Thyroid volumes in schoolchildren of the Emirates

Ultrasonographic determination of thyroid volume in infants and children from Aegean region of Turkey and comparison with national and international references

OBJECTIVES

Accurate diagnosis and follow-up of pediatric patients with thyroid disorders, depends on the availability of appropriate data for normal thyroid volume (TV). The aim of this study was to determine the TV by ultrasonography (US) in subjects from the newborn period up to 18 years of age from the Aegean region of Turkey.

METHODS

We measured the thyroid volumes in 513 children using US and compared them with the children's age, gender, standard deviation score (SDS) of body height (BH-SDS), body weight (BW-SDS), body mass index (BMI-SDS), and body surface area (BSA-SDS). The 3rd, 50th, and 97th percentiles of the age-dependent distribution of the TV were calculated and compared with national and international references.

RESULTS

The BH, BW, BMI, and BSA of all the participants were within the normal ranges for Turkish children. The TV was significantly positively correlated with age, gender, BH-SDS, BW-SDS, BMI-SDS, and BSA-SDS in all subjects (r=0.748, r=0.267, r=0.730, r=0.735, r=0.664 and r=0.735, respectively; p<0.0001 for all). The most important predictors for TV were age and BW-SDS, followed by BSA-SDS and BH-SDS. In multivariate regression, age and BW-SDS were the only significant independent predictors for TV. Our results were nearly similar to the corresponding data reported by the World Health Organisation in 2004.

CONCLUSIONS

The present study provides updated values for TV that can serve as a potential tool in differentiating the normal from the abnormal size of the thyroid gland in children aged 0-18 years from the Aegean region of Turkey.

Ultrasound measurement of thyroid volume in euthyroid children under 3 years of age

Objective

To establish ultrasound reference values for thyroid volumes in children up to 3 years of age, given that ultrasound of the thyroid is an essential examination in the diagnosis of childhood thyroid disease.

Materials and Methods

This was a prospective study conducted in an iodine-sufficient city in southeastern Brazil. A total of 100 healthy children underwent clinical evaluation, anthropometric examination, and cervical ultrasound in accordance with conventional protocols. We evaluated characteristics such as echotexture, thyroid lobe volume, and total thyroid volume. The children were divided into five groups, by age: < 2 months; 2-12 months; 12-18 months; 18-24 months; and 24-36 months.

Results

The mean thyroid volume was lower in the < 2 month age group than in the other groups (0.4 mL vs. 0.18-0.70 mL; p < 0.001). For the subjects between 2 and 36 months of age, the mean volume was 1.0 mL (range, 0.30-2.0 mL). No other significant differences were observed between groups, thyroid lobes, or gender. However, body mass index correlated significantly with total thyroid volume (r = 0.347; p = 0.001).

Conclusion

The mean thyroid dimensions were smallest in the < 2 month age group (0.35 ± 0.16 mL). For the subjects between 2 and 36 months of age, a reference value of 0.85 ± 0.42 mL can be used. Our data could guide the diagnostic investigation of thyroid disease, especially congenital hypothyroidism, in childhood.

Trend of Iodine Status in the Eastern Mediterranean Region and Impact of the Universal Salt Iodization Programs: a Narrative Review

Recognizing the importance of iodine deficiency as a single most important preventable cause of brain damage, World Health Organization (WHO) urged all countries to scale up salt iodization since 1991 where iodine deficiency was declared as a global public health problem. All countries committed to report on the national iodine status of school-aged children (6-12 years), every 3 years. This paper aims to evaluate the progress of countries in Eastern Mediterranean Region (EMR) toward the eradication of iodine deficiency disorders (IDD) and recommend operational action to support implementation of the WHO Regional Nutrition Strategy (2020-2030). Salt iodization in EMR has been scaled up with significant progress in increasing the proportion of dietary salt which is adequately iodized. As a result, many countries such as Qatar, Kuwait, Bahrain, Jordan, Oman, and Iran have achieved, or are now on the threshold of achieving IDD elimination. The WHO in coordination with United Nations Children's Fund is working with member states to ensure suitability of these achievements. Hence, efficient monitoring will help member states to measure the magnitude of IDD as a public health problem and to monitor the effects of the intervention on the iodine status of a population. Policy makers should take proactive steps to enforce mandatory regulatory measures for USI, through a multi-sectoral coordination, and careful assessments and estimates of iodine nutritional status. Coordination between the two national programs of USI and salt reduction intake is necessary.

A community-based ultrasound determination of normal thyroid volumes in the adult population, Assin North District, Ghana

Introduction

the purpose of this study was to measure thyroid volumes among normal sub-population of Ghanaians using ultrasonography in order to help provide preliminary local thyroid gland volume reference data for use in Ghana.

Methods

this was a cross-sectional study in which the thyroid glands of 320 normal adults aged 18 to 95 years from six (6) communities in the Assin North District of Ghana were examined using ultrasonography. The volumes of the left and right lobes were summed to constitute the total thyroid volume. Information on socio-demographic characteristics and anthropometric parameters of subjects were also collected. The data were summarized using mean, standard deviation and proportions, whilst inferential analysis was done using the T-test, ANOVA test and Pearson correlation.

Results

of the 320 adults examined, 284 (88.8%) were found to have normal thyroid glands. This consisted of 164 females and 120 males whose mean ages were 42.3 (±15.9) years and 45.4 (±15.9) years respectively. The overall mean total thyroid volume (MTTV) was 6.8±2.5 mL. This was greater in the males (7.1±2.7 mL) than in the females (6.6±2.2 mL). The MTTVs for three age groups; 30-39 years (7.1±2.1), 40-49 years (7.3±2.8 mL) and 50-59 years (7.1±3.0 mL) were greater than the overall MTTV. Thyroid volume had a positive correlation with body surface area (BSA) (r=0.119, p=0.046), but not with body mass index (BMI) (r=-0.021, p=0.719).

Conclusion

this study estimated local reference values much lower than the WHO/ICCIDD thyroid volume reference values. This calls for the need for nationally representative studies to inform the establishment of standard local reference values for Ghana.

A review of sonographic thyroid volume and iodine sufficiency in children: An Australian perspective

Sonographic measurement of the thyroid gland volume is a safe and reliable method for epidemiologic studies in iodine deficiency disorders. Several factors such as age, sex and anthropometric characteristics are known to be the determinants of thyroid gland size but the most widely studied is the effect of insufficient iodine intake. Low iodine intake induces enlargement of the thyroid gland known as goitre. The assessment of urinary iodine concentration alone is not reliable as it can vary daily within individuals. Urinary iodine concentration in conjunction with sonographic thyroid gland measurements is a widely used method of thyroid gland assessment. Establishment of normative thyroid volume is essential for the assessment of iodine deficiency disorders, and studies have been conducted in several countries. These studies have shown that thyroid gland volumes are likely population-specific even in iodine-sufficient countries limiting the effectiveness of international reference ranges. Based on currently available data of sonographic thyroid gland volume measurements and how they vary across populations of school children, this review argues for the establishment of population-specific reference ranges in regions such as Australia, which are now considered iodine-sufficient.

Normative Thyroid Volume by Ultrasonography in a Nigerian Pediatric Population

The objective was to establish normal thyroid volume in healthy infants and children, in a select Nigerian population. Using a portable ultrasound equipment with a 7.5-MHz transducer, 500 apparently healthy pediatric patients were sonographically evaluated. The volume for each thyroid lobe was obtained, as well as the summation of both left and right thyroid volumes, which represented the total volume. The mean and median thyroid volumes for the subgroups were 0.69 ± 0.38 cm3/0.7 cm3 (<1 year), 1.50 ± 0.68 cm3/1.4 cm3 (1–5 years), 2.75 ± 0.94 cm3/2.6 cm3 (6–10 years), 4.47 ± 2.83 cm3/3.7 cm3 (11–15 years), and 7.47 ± 4.81 cm3/5.9 cm3 (16 and 17 years). There was a significant difference ( P = .000) between the population studied and the World Health Organization/International Council for Control of Iodine Deficiency Disorders reference values. The baseline values derived for thyroid dimensions may form the basis for thyroid screening in these asymptomatic children.

Trimester specific reference ranges for serum TSH and Free T4 among United Arab Emirates pregnant women

BACKGROUND

The American Thyroid Association (ATA) recommended the establishment of population specific reference ranges for thyroid hormones during pregnancy. Initial studies conducted in the United Arab Emirates (UAE) in 2003 and 2004 on pregnant women published a considerably higher upper limit for thyroid stimulating hormone (TSH) than that proposed by ATA. The UAE was classified as a country with mild iodine deficiency at the time of this initial study. After the implementation of aggressive strategies to address iodine deficiency over the last decade, the UAE was recently declared as iodine sufficient. The current study re-evaluates the reference intervals for thyroid hormones for pregnant women in the UAE after the declaration of iodine sufficiency status.

METHODS

TSH and free thyroxin (FT4) from 414 UAE national pregnant females were analyzed to determine trimester specific reference ranges.

RESULTS

The upper limits of the TSH reference ranges were found to be significantly lower than previously reported, but still higher than those recommended by ATA in 2011.FT4 reference ranges were found to be slightly lower than previously reported.

CONCLUSION

TSH trimester specific reference ranges in UAE national pregnant women are higher than those recommended by ATA in 2011 but in keeping with the latest guidelines published in 2017. This should be considered while interpreting thyroid function tests in this population. Further studies including urinary iodine measurement, body mass index and larger numbers per partition in this population are recommended.

Effect of reducing iodine excess on children's goiter prevalence in areas with high iodine in drinking water

The purpose of the study was to evaluate the effect of removing iodized salt on children's goiter prevalence in high iodine area (HIA). A total of 452 and 459 children aged 8-10 years old were selected by simple random sampling method before and after removing iodized salt from their diet in three towns with median water iodine content of 150-300 µg/l in Hengshui city of Hebei province of China. Their goiter status was judged using the thyroid volume (Tvol) reference for body surface area recommended by the WHO. After removing iodized salt, children's overall median urinary iodine content (MUIC) decreased from 518 (IQR 347,735) µg/l to 416 µg/l (IQR 274,609). Children's MUIC across sex and age group decreased significantly. The overall goiter prevalence in the three towns significantly decreased from 32.96 % (149/452) to 6.54 % (30/459) (P < 0.001). The goiter prevalence in 8-, 9-, and 10-year-old children decreased, respectively, from 38.04 % (35/92), 30.57 % (59/193), and 32.93 % (55/167) to 6.10 % (10/164), 6.75 % (11/163), and 6.82 % (9/132). The goiter prevalence in boys and girls decreased from 34.01 % (83/244) and 31.73 % (66/208) to 6.19 % (14/225) and 6.87 % (16/234), respectively. The decreases in children's goiter prevalence across gender and age groups were all statistically significant. The present study revealed that children's goiter prevalence decreased significantly after removing iodized salt from their diet for about one and half years in the HIA in Hebei province.

Consumption of iodized salt may not represent a reliable indicator of iodine adequacy: Evidence from a cross-sectional study on schoolchildren living in an urban area of central Italy

OBJECTIVE

It has been established that iodine prophylaxis prevents endemic goiter. In this study we reported the amount of iodized salt sold by the retailers of Cassino, a city of central Italy. The aim of the study was to evaluate the effects of an iodine prophylaxis program started in 2005 on urinary iodine concentration (UIC) and thyroid volume (TV), and their correlation with anthropometric parameters in a population of schoolchildren.

METHODS

The study included 234 schoolchildren (119 girls and 115 boys) ages 13 to 14 y. Each student provided a morning urine sample for UIC determination, and TV was evaluated by ultrasonography. Body weight and height also were measured. Each participant completed a questionnaire reporting the presence of thyroid disease and the consumption of iodized salt and iodine-rich food.

RESULTS

The percentage of iodized salt sold by local markets was 42.4%. Median UIC in schoolchildren was 133.9 μg/L (range 33.2-819.5 μg/L), with 71 children having mild (range 50.1-99.9 μg/L) and 10 moderate (range 33.2-48.8 μg/L) iodine deficiency. Eleven children showed excessive iodine intake (range 300.4-819.5 μg/L). Median UIC was higher in children using iodized salt or consuming milk. Goiter prevalence was 3.8%. A positive correlation between TV and body weight, height, and surface was observed.

CONCLUSIONS

The data reported may suggest the presence of an adequate iodine intake in the population of Cassino despite the low percentage of iodized salt sold by local retailers. This indicates that silent iodine prophylaxis through the consumption of iodine-rich or iodine-enriched food is of importance in the prevention of iodine deficiency disorders.

Iodine-deficiency disorders in the Aseer region, south-western Saudi Arabia: 20 years after the national survey and universal salt iodization

OBJECTIVE

To study (i) the current prevalence of iodine-deficiency disorders among schoolchildren in south-western Saudi Arabia after universal salt iodization and (ii) the iodine content of table salts and water.

DESIGN

Cross-sectional study on a stratified proportional allocation sample of children. Thyroid gland enlargement was assessed clinically and by ultrasound scanning. Urine, table salt and water samples were taken to measure iodine content. Settings The Aseer region, south-western Saudi Arabia.

SUBJECTS

Schoolchildren aged 8-10 years.

RESULTS

The study included 3046 schoolchildren. The total goitre rate amounted to 24·0 %. Prevalence of enlarged thyroid by ultrasound was 22·7 %. The median urinary iodine concentration of the study sample amounted to 17·0 µg/l. The iodine content of table salt ranged from 0 to 112 mg/kg; 22·5 % of the table salt samples were below the recommended iodine content (15 mg/kg) set by WHO. The total goitre rate increased significantly from 19·8 % among children using table salt with iodine content ≥15 mg/kg to reach 48·5 % among children using table salt with 0 mg iodine/kg. Analysis of water samples taken from schools showed that the majority of water samples (78·8 %) had an iodine content of 0 µg/l.

CONCLUSIONS

The study documented that 18 years after the national study, and after more than a decade of universal salt iodization in Saudi Arabia, the problem of iodine-deficiency disorders is still endemic in the Aseer region. Efforts should focus on fostering advocacy and communication and ensuring the availability of adequately iodized salt.

Cytomorphologic spectrum of Hashimoto's thyroiditis and its clinical correlation: A retrospective study of 52 patients

BACKGROUND

Hashimoto's thyroiditis (HT) is an autoimmune disease and it is more prevalent in Asians. The incidence of HT seems to be increasing in the recent times. It is one of the most common cause of hypothyroidism. The purpose of this study is to review the cytomorphologic spectrum of HT and correlate it with clinical findings including thyroid function and antibody profile.

MATERIALS AND METHODS

We retrospectively analyzed the fine-needle aspiration (FNA) features of 52 HT patients. Based on cytomorphologic features patients were categorized into three groups. Clinical findings including thyroid function and thyroid peroxidase (TPO) antibody profile were correlated with cytomorphologic features in all three groups.

RESULTS

Majority of the patients were females and in 2(nd), 3(rd) and 4(th) decades. Diffuse goiter and thyroid hypofunction were the common findings. Significant number of patients had thyroid hyperfunction. Increased lymphocytes on the background and lymphocytic infiltration of thyroid follicular cell clusters in cytology smears were diagnostic of HT. The 32 patients showed elevated titers of TPO antibodies. In the early stages and mild form of the disease, results of thyroid function and anti TPO antibodies are quite variable.

CONCLUSIONS

HT is a disease of young and middle age and mostly occur in females. Clinical findings alone may not be adequate for definitive diagnosis. FNA is the gold standard for diagnosis. In the presence of abundant colloid, follicular hyperplasia or co-existing neoplasm, careful interpretation of cytology smears should be done. Aspiration from more than one site minimizes the diagnostic pitfalls.

Relationship between goiter and gender: a systematic review and meta-analysis

Several studies have reported inconsistent findings for the effect of gender on goiter prevalence. We undertook a systematic review and meta-analysis to investigate the effect of gender on goiter prevalence in different age groups and with differing iodine status. We systematically searched Medline, Embase, the Cochrane Library and Persian databases for trials published between 1950 and May 2012. We included studies assessing the goiter in both genders using palpation or ultrasonography, without age limitation. Summary estimates of pooled prevalence proportions were calculated with a quality effects model. Of 3286 candidate articles, 143 were eligible (606,714 participants). Proportional prevalence of goiter was greater for females than males 0.54 (95 % CI = 0.53-0.56) versus 0.46 (95 % CI = 0.44-0.47), these proportions for subgroups of longstanding iodine deficiency and recent (<10 years) iodine sufficiency were 0.59 versus 0.41 and 0.54 versus 0.46, respectively; however, no gender difference was observed in proportional prevalence of goiter in the subgroup of longstanding (>10 years) iodine sufficiency (0.50 vs. 0.50). These proportions for grade 1 of goiter were 0.54 versus 0.46 and for grade 2 were 0.63 versus 0.37; for children were 0.54 versus 0.46 and for adults were 0.74 versus 0.26 for females and males, respectively. Subgroup analyses showed that there was an increasing trend in gender differences around the age of 15 years. Goiter is more frequent in females. This gender difference in prevalence of goiter is more prominent in iodine-deficient areas, and with grade 2 of goiter, notably after puberty.

Determination of thyroid volume by ultrasonography among schoolchildren in Philippines

OBJECTIVE

Iodine deficiency is defined by the goiter and the urinary iodine concentration. However, a lack of local thyroid volume reference data resulted in the vague definition of goiter, especially in school-aged children. The aim of this paper was to determine the thyroid volumes by ultrasonography in schoolchildren aged 6 to 12 years living in Cagayan areas in Philippine.

METHODS

Cross-sectional thyroid ultrasonographic data of 158 schoolchildren aged 6-12 years from Tuguegarao and Lagum in Cagayan valley, Philippine were used. Thyroid volumes were compared based on logistic issue and urban and rural area and compared with other previously reported data.

RESULTS

The mean values of thyroid volume in Tuguerago and Lagum were 2.99 ± 1.34 mL and 2.42 ± 0.92 mL. The thyroid size was significantly in association with age (P < 0.00), weight (P < 0.00), height (P < 0.00), and BSA (P < 0.00) by Pearson's correlation. The median thyroid volumes of schoolchildren investigated in this study were generally low compared to international reference data by age group but not by BSA.

CONCLUSIONS

We propose for the first time local reference ultrasound values for thyroid volumes in 6-12 aged schoolchildren that should be used for monitoring iodine deficiency disorders.

Local reference ranges of thyroid volume in sudanese normal subjects using ultrasound

This study aimed to establish a local reference of thyroid volume in Sudanese normal subjects using ultrasound. A total of 103 healthy subjects were studied, 28 (27.18%) females and 75 (72.82%) males. Thyroid volume was estimated using ellipsoid formula. The mean age and range of the subjects was 21.8 (19–29) years; the mean body mass index (BMI) was 22.3 (16.46–26.07) kg/m². The overall mean volume ± SD volume of the thyroid gland for both lobes in all the patients studied was 6.44 ± 2.44 mL. The mean volume for both lobes in females and males were 5.78 ± 1.96 mL and 6.69 ± 2.56 mL, respectively. The males' thyroid volume was greater than the females'. The mean volume of the right and left lobes of the thyroid gland in males and females were 3.38 ± 1.37 mL and 3.09 ± 1.24 mL, respectively. The right thyroid lobe volume was greater than the left. The values obtained in this study were lower than those reported from previous studies.

Assessment of urinary iodine excretion among normal Kuwaiti adults

This study was performed to investigate the status of iodine intake among the Kuwaiti population and its effect on thyroid function. The study group was comprised of 139 females and 86 males with a mean age of 33 and 35 years, respectively. Urinary iodine excretion (UIE) and serum free T4 (FT4), thyrotropin hormone (TSH), antiperoxidase antibodies (anti- TPOAb), and antithyroglobulin antibodies (anti-TGAb) were determined. Median UIE was 148 μg/L (within the recommended level by the World Health Organization [WHO]). However, UIE levels of <100 and <50 μg/L were detected in both male and female groups, respectively. Serum levels of TSH and FT4 were normal for all except one of the participants who suffered from hyperthyroidism, possibly as a result of elevated iodine intake, which was reflected in an increased UIE of 590 μg/L. Elevated anti-TPOAb >75 IU/mL and anti-TGAb >150 IU/mL were detected in 15% and 34% of subjects; only 10% of them had elevated levels of both anti-TPOAb and anti-TGAb. Thus, based on the WHO recommendations, the iodine intake for the Kuwaiti population is adequate. However, it is recommended that a national study be conducted by the appropriate authority in order to eliminate any artifacts which may have appeared in this study.

Beneficial effects of iodized salt prophylaxis on thyroid volume in an iodine deficient area of southern Italy

OBJECTIVE AND SUBJECTS

Goitre prevalence in school-age children is an indicator of the severity of iodine deficiency disorders (IDD) in an endemic area. The aims of the present study were (i) to provide ultrasound thyroid volume (TV) reference values in a healthy population of school-children aged 11-14 year living in iodine-sufficient areas of Calabria region (ii) to assess both goitre prevalence and urinary iodine (UI) concentration in all children aged 11-14 year from four mildly iodine-deficient areas in which we have carried out a program of salt iodization and (iii) to evaluate the efficacy of the iodoprophylaxis in an adult population living in a small village of the same endemic area.

DESIGN

Cross-sectional and prospective studies.

METHODS

TV was assessed by ultrasonography and iodine intake was estimated by measuring iodine excretion in spot urine samples. Results We provided the ultrasound normal reference values as a function of age and body surface area, which displayed significant differences from those recommended by the World Health Organization. By adopting local criteria, the prevalence of goitre in children ranged from 23.4% to 27.7% normalized for age and body surface area, respectively, while the UI excretion was < 100 microg/l in 38% of subjects studied. In an adult population living in the same endemic area, goitre prevalence was lowest in the 18-27-year-old age group, and increased progressively with age.

CONCLUSION

We propose for the first time local reference ultrasound values for TV in a population of 11-14-year-old school-children that should be used for monitoring IDDs and have demonstrated the beneficial effects of iodoprophylaxis in consistent with reduced goitre prevalence in children and in the young adult population studied.

Lymphocytic thyroiditis--is cytological grading significant? A correlation of grades with clinical, biochemical, ultrasonographic and radionuclide parameters

Background

Clinical, biochemical, ultrasonographic, radionuclide and cytomorphological observations in Lymphocytic thyroiditis (LT), to define the cytological grading criteria on smears and correlation of grades with above parameters.

Methods

This prospective study was conducted on 76 patients attending the Fine needle aspiration cytology clinic of a tertiary care institute in North India. The various parameters like patients' clinical presentation, thyroid antimicrosomal antibodies, hormonal profiles, radionuclide thyroid scan and thyroid ultrasound were studied. Fine needle aspiration of thyroid gland and grading of thyroiditis was done on smears. The grades were correlated with above parameters and the correlation indices were evaluated statistically.

Results

Most of the patients were females (70, 92.11%) who presented with a diffuse goiter (68, 89.47%). Hypothyroid features (56, 73.68%) and elevated TSH (75, 98.68%) were common, but radioiodide uptake was low or normal in majority of patients. Thyroid antimicrosomal antibody was elevated in 46/70 (65.71%) patients. Cytomorphology in fine needle aspirates was diagnostic of lymphocytic thyroiditis in 75 (98.68%) patients. Most of them had grade I/II disease by cytology. No correlation was observed between grades of cytomorphology and clinical, biochemical, ultrasonographic and radionuclide parameters.

Conclusion

Despite the availability of several tests for diagnosis of LT, FNAC remains the gold standard. The grades of thyroiditis at cytology however do not correlate with clinical, biochemical, radionuclide and ultrasonographic parameters.

Prevalence of overweight and obesity among children in the United Arab Emirates

The aim of the study was to determine the prevalence of overweight and obesity in children in the United Arab Emirates (UAE). Secondary analysis was undertaken of data on 4381 children aged 5-17 years from the 1999 UAE-National Iodine Deficiency Surveillance Study. Data on weight and height from that study were used to calculate body mass index. The prevalence of overweight and obesity was estimated using International Obesity Task Force criteria. Overall, 944 (21.5%) of children were overweight and 601 (13.7%) of these were obese. More girls than boys were overweight (22.9% vs. 20.2%; P < or = 0.001). Non-citizen girls were more likely to be obese (odds ratios [OR] 1.767, 95% confidence intervals [CI] 1.48-2.102) than UAE girls. Boys in the rural areas had the lowest prevalence (23.6%) and were the least likely of all the children to be either overweight (OR 0.785, 95% CI 0.629-0.974) or obese 0.732 (95% CI 0.591-0.912). This study demonstrates a high prevalence of overweight in children in the UAE. Prompt actions are needed to initiate preventative and interventionist strategies to reverse the trend of this emerging epidemic.

Goiter prevalence and urinary iodine status in urban and rural/mountain areas of Piedmont region

Piedmont region was reported in the 70s as a mild iodine-deficient area with a goiter prevalence > 10%. This study aimed at characterizing the current status of iodine deficiency in Piedmont, with special attention to putative differences between urban and rural/mountain areas. A cross-sectional, observational study was performed according to the surveillance methods for iodine deficiency disorders recommended by the World Health Organization (WHO). Ultrasound local thyroid volume reference values and median urinary iodine concentration were obtained in 2178 schoolchildren aged 11-15 yr, resident in Piedmont region for more than 5 yr to assess both goiter prevalence and iodine intake. Anamnestic and anthropometric data, thyroid volume by both bimanual palpation and ultrasound were assessed, and spot urinary iodine samples were collected. The median urinary iodine concentration was 115.8 microg/l and the prevalence of goiter 3.1%, indicating this area as iodine-sufficient. Nevertheless, 39% of the schoolchild population had urinary iodine levels < 100 microg/l and 6.8% < 50 microg/l. No differences in goiter prevalence and median urinary iodine excretion were observed between urban and rural/ mountain populations. In conclusion, Piedmont is now an iodine-sufficient region. As no programs of salt iodization have been carried out in the last 30 yr, a silent iodine replacement has occurred. Despite a sufficient median urinary iodine excretion, a program of iodine prophylaxis is strongly recommended due to a large part of iodine-deficient population.

Thyroid volume and urinary iodine excretion in the schoolchild population of a Northwestern Italian sub-Alp metropolitan area

Iodine deficiency is recognised as a major preventable public-health worldwide problem. The aim of this study is to assess local reference values for thyroid volume, and give a snapshot of the epidemiology of goiter and iodine nutritional status of the Turin schoolchild population. Sonographic thyroid volume and median urinary iodine excretion were obtained in 1067 schoolchildren aged 11-15 yr resident in Turin for more than 5 yr to assess both goiter prevalence and iodine intake. All the subjects were asked to fill in a questionnaire about their life habits. Anamnestic and anthropometric data, thyroid volume by both bimanual palpation and ultrasonography were assessed, and spot urinary iodine samples were collected. The results show that the median urinary iodine concentration is 113.1 microg/l and the prevalence of goiter <5%, indicating this area as iodine-sufficient. Nevertheless, 40.5% of the schoolchild population has urinary iodine levels lower than the cut-off level recommended as iodine-sufficiency. Interestingly, the high relative prevalence of ultrasound features of autoimmune thyroid disease suggests autoimmune-thyroiditis as a frequent thyroid disease in Turin schoolchildren. As no active programs of salt, milk or water iodisation have ever been carried out, a silent iodine prophylaxis has probably occurred in the city. Despite a sufficient median urinary iodine excretion, a focused program of iodine prophylaxis should be developed due to the presence of a large rate of iodine-deficient population.