Normal thyroid volume by ultrasonography in healthy children

Genetic etiology in patients diagnosed with congenital hypothyroidism with new-generation sequencing: A single-center experience

AIM

Congenital hypothyroidism (CH) is the most common endocrine disorder of the newborn; it is seen in every 3000-4000 births. Genetic features can guide treatment for patients with in situ glands. The present study aimed to contribute to the literature on CH variants and to show the benefit that genetic analysis can provide to patients in follow-up.

METHOD

A total of 52 patients (47 families) diagnosed with CH were included in the study. Overall, 32 target genes involved in thyroid physiology were investigated by next-generation sequencing (NGS).

RESULTS

In total, 29 (55 %) of the patients were male, and the rate of dysgenesis was 19.2 %. In this study, 29 of 52 patients had at least one variant in one gene involved in CH (n = 29, 33 different variants) (Including likely benign variants and variants of unknown significance). There were 21 patients (40.3 %) with gland in situ. The most common variant was DUOX2 (20 %). The second most common variants were those in the TPO and TG genes (15 % and 15 %, respectively); 41.1 % of these were variants of uncertain significance (VUS), 26.4 % were pathogenic, 23.5 % were likely benign, and 11.7 % were likely pathogenic. On the basis of their zygosity, we identified 73.5 % heterozygous, 17.6 % homozygous, and 8.9 % combined heterozygous variants. There were mutant variants in two genes in six patients and three in one patient.

CONCLUSION

This study found a variant in 55 % of the patients and shed light on the etiology of some cases of CH. The frequency of VUS was high. Although variants were identified in this study, their implication in the etiology of CH is not certain and, for most of the patients, it is also not sufficient for explaining the pathology with the current state of knowledge.

Clinical, biochemical, and radiological follow-up results of children and adolescents with Hashimoto's thyroiditis: a single-center experience

OBJECTIVES

Hashimoto's thyroiditis (HT) is the most common cause of goiter and acquired hypothyroidism in children and adolescents, especially in areas without endemic iodine deficiency. We aimed to evaluate the follow-up results of children and adolescents diagnosed with HT, including clinical, biochemical, and radiological findings and treatment approaches.

METHODS

HT patients, who were diagnosed between 2012 and 2018 years in a single-center, were assessed retrospectively.

RESULTS

Two hundred and twenty-four cases were included in the study, 75.9% of whom were girls (female/male ratio: 3.1) and 66.5% were pubertal. The median age of the cases at first admission was 12.5 (9.2-15) years. The median follow-up period of 196 patients, who continued their follow-up regularly, was 2.1 (0.7-4.8) years. When autoantibody levels were analyzed according to gender, mean anti-Tg levels were higher in girls (p=0.028), whereas anti-TPO levels were similar (p=0.372). A nodule was detected in the ultrasonographic follow-up of 29 (13%) patients. Papillary thyroid carcinoma was observed in 10.3% (n=3) of those with nodules. When the last ultrasonography findings of 188 patients with available radiological follow-up data were compared with their initial evaluation, the rate of heterogeneous parenchymal echogenicity increased significantly (p=0.008). The need for l-thyroxine dosage augmented over time.

CONCLUSIONS

Although HT is more common in adolescent girls, it can be encountered in both genders and at all ages in childhood. The incidence of malignancy was not higher in patients with nodules associated with HT than the reported incidences of malignancy in nodules not associated with HT.

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.

Assessment of thyroid gland vascularity with superb microvascular imaging in healthy children and its relationship with potential factors

Objectives To define thyroid gland vascularity index (VI) values in healthy children with the superb microvascular imaging (SMI) method and to assess whether or not there is a correlation with potential factors that may affect these values. Methods This prospective study included a total of 138 children, their ages varying from 3-17 years. Cases were divided into three subgroups according to age: 3-6, 7-12 and 13-17 years. Gender, age, height, weight, body mass index (BMI), thyroid-stimulating hormone (TSH) and free thyroxine (fT4) values were recorded. Volume and SMI measurements were performed with a 14 L5 mHz linear transducer. VI measurements were performed in the transverse and longitudinal planes and correlation with basic descriptive data was researched. Results Mean age was 11.14 ± 3.34 years and BMI was 19.95 ± 4.92. VI values were 4.59 ± 2.34 in the right lobe and 4.23 ± 2.73 for the left lobe, with no significant difference identified. There were no significant differences in mean VI for all parenchyma regarding gender and age groups. While there was no correlation identified with mean VI for all parenchyma with TSH and fT4, there was, however, a negative correlation with BMI. Conclusions Reference VI values for normal thyroid glands in healthy children and adolescents were defined with the SMI method. There was no correlation between the VI values and age, gender, volume, TSH and fT4 values, while there was a negative significant correlation with BMI.

Pediatric thyroid ultrasound: a radiologist's checklist

Ultrasonography (US) is the imaging method of choice for evaluating the pediatric thyroid gland, complemented by scintigraphy and thyroid function tests, especially when evaluating children with suspected congenital hypothyroidism, goiter, infectious or autoimmune diseases, or neoplasm. Diagnostic considerations in newborns with congenital hypothyroidism mainly include dysgenesis, dyshormonogenesis, transient hypothyroidism and central (hypophyseal) hypothyroidism. The midline of the neck should be scrutinized for thyroid tissue from the floor of the mouth to the thoracic inlet. Cystic and echogenic ultimobranchial remnants should not be misinterpreted as orthotopic thyroid tissue. Diffuse thyroid diseases affect older children; these comprise Hashimoto and Graves diseases and infectious thyroiditis and exhibit features similar to those in adults. It is important to note that the diffuse sclerosing variant of papillary thyroid cancer can complicate thyroiditis and should not be confused with Hashimoto disease. In children with solid nodules the threshold for fine-needle aspiration biopsy or surgery should be lower compared to adults because of a higher likelihood of malignancy compared with adults. Biopsy should be considered in nodules with suspicious ultrasonographic features, even when smaller than 1 cm. Adult classification systems of thyroid nodules, although useful, are not sufficient to safely discriminate the nodules' likelihood of malignancy in children. We describe key sonographic findings and suggest a standard checklist that might be considered while performing and interpreting thyroid US in neonates and children.

Quantitative Assessment of Thyroid Glands in Healthy Children With Shear Wave Elastography

The local shear wave speed (in meters per second) and Young modulus (in kilopascals) of normal thyroid glands were defined in healthy children to determine reference values.This prospective study assessed 107 pediatric cases (age interval, 3-17 years; mean, 9.37 ± 3.68 years), including 52 boys and 55 girls. The study group included children without thyroid gland disease (autoimmune, infectious, or neoplastic). Data about the sex, age, weight, height, and body mass index (BMI) of the subjects were recorded for all subjects. Elasticity values were measured from 3 different sites in both thyroid lobes and averaged.Median values for elasticity and shear wave velocity measured in bilateral thyroid lobes were 6.38 ± 1.97 kPa (range, 3.00-12.5 kPa) and 1.45 ± 0.21 m/s (range, 1.03-2.04 m/s) on the right and 8.81 ± 3.00 kPa (range, 3.80-22.6 kPa) and 1.69 ± 0.26 m/s (range, 1.13-2.68 m/s) on the left. There was no significant difference between the elasticity values for the right and left thyroid lobes between boys and girls. There was a positive correlation between right thyroid lobe mean elasticity (in kilopascals) and shear wave velocity (in meters per second) values with age, BMI, and right thyroid lobe volume in the whole group. No significant correlation was found between left thyroid lobe mean elasticity (in kilopascals) and shear wave velocity (in meters per second) values with age, BMI, and left thyroid lobe volume in the study population.This study determined mean elasticity and shear wave velocity values for thyroid gland in healthy children. This information can be used as a baseline for the investigation of thyroid diseases.

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.

Quantitative Assessment of Thyroid, Submandibular, and Parotid Glands Elasticity With Shear-Wave Elastography in Children

Tissue elasticity is becoming a more commonly used parameter in evaluation of parenchyma in inflammatory diseases. Considering the changes in the thyroid and salivary glands with adolescence, determination of mean elasticity ranges with a function of age is necessary to apply ultrasound elastography more widely in the pediatric population.The thyroid, submandibular, and parotid glands of 127 healthy volunteers (66 males, 61 females; mean age = 10.3 ± 3.9 years; range = 3-17 years) were evaluated with shear-wave elastography.The mean elasticity values for the thyroid, submandibular, and parotid glands were 14.6 ± 3.3, 11.8 ± 2.2, and 11.8 ± 2.6 kPa, respectively. There was a significant positive correlation between age and elasticity of the thyroid, submandibular, and parotid glands. There was a significant correlation between age and elasticity value of the thyroid gland adjusted for weight and height.This study provided the baseline quantitative elasticity measures of thyroid, submandibular, and parotid glands, which would be a reference for upcoming studies. In addition, an increase in elasticity value in thyroid gland as a function of age independent of change in weight and height was demonstrated.

Effects of 1-year growth hormone replacement therapy on thyroid volume and function of the children and adolescents with idiopathic growth hormone deficiency

BACKGROUND

There are different opinions about the effects of growth hormone replacement therapy (GHRT) on thyroid function and volume. This study aimed to assess the effects of GHRT on thyroid volume and function in the children and adolescents with growth hormone (GH) deficiency.

METHODS

A total of 29 patients diagnosed with GH deficiency were enrolled in the study. The control group consisted of 29 cases matched for age, gender and pubertal period with the patients. Thyroid function tests and insulin-like growth factor levels were measured, simultaneously thyroid volumes were assessed by ultrasonography at the initiation period and at the end of GHRT.

RESULTS

Thyroid volumes of the patient group was -0.55±1.1 standard deviations (SDs) initially; whereas at the end of 1 year it was found to be -0.29±1.29 SDs and both SDs of thyroid volumes did not differ significantly. The SDs of thyroid volume of the control group was -0.85±1.03 SDs initially and -0.72±0.85 SDs at the end of 1 year; and they did not differ significantly. On the other hand, after GHRT of 1 year, thyroid stimulating hormone (TSH) and free thyroxine (T4) levels decreased.

CONCLUSIONS

It was observed that SDs of thyroid gland volumes did not change in GH deficient children and adolescents after GHRT.

Congenital Hypothyroidism: Role of Nuclear Medicine

Thyroid scintigraphy holds a key place in the etiologic workup of neonatal hypothyroidism. Routine screening for this disorder in maternity hospitals in industrialized countries, for nearly 40 years, has permitted early treatment and thereby helped to prevent its physical and mental complications. Neonatal hypothyroidism affects approximately 1 in 3000 births. The most common causes are abnormal thyroid gland development and defective hormone synthesis by an eutopic thyroid gland. The incidence of the latter has risen in recent years, for reasons that remain unclear. A thorough etiologic workup helps to determine the disease type. Current guidelines recommend thyroid imaging by means of ultrasound and scintigraphy. Ultrasound should be done by a practitioner trained to examine the cervical region of newborns, as the thyroid is very small and must be distinguished from the particular aspect of the "thyroid empty lodge." Ultrasound lacks sensitivity for detecting small ectopic glands but is the gold standard for measuring thyroid dimensions. Scintigraphy provides an etiologic diagnosis in most cases. The two isotopes used in this setting are technetium-99m and iodine-123. The latter isotope gives more contrast and allows the perchlorate discharge test to be performed to detect abnormal iodide organification in the neonate with an eutopic thyroid. If scintigraphy cannot be performed during the neonatal period, a postponed procedure can be achieved after 3 years of age. Close cooperation between the nuclear medicine physician and the pediatric endocrinologist is crucial for timely and optimized scintigraphy.

Interpretation of thyroid glands in a group of healthy children: real-time ultrasonography elastography study

BACKGROUND

This study aimed to determine the strain index (SI) of normal thyroid parenchyma in a group of healthy children, using ultrasound elastography (USE).

METHODS

The participants consisted of 54 healthy children. The USE of the normal thyroid parenchyma was performed by using the Hitachi Hi VisionPreirus model ultrasonography (US) device. By following sinusoidal waves at the base of the screen, regular and slight compressions and decompressions were made by the transducer. After the regular sinusoidal waves were acquired, standard region of interest (ROI) circles were used to measure the SI values of the thyroid glands by placing one ROI on a superficial part of the normal thyroid gland parenchyma and the other on the adjacent soft tissue at the same depth (within 10-mm proximity). Three measurements were obtained for each (right and left) thyroid gland, and the mean value was used for statistics.

RESULTS

The mean SI value of normal thyroid glands was 0.54±0.38 for the whole group. There was no statistically significant difference between girls and boys on the basis of age, weight, height, BMI (body mass index), and thyroid SI values (p=0.15, p=0.18, p=0.12, p=0.31, and p=0.96, respectively). No correlation was found between thyroid gland SI values and each of the following variables: age (r=0.22, p=0.15), gender (r=0.007, p=0.96), and BMI (r=0.26, p=0.09).

CONCLUSIONS

The study determined the normal elasticity values of thyroid glands in healthy children. Such information can serve as a baseline from which thyroid diseases can be examined.

Celiac disease in children and adolescents with Hashimoto Thyroiditis

AIM

The aim of this study was to evaluate clinical and laboratory findings and determine the prevalence of celiac disease (CD) in children with Hashimoto thyroiditis (HT).

MATERIAL AND METHODS

The data of a total of 80 patients with positive anti-thyroid antibodies who were aged between 6 and 17.9 years were retrospectively studied. Age, gender, complaints at the time of presentation, family history of thyroid disorders, clinical and laboratory findings were recorded. The levels of thyrotropin, free thyroxin, thyroid autoantibodies (thyroid peroxidase and thyroglobulin antibodies), immunoglobulin A (IgA), anti-tissue transglutaminase antibodies (IgA-tTG), and thyroid ultrasonography findings were enrolled.

RESULTS

Eighty patients (65 females (81.2%) and 15 males (18,8%)) were included in the study. Family history of thyroid disease was present in 38 (47.5%) patients. The most common complaints at the time of presentation were goiter (%30) and weight gain (%25). Forty three (53.8%), 23 (28.7%), and 14 (17.5%) patients presented with euthyroidism, subclinical hypothyroidism and obvious hypothyroidism. Thirty seven (46.2%) patients had goiter. IgA-tTG was found to be positive after a diagnosis of HT was made in only one patient (1.25%) and the diagnosis of CD was confirmed when intestinal biopsy of this patient revealed villus atrophy, crypt hyperplasia and increase in the intraepithelial lymphocyte count.

CONCLUSIONS

In our study, it was found that the most common complaints at presentation in patients with a diagnosis of hashimoto thyroiditis included goiter, weakness and weight gain and the prevalence of celiac diseases was found to be 1.25% (1/80). This study shows that the prevalence of CD in patients with a diagnosis of HT is higher compared to the prevalence in the healthy pediatric population.

Thyroid gland volume of schoolchildren in the North of Iran: Comparison with other studies

BACKGROUND

Few studies have shown the limitation of the World Health Organization (WHO)/ International Council for the Control of Iodine Deficiency (ICCIDD)-adopted thyroid gland volume references as universal normative values for thyroid gland volume. So we decided to measure thyroid gland volume by sonography in schoolchildren in Rasht, Gilan Province, Iran - Rasht is a metropolitan city on the Caspian Sea coast - and compare them to WHO normative values.

MATERIALS AND METHODS

In a cross-sectional study, 2,522 schoolchildren, aged 6-13 years, in Rasht, Gilan Province, Iran were selected by multistage random sampling. Data were collected on their age, sex, weight, height, body surface area (BSA), and thyroid gland size by palpation and sonography. The terminal phalange of thumb finger volume was calculated with the same formula used in sonography, for the thyroid gland in 1,085 of these cases.

RESULTS

Goiter prevalence was 64% (1613 cases) by palpation, 76.1% (1228 subjects) grade I and 23.9% (385 cases) grade II. The mean thyroid gland volume in girls was more than boys (3.67 ± 1.89 mL vs 3.41 ± 1.58 mL, P < 0.0001). According to the 1997 WHO thyroid gland volume reference, none of the children had goiter based on BSA and age even in those with grade II goiters (23.9%). In contrast, the median thyroid gland volume in our cases was larger than the 2004 WHO reference. The best single predictor of thyroid gland volume was age (R (2) = 0.391, P < 0.0001) followed by BSA (R (2) = 0.151, P < 0.0001). There was also a significant difference between thyroid gland and finger volume in all grades of goiter and grade II goiters (3 ± 1.4 mL vs 9.59 ± 2.4 mL; P < 0.0001. 4.3 ± 1.4 mL vs 9.3 ± 2.5 mL; P < 0.0001).

CONCLUSION

The WHO standards for thyroid gland volume by sonography may underestimate or overestimate the goiter prevalence in many areas and populations. Finger volume was much larger than thyroid gland volume in even visible goiters.

Investigation of autoimmune diseases accompanying Hashimoto's thyroiditis in children and adolescents and evaluation of cardiac signs

OBJECTIVE

In the present study, it was aimed to investigate the concomitance of additional cardiac problems, mainly mitral valve prolapse, in adolescents and pediatric patients with Hashimoto's thyroiditis, by screening autoimmune markers.

MATERIALS AND METHODS

Fifty-seven euthyroid patients, who applied to the Pediatric Endocrinology clinic at our institution with marked symptoms of hypothyroidism at the time of diagnosis, and were diagnosed and treated for Hashimoto's thyroiditis, were included in the present study. All patients were evaluated by performing non-organ specific autoantibodies which could be tested at our institution, thyroid ultrasonography, two-dimensional echocardiography, and 24-h holter monitorization.

RESULTS

Of the 57 cases with Hashimoto's thyroiditis, 48 (84.2%) were female, and nine (15.8%) were male. In the echocardiographic evaluation, mitral valve problems were detected in 10 (17.5%) of all cases; mitral valve prolapse was diagnosed in eight (seven females and one male) cases, and mitral insufficiency was diagnosed in two female cases. First-degree atrioventricular block was observed in only two patients during 24-h holter monitorization. Different non-organ specific autoantibody positivity was distributed as antinuclear antibody in 15 (26.3%) cases, anticardiolipin IgG in two cases, anticardiolipin IgM in three cases, tissue transglutaminase IgA in one, glutamic acid decarboxylase in one, anti-insulin antibody in four cases, antiphospholipid IgG in one, and antiphospholipid IgM in one case.

CONCLUSION

It should be underlined that patients with Hashimoto's thyroiditis should to be followed up closely for mitral valve prolapse and accompanying autoimmune diseases.

Normative Data of Thyroid Volume-Ultrasonographic Evaluation of 422 Subjects Aged 0-55 Years

OBJECTIVE

To establish local normative data of thyroid volume assessed by ultrasonography in subjects aged 0-55 years living in İstanbul, Turkey.

METHODS

Subjects without any known history of thyroid disease, of major surgery and/or chronic disease were enrolled in the study and evaluated by physical examination and thyroid ultrasonography. Thyroid gland and isthmus at usual location, each lateral lobe volume with three dimensions, ectopic thyroid tissue and echogenicity of the gland were assessed.

RESULTS

Initially, 494 subjects were enrolled in the study. Subjects showing heterogeneous thyroid parenchyma (n=21) and/or nodule (n=51) in ultrasonography were excluded. Final analysis covered 422 subjects (216 males, 206 females). Thyroid volume was found to significantly correlate with height, weight, age and body surface area (r=0.661, r=0.712, r=0.772 and r=0.779, respectively; p<0.0001 for all). These correlations were even stronger in subjects younger than 18 years (r=0.758, r=0.800, r=0.815 and r=0.802, respectively; p<0.0001 for all).

CONCLUSION

The study provides updated reference norms for thyroid volume in Turkish subjects which can be used in the diagnosis and follow-up of patients with thyroid diseases.

Diseases accompanying congenital hypothyroidism

INTRODUCTION

Extrathyroidal abnormality incidence and especially the incidence of congenital cardiac disease are increased with congenital hypothyroidism. In this present study, it is aimed to evaluate patients who were being followed up for congenital hypothyroidism for accompanying diseases, and to compare impacts of accompanying diseases on prognosis under the light of published articles in the literature.

MATERIAL AND METHODS

A total of 400 cases which were diagnosed with, treated and followed up for congenital hypothyroidism in our clinic were retrospectively evaluated. Cases with complaining symptoms and without any complaints, but were diagnosed with hypothyroidism as the result of screening tests were enrolled in the study.

RESULTS

Of 400 subjects included due to congenital hypothyroidism, 186 (46.5%) were girls and 214 (53.5%) were boys. Accompanying diseases were diagnosed in 113 cases (28.2%). Accompanying diseases according to the frequency order were congenital cardiac disease (n=32, 8.0%), Down syndrome (n=25, 6.3%), inguinal hernia (n=21, 5.30%), undescended testicles (n=8, 2.0%), GH deficiency (n=4, 1.0%), and some other systemic diseases (n=23, 5.8%). In cases accompanied by congenital cardiac diseases, ventricular septal defect (n=10), atrial septal defect (n=9), pulmonary stenosis (n=7), patent ductus arteriosis (n=7), and aortic coarctation (n=3) were detected.

CONCLUSION

In this present study, it was defined that approximately one third of patients with congenital hypothyroidism had an accompanying disease, and cardiac diseases were the most common problem. It is concluded that evaluation of congenital hypothyroidism cases for accompanying diseases, detailed cardiological examination being in the first order, is important for prognosis.

Pitfalls in the diagnosis of thyroid dysgenesis by thyroid ultrasonography and scintigraphy

OBJECTIVES

We aimed to investigate the reliability of thyroid ultrasonography (US) and scintigraphy in determining the type of thyroid dysgenesis (TD).

METHODS

The study included 82 children (8.0±5.6 years) with a diagnosis of TD by thyroid scintigraphy with (99m)Tc and/or US. The patients were re-evaluated 6.0±5.1 years after the diagnosis. Thyroid US was performed in all cases, regardless of the previous US imaging. Scintigraphy images performed at the time of diagnoses (n=60) were re-evaluated during the study. Those who had no scintigraphy at the time of diagnosis (n=22) or had discordant findings with US (n=6) underwent a new scintigraphy.

RESULTS

Scintigraphies revealed no uptake in 37, ectopia in 35, and hypoplasia in 10 cases. The sensitivity vs specificity for US to detect athyreosis, ectopia, and hypoplasia at the time of initial diagnoses was 90.5 vs 47.8, 10 vs 100, and 100 vs 80.4% respectively. The sensitivity vs specificity for scintigraphy at the time of initial diagnoses was 96.2 vs 100, 92 vs 97.1, and 100 vs 96%, respectively, for each diagnosis. Re-scintigraphy at the time of the study led to a change in the initial diagnosis of 3/6 cases. Repeated US showed disappearance of previously reported hypoplastic thyroid tissues in eight patients.

CONCLUSION

US alone could not differentiate ectopia and athyreosis, whereas scintigraphy alone is also prone to mistakes in newborns and young ages. Dual thyroid imaging is important for precise structural definition of TD.

IDD Info: a software to manage surveillance data of Iodine Deficiency Disorders

OBJECTIVES

IDD info, a new software for managing survey data of Iodine Deficiency Disorders (IDD), is presented in this paper. IDD Info aims to create IDD project databases, process, analyze various national or regional surveillance data and form final report. It has series measures of choosing database from existing ones, revising it, choosing indicators from pool to establish database and adding indicators to pool. It also provides simple tools to scan one database and compare two databases, to set IDD standard parameters, to analyze data by single indicator and multi-indicators, and finally to form typeset report with content customized.

METHODS

IDD Info was developed using Chinese national IDD surveillance data of 2005. Its validity was evaluated by comparing with survey report given by China CDC.

RESULTS

The IDD Info is a professional analysis tool, which succeeds in speeding IDD data analysis up to about 14.28% with respect to standard reference routines. It consequently enhances analysis performance and user compliance.

CONCLUSIONS

IDD Info is a practical and accurate means of managing the multifarious IDD surveillance data that can be widely used by non-statisticians in national and regional IDD surveillance.

Relationship between urinary iodine and goiter prevalence: results of the Chinese national iodine deficiency disorders survey

BACKGROUND

In 1984, Yu Zhiheng proposed the "U-curve" regularity between urinary iodine (UI) and goiter prevalence (GP). However, along with the adjustment of salt iodine and iodine deficiency disorders (IDD), and surveys followed, some defects were found in the research. As a result, it is time to test and enrich the theory as a series of large sample survey data from China would be helpful.

AIM

To test and enrich the theory of "U-curve" relationship between UI and GP.

SUBJECTS AND METHODS

Based on the Chinese national IDD surveys (1999, 2002, 2005), the High Water Iodine survey of 2005, and the High Risk endemias survey of 2007, this article analyzed the relationship between UI and GP. The UI was grouped according to the World Health Organization (WHO) standard, self-defined (5 microg/l), and Yu Zhiheng's level, separately, the GP was calculated for population with different UI level, the tendency curve was drawn and the fitting curve model was estimated by SPSS.

RESULTS

For the 2005 Chinese national survey and 2005 High Water Iodine survey, we finally got the fitting curves and corresponding UI reference limits.

CONCLUSIONS

The UI and GP formed a "U curve" relationship. It varied with some reasons and fell into an accurate U shape step by step. For High Water Iodine endemias survey, the relationship changed to "power curve". Regarding the WHO recommended GP<5%, the UI range of school-age children in normal district should be 110-315 microg/l, whereas, in high water iodine district should be <80 microg/l.

Loss of integrity of thyroid morphology and function in children born to mothers with inadequately treated Graves' disease

CONTEXT

Central congenital hypothyroidism (CH-C) in neonates born to mothers with inadequately treated Graves' disease usually needs T(4) supplementation. The thyroid and its regulatory system have not yet been extensively studied after T(4) withdrawal, until we observed disintegrated thyroid glands in some patients.

OBJECTIVE

The aim was to study the occurrence and pathogenesis of disintegrated thyroid glands in CH-C patients. DESIGN, SETTING, PATIENTS, PARTICIPANTS: Thyroid function was measured and thyroid ultrasound imaging was performed in 13 children with CH-C due to inadequately treated maternal Graves' disease after T(4)-supplementation withdrawal (group Aa). In addition, thyroid ultrasound imaging was performed in six children with CH-C born to inadequately treated mothers with Graves' disease, in whom T(4) supplementation was not withdrawn yet (group Ab) or never initiated (group Ac), in six euthyroid children born to adequately treated mothers with Graves' disease (group B), and in 10 T(4)-supplemented children with CH-C as part of multiple pituitary hormone deficiency (group C).

MAIN OUTCOME MEASURES

Thyroid function and aspect (volume, echogenicity, echotexture) were measured.

RESULTS

In group A, five children had developed thyroidal hypothyroidism characterized by persistently elevated TSH concentrations and exaggerated TSH responses after TRH stimulation. In the majority of patients in groups A and C, thyroid echogenicity and volume were decreased, and echotexture was inhomogeneous. Thyroid ultrasound imaging was normal in group B children.

CONCLUSIONS

Inadequately treated maternal Graves' disease not only may lead to CH-C but also carries an, until now, unrecognized risk of thyroid disintegration in the offspring as well. We speculate that insufficient TSH secretion due to excessive maternal-fetal thyroid hormone transfer inhibits physiological growth and development of the child's thyroid.