this deficiency during the past 30 years, new cases of NTG still appear. To evaluate the prevalence and type of NTG and the effect of iodine supplementation on them in Greece at present, we performed two cross-sectional clinical studies and a retrospective pathology one: (i) thyroid gland volume and urinary iodine excretion (UIE) were assessed in a representative sample of 1213 schoolchildren from previously endemic and non-endemic regions; (ii) serum thyroxine, tri-iodothyronine, TSH, thyroid autoantibodies (AAB) (anti-thyroid peroxidase and anti-thyroglobulin antibodies) and UIE (in 60 patients) were measured in 300 consecutive patients with NTG from Athens and Heraklion; and (iii) we compared the prevalence of autoimmunity among fine needle aspiration smears of benign thyroid pathologies performed by the same pathologist between 1985 and 1986 (975 cases) and between 1994 and 1995 (2702 cases). We found that 12. 5% of the schoolchildren examined in regions with a previous history of endemic goiter had NTG, whereas this percentage was only 1.7% in areas without such a history. In Athens (61.6%) and Heraklion (58. 5%) a substantial number of NTG patients were AAB positive and biochemically hypothyroid. UIE in Athens did not differ between patients with autoimmune goiter (ATG) and simple goiter. The prevalence of autoimmune stigmata in pathology smears has increased from 5.94% (years 1985-1986) to 13.91% (years 1994-1995) (P<0.05). We conclude that: (i) the persistence of endemic goiter in regional foci despite iodine deficiency correction suggests a possible role for a naturally occurring goitrogen; (ii) ATG is the predominant form of NTG in Greece nowadays; and (iii) the five-fold decrease in the prevalence of NTG during the past 30 years followed by the increase of ATG may support the relative character of the latter.     

Goiter persistence after iodine replenishment, the potential role of selenium deficiency in goitrous schoolchildren of Semirom, Iran.

BACKGROUND: Despite long-standing iodine supplementation in Iran, the prevalence of goiter remains high in some areas. This suggests other nutritional deficiencies may be considered as responsible factors of goiter persistence. Therefore, we assessed the prevalence of selenium deficiency in children living in a mountainous area in Iran to evaluate its correlation with goiter. METHODS: In this cross-sectional study, 1828 students from the 108 primary schools of urban and rural areas of Semirom in central Iran were selected by multistage random cluster sampling. After obtaining written consent from their parents, the children were examined for goiter grading. Grade 2 goitrous children (108 cases) were compared with non-goitrous children (111 children) as control group for serum selenium concentration. RESULTS: Overall, 36.7% of 1828 students had goiter. The mean and median urinary iodine excretion level was 19.3 and 18.5 mug/dl respectively. This was within normal limits. Of 219 evaluated cases, 109 children had selenium deficiency. Mean serum levels of selenium in the goitrous and control groups were 62.7 mug/l and 60.8 mug/l, respectively (p=0.42). There was a borderline significant difference of the goiter prevalence in selenium deficient and selenium sufficient subjects (40.8% vs. 54.3%, p=0.037).Twelve children had clinical or subclinical hypothyroidism. The mean (SD) serum selenium concentration of euthyroid and hypothyroid students were 61.9 (17.2) mug/l and 66.4 (11.9) mug/l respectively (p=0.35). CONCLUSION: In the area studied, selenium deficiency cannot explain high prevalence of goiter and other responsible factors should be investigated. Selenium deficiency may also have mild borderline significant protective effects on thyroid function and goiter.     

Thyroid ultrasound is the best prevalence indicator for assessment of iodine deficiency disorders: a study in rural/tribal schoolchildren from Gujarat (Western India)

OBJECTIVES: (i) To assess the severity of iodine deficiency disorders (IDD), (ii) to determine the aetiology of IDD in Gujarat, (iii) to identify the best prevalence indicator of IDD, and (iv) to compare thyroid volume (TV) results with the WHO International reference. METHODS: Five hundred and thirty schoolchildren (6-15 years) were studied from two districts (Baroda and Dang) and data were collected on dietary habits and parameters such as height, weight, thyroid size by palpation and ultrasonography, urinary iodine (UI), and blood thyroid stimulating hormone (TSH). Drinking water was analyzed for iodine content and food articles for goitrogens. RESULTS: In Gujarat children median UI (interquartile range)=56 (30-96)microg/l, mean TSH=1.71 +/- 2.10mU/l, goiter by palpatio n = 30%, and median TV = 27.8 (23-35)ml. Females had lower median UI (48 (27-82) microg/l) and higher mean TSH levels (2.0 +/- 2.5mU/l) than males. Applying the WHO ultrasonography reference to Gujarat children resulted in an enlarged TV-for-body surface area in almost 100% of subjects. Ninety-nine percent of females and 95% of males had enlarged TV-for-age. Three to eight times larger TV were seen in all subjects as compared with European children. Dang children were severely malnourished. Flavonoids like vitexin, glucosyl vitexin and apigenin were detected in pearl millet. Apigenin was never identified in pearl millet. Dang district water was lacking in iodine content. CONCLUSIONS: IDD is a severe public health problem in Gujarat. Baroda district is a new pocket of IDD. High amounts of dietary flavonoids in Baroda and Dang districts, and lack of iodine in Dang water, account for IDD. TV measurement by ultrasound is the best prevalence indicator of IDD.     

Pregnancy in patients with mild thyroid abnormalities: maternal and neonatal repercussions

A prospective study was undertaken during pregnancy in 120 euthyroid women presenting with mild thyroid abnormalities (TA): 11 with a past history of thyroid disorder, 44 with goiter, 20 with nodules, and 45 with thyroid autoantibodies. The aims of the study were to assess whether the pattern of thyroid alterations during gestation was different in women with TA compared to that in healthy control pregnant subjects and to evaluate possible obstetrical and neonatal repercussions. The overall prevalence of underlying subtle thyroid abnormalities in the cohort was 17%, probably as the result of the environmental moderately low iodine intake. Despite the intrinsic heterogeneity of the four groups of women with TA, the adaptation of the thyroid to the stress of pregnancy was different from that of the control subjects. Noteworthy were 1) the marked elevation of serum thyroglobulin in women with past history of thyroid disorder, goiter and thyroid nodules; 2) the increase in goiter size in a third of the goitrous women, associated with biochemical evidence of functional stimulation of the gland; 3) the indirect evidence of partial thyroidal autonomy in goitrous patients; and 4) the increase in the number and size of thyroid nodules during gestation. Taken together, the data indicated that pregnancy was associated with a greater thyroidal risk in patients with TA compared to healthy subjects. In relation to thyroid autoimmunity, most patients remained euthyroid during gestation, but in a few cases, TSH was elevated at delivery, suggesting diminished thyroidal reserve. Also, 40% of newborns from mothers with thyroid autoimmunity had elevated thyroid peroxidase antibody titers at birth, and there was a highly significant correlation between maternal and neonatal thyroid peroxidase antibody titers. Finally, thyroid autoimmunity was clearly associated with an increased risk of spontaneous abortion (13.3 vs. 3.3%; P less than 0.001). Thyroid function in newborns from mothers with TA was normal and not different from that in controls; similarly, obstetrical features were similar in patients with TA and control subjects. In conclusion, pregnancy is associated with a greater thyroidal risk in women with TA, thereby emphasizing a potential link between pregnancy and thyroid disorders. It is recommended that patients with known, even subtle, thyroid abnormalities be closely monitored during pregnancy, in particular those with a goiter, nodules, or thyroid autoimmunity, especially in areas with a moderately low iodine intake, where the prevalence of mild thyroid disturbances is high.     

Addition of microencapsulated iron to iodized salt improves the efficacy of iodine in goitrous,iron-deficient children: a randomized,double-blind,controlled trial

OBJECTIVE: In many developing countries, children are at high risk for both goiter and anemia. Iron (Fe) deficiency adversely effects thyroid metabolism and reduces efficacy of iodine prophylaxis in areas of endemic goiter. The study aim was to determine if co-fortification of iodized salt with Fe would improve efficacy of the iodine in goitrous children with a high prevalence of anemia. DESIGN AND METHODS: In a 9-month, randomized, double-blind trial, 6-15 year-old children (n=377) were given iodized salt (25 microg iodine/g salt) or dual-fortified salt with iodine (25 microg iodine/g salt) and Fe (1 mg Fe/g salt, as ferrous sulfate microencapsulated with partially hydrogenated vegetable oil). RESULTS: In the dual-fortified salt group, hemoglobin and Fe status improved significantly compared with the iodized salt group (P<0.05). At 40 weeks, the mean decrease in thyroid volume measured by ultrasound in the dual-fortified salt group (-38%) was twice that of the iodized salt group (-18%) (P<0.01). Compared with the iodized salt group, serum thyroxine was significantly increased (P<0.05) and the prevalence of hypothyroidism and goiter decreased (P<0.01) in the dual-fortified salt group. CONCLUSION: Addition of encapsulated Fe to iodized salt improves the efficacy of iodine in goitrous children with a high prevalence of anemia.     

Epidemiological survey of thyroid volume and iodine intake in schoolchildren,postpartum women and neonates living in Ulaan Baatar

OBJECTIVE: Although endemic goiter had been recognized in most parts of the country, there are few available data on iodine-deficiency disorders (IDDs) in Mongolia. This study aimed to characterize the current status of iodine deficiency in Ulaan Baatar, Mongolia's capital city. DESIGN: Cross-sectional, observational study designed and performed according to the surveillance methods for IDD prevalence recommended by WHO/UNICEF/ICCIDD. SUBJECTS: A total of 505 schoolchildren aged 9-14 years (237 girls and 268 boys) and 138 mothers and their neonatal infants were selected to clinical and biochemical examination of the thyroid in 1996 and 1999. MEASUREMENTS: The anthropometric measurements, thyroid volume determined by ultrasound, blood TSH and FT4 concentrations, urinary iodine concentration and iodine content of salt consumed in households. RESULTS: Median thyroid volumes based on age were generally higher than those in iodine-sufficient areas and comparative to those reported in mild iodine-deficiency areas. Application of the updated WHO/ICCIDD reference values in iodine-replete European schoolchildren to the Mongolian children aged 10-12 years resulted in a goiter prevalence of 43.3%. The median value of urinary iodine concentration was 152.5 micro g/l (1.20 micro mol/l) and 40.3% of children excreted iodine below 100 micro g/l. Iodized salt (> 40 ppm) was consumed in 63.1% of households and in the children using noniodized salt their urinary iodine concentration was lower than those using ionized salt. In postpartum women, median thyroid volume and urinary iodine concentration were 11.3 ml and 107 micro g/l (0.84 micro mol/l), respectively, and 46% of women excreted less than 100 micro g/l (0.79 micro mol/l) of iodine. Of their neonates, 17.8% had elevated blood TSH levels (> 5 mU/l). In a 1999 survey, the goiter prevalence and ratio of low iodine excretion in schoolchildren decreased to 29.8% and 31.3%, respectively, while median urinary iodine concentration remain unchanged (160 micro g/l; 1.26 micro mol/l). CONCLUSION: The present study clearly indicates the presence of mild iodine deficiency in Mongolia. Enlarged thyroid gland and normal iodine excretion observed in schoolchildren living in Ulaan Baatar may result from the residual effects of iodine deficiency previously and presumably still exist in the city. Slight reduction in the rate of children with enlarged thyroid and low urinary iodine excretion after the onset of national iodinization programme suggests incomplete normalization of thyroid volume in children and that the correction of iodine deficiency is now in progress in Ulaan Baatar. Further nationwide surveys together with monitoring the progress of the national programme eliminating IDD are required in suburban areas surrounding the city and also in rural areas.     

The prevalence of anti-thyroid peroxidase antibodies and autoimmune thyroiditis in children and adolescents in an iodine replete area

BACKGROUND: The iodine supply of the population in Berlin has normalized during the last 5 Years. Therefore autoimmune thyroiditis has become the most important differential diagnosis in children and adolescents with goiter. OBJECTIVE: The aim of the present study was to define the prevalence of anti-thyroid peroxidase (TPO) antibodies and autoimmune thyroiditis in children and adolescents with a normalized iodine intake. DESIGN: To enable the measurement of antibodies to thyroid peroxidase (anti-TPO-Ab) in a large cohort, a method to determine anti-TPO-Ab in dried filter paper blood spots was established. In co-operation with pediatricians the antibody prevalence was assessed and data regarding thyroid size, echostructure and the medical history concerning iodine intake and familial thyroid diseases were collected. METHODS: 660 children and adolescents participated in the study; urinary iodine, TSH and TPO-Ab were measured and an ultrasound of the thyroid gland was performed. RESULTS: The sensitivity of the newly established filter paper assay was 91.8% and specificity was 100%. The results confirmed the improved iodine supply, with a median urinary iodine concentration of 139 microg iodine/g creatinine. The prevalence of anti-TPO-Ab was 3.4% with a female to male ratio of 2.7:1. CONCLUSION: The prevalence of anti-TPO-Ab is lower or equal to data reported from other iodine sufficient areas. Data from a moderate iodine deficiency in schoolchildren range from 0.0 to 7.3%. Using the new filter paper method field studies can be implemented to monitor the effect of changes in iodine nutrition on thyroid autoimmunity. Furthermore, this study on the prevalence of anti-TPO-Ab in a cohort of healthy children and adolescents in an iodine replete area can serve as reference data for future investigations and for the comparison with other groups of patients with increased risks for thyroid autoimmunity.     

The sardinian autoimmunity study. 4. Thyroid and islet cell autoantibodies in sardinian pregnant women at delivery: a cross-sectional study.

A high incidence of autoimmune Type 1 diabetes mellitus (DM) has been clearly established in Sardinia. Although systematic epidemiological studies are still not available, an increased prevalence of thyroid autoantibodies (ATA) has been documented in the Sardinian adult population as compared to other Italian regions, suggesting that thyroid autoimmune disease may also have increased. We carried out a preliminary study with the aim of determining the prevalence of serological markers of thyroid (anti-thyroperoxydase antibodies, TPOAb) and islet cell (ICA) autoimmunity in a large number (no.=2249) of sera obtained from cord-blood of Sardinian pregnant women at delivery. The prevalence of TPOAb was 11.9%, while ICA were detected in 59 cases (2.6%). A higher prevalence of TPOAb (6/17=35.3%) was found in sera with high ICA titers (> or = 20 JDF-U), as compared to sera with low ICA titers (5-19 JDF-U) and to ICA-negative sera (3/42=7,1%; chi2=5.4, p=0.02 and 258/2190=11,8%; chi2=6.8, p=0.009 respectively). Fourteen women (all ICA-negative) were diabetic: 4 had Type 1 and 10 had gestational DM; due to the low number, no correlation could be established between DM type and TPOAb prevalence and/or titer. These preliminary data indicate that ATA are frequently observed in the general population of Sardinian pregnant women at term. As a consequence, even the frequency of postpartum thyroiditis is expected to be high. Although ATA were not increased in women with clinical overt diabetes, a higher prevalence of ATA was found in women with high titers of circulating ICA. Our results also confirm that Sardinia represents, perhaps for its peculiar genetic characteristics, an ideal place to study organ-specific autoimmunity.     

Iodine deficiency in Azerbaijan after the discontinuation of an iodine prophylaxis program: reassessment of iodine intake and goiter prevalence in schoolchildren.

The goal of this study was to assess the prevalence of iodine deficiency (ID) in Azerbaijan after the discontinuation of an iodine prophylaxis program by assessing the prevalence of goiter, iodine intake, and thyroid function. The study included 942 schoolchildren (475 boys and 467 girls) ages 8-14 years, from 13 distinct regions. The survey included the following: (1) clinical evaluation; (2) assessment of thyroid volume both by ultrasound and by palpation; (3) determination of iodide in a morning urine specimen using the classic Sandel-Kolthoff reaction in 347 schoolchildren; (4) determinations of thyrotropin (TSH), triiodothyronine (T3), thyroxine (T4), thyroglobulin (Tg), and anti-thyroid peroxidase (TPO) in serum (n = 165) and TSH in whole blood spotted on filter paper (n = 942). The prevalence of goiter for the whole country was determined by ultrasound (US) to be 86% and by palpation 66%, reaching 100% in the mountainous regions of Caucasus. The median urinary iodine excretion (UIE) was 54 microg/L, reaching level of 26 and 39 microg/L in the Caucasus region. In conclusion, according to the World Health Organization (WHO) classification, Azerbaijan now has mild to moderate ID (median UIE, 54 microg/L) and in the mountainous regions with severe ID. The high prevalence of goiter and the low UIE emphasizes the need for urgent medical reintervention. An iodination program is now implemented by our team in the mountainous regions under the auspice of the government of Azerbaijan.     

Thyroid and celiac disease: clinical, serological, and echographic study

Objective: We sought to reevaluate the prevalence of thyroid dysfunction and thyroid autoimmunity in 47 patients with celiac disease; 91 healthy subjects were studied as controls. Both patients and controls were from Sardinia, Italy.
Methods: Diagnosis of celiac disease was made on the basis of clinical history, presence of positive antigliadin IgA (AGA-A) and IgG (AGA-G) antibodies, antireticulin antibodies (ARA), antiendomysium antibodies (EMA), and was confirmed by jejunal biopsy. HLA class II typing for DQB1 and DQA1 alleles was performed in 36/47 celiac patients. Thyroid was evaluated by palpation and echography; serum free thyroid hormones (FT4, FT3), thyrotropic hormone (TSH), and antithyroid peroxidase autoantibodies (anti-TPO) were assayed by radioimmunoassays.
Results: The prevalence of anti-TPO was higher in celiac patients (29.7%) than in healthy controls (9.6%) (   p < 0.001  ) and thyroid echography frequently displayed (42.5%) a hypoechogenic pattern. Five anti-TPO–positive celiac patients were hypothyroid (two overt, three subclinical). A higher but not significantly different prevalence of anti-TPO (3/ 7 = 42.8%) was found in celiac patients displaying the DQB1*0502 genotype, when compared with the remaining patients (8/29 = 27.6%).
Conclusions: An elevated prevalence of clinical and subclinical autoimmune thyroid autoimmunity was found in Sardinian celiac patients, especially in those displaying the DQB1*0502 genotype; this finding could be related to a particular genetic background of the Sardinian population.