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

High frequency of autoimmune thyroiditis in euthyroid girls with premature adrenarche

Objective

The purpose of this study was to investigate the frequency of autoimmune thyroiditis (AT) among euthyroid prepubertal girls presenting with premature adrenarche (PA). We also aimed to identify the clinical, metabolic, and endocrine profile of girls with AT and concurrent PA and compare them to girls with AT without PA, PA alone and healthy controls.

Methods

Ninety-one prepubertal girls aged 5-10 years, who attended our department for AT, PA and normal variants of growth and puberty were recruited for the study: 73 girls had PA, 6 AT without PA and 12 were referred for investigation of growth. All girls underwent clinical examination, detailed biochemical and hormonal screen. Standard dose Synachten stimulation test (SDSST) and oral glucose tolerance test (OGTT) were performed in all girls with PA. The whole study population was divided in 4 groups: Group PA-/AT+ included 6 girls with AT without PA; Group PA+/AT- PA subjects without AT; Group PA+/AT+ girls with PA and concomitant AT; Group PA-/AT- twelve healthy girls without PA nor AT (controls).

Results

Among 73 girls presenting with PA 19 had AT (26%). BMI, systolic blood pressure (SBP) and the presence of goiter significantly differed between the four groups (p = 0.016, p = 0.022 and p < 0.001, respectively). When comparing hormonal parameters among the four groups significant differences were found in leptin (p = 0.007), TSH (p = 0.044), anti-TPO (p = 0.002), anti-TG (p = 0.044), IGF-BP1 (p = 0.006), Δ4-Α (p = 0.01), DHEA-S (p = <0.001), IGF-1 (p = 0.012) and IGF-BP3 (p = 0.049) levels. TSH levels were significantly higher in Group PA+/AT+ compared to PA+/AT- and PA-/AT- (p = 0.043 and p = 0.016, respectively). Moreover, girls with AT (Groups PA-/AT+ and PA+/AT+) had higher TSH levels than those in Group PA+/AT- (p = 0.025). Girls in Group PA+/AT + showed higher cortisol response at 60 min post-SDSST than girls in Group PA+/AT- (p = 0.035). During the OGTT, insulin concentrations at 60 min were significantly higher in Group PA+/AT + compared to Group PA+/AT- (p = 0.042).

Conclusion

A high frequency of AT among euthyroid prepubertal girls with PA was observed. The combination of PA with AT even in euthyroid state may be associated with a greater degree of insulin resistance, than PA alone.

Anti-thyroid antibodies in the relation to TSH levels and family history of thyroid diseases in young Caucasian women

Background

In young women, hypothyroidism is associated with impaired fertility, increased risk of pregnancy loss, premature delivery, and impaired infant neurodevelopment, justifying the need to recognize the risk of hypothyroidism in women of reproductive age. Thus, this study aimed at assessing the frequency of occurrence of antibodies against thyroid peroxidase (TPOAb) and thyroglobulin (TGAb) in young Caucasian women in connection with various confounders.

Methods

The cross-sectional study involved 366 women aged 18-40 years without a diagnosis of thyroid disease. The personal and family medical history was collected, body mass and height were measured and an ultrasound examination of the thyroid gland was performed. Thyrotropin (TSH), free thyroxine, and free triiodothyronine levels, as well as TPOAb and TGAb titers, were determined by ECLIA.

Results

Two cases of hyperthyroidism (0.5%) and 6 cases (1.6%) of subclinical hypothyroidism were detected. TPOAb was detected in 21 (5.7%) and TGAb in 31 (8.6%) and any of the antibodies in 42 (11.6%) women. Antibodies were more frequent in the subgroup with TSH levels ≥ 2.5 mIU/L than in the subgroup with lower TSH levels (15.5% vs 6.9%, respectively, p<0.05). Any anti-thyroid antibodies were also detected more frequently in the subgroup with TSH levels ≥ 2.5 mIU/L (18.3% vs 10.0%, respectively, p<0.05). Women with the presence of TGAb or seropositive for either TGAb or TPOAb or TPOAb and TGAb antibodies were more likely to have higher TSH levels (OR = 2.48 and OR = 2.02; respectively, p < 0.05 for both). A family history of any thyroid diseases increased the risk of any anti-thyroid antibodies positivity (OR = 1.94; p < 0.05).

Conclusions

The results of our study suggest that TSH ≥ 2.5 mIU/L and a family history of any thyroid diseases justify screening for anti-thyroid antibodies in women of reproductive age, although the occurrence of these antibodies in the majority of cases is not related to thyroid dysfunction.

Children and adolescent patients with goiter and normal thyroid function: US findings related to underlying autoimmune thyroid diseases

This study was conducted to investigate and compare thyroid ultrasonography (US) findings in children and adolescents with goiter and normal thyroid function with positive or negative thyroid autoimmunity. From 2000 to 2020, we reviewed initial thyroid US images in 33 autoimmune thyroid diseases (AITDs) patients and 52 nonAITD patients. Our review of the images focused on thyroid parenchymal hypoechogenicity and heterogeneous echopattern subdivided into 2 groups according to severity: hypoechogenicity 1 and 2 (HO1 and HO2) and heterogeneity 1 and 2 (HE1 and HE2). HO1 and HE1 were observed more frequently in the nonAITD group (86.5% and 42.3%, respectively), while HO2 and HE2 were observed more frequently in the AITDs group (36.4% and 81.8%, respectively). More patients in the AITDs group showed change of both US groups and thyroid function state within the follow-up periods than in nonAITD group (33.3% and 5.77%, respectively). Children and adolescent AITDs patients showed more severe parenchyma hypoechogenicity and heterogeneous echopattern compared with nonAITD patients with goiter and normal thyroid function.

Elevated Thyroid Autoantibodies Aggravate Stroke Severity in Euthyroidism with Acute Ischemic Stroke

Introduction

Studies have indicated that immune reactions contribute to endothelial dysfunction and atherosclerosis. It is unclear whether thyroid dysfunction or elevated thyroid autoantibodies are associated with atherosclerosis. Therefore, we investigated the influence of thyroid autoimmunity related to elevated thyroid autoantibodies on functional outcome in euthyroidism with acute ischemic stroke (AIS).

Methods

All patients with AIS underwent tests for thyroid function and thyroid antibodies (thyroid peroxidase antibody and thyroglobulin autoantibody). We divided the patients suffering from euthyroidism and AIS into positive thyroid autoantibody and negative thyroid autoantibody groups. Demographic profiles, risk factors, and functional outcomes were compared between the two groups.

Results

Out of the total 422 patients, 50 (11.8%) were included in the positive thyroid autoantibody group. The National Institutes of Health Stroke Scale (NIHSS) score at admission and discharge was higher in the positive thyroid autoantibody group than the negative thyroid autoantibody group (P < 0.05). In addition, there was significant difference in the mortality during hospitalizations between the two groups (P < 0.01).

Conclusion

This study showed that thyroid autoantibodies aggravate stroke severity in euthyroidism with AIS. We speculate that vascular damage related to thyroid autoimmunity may aggravate the increased risk of unfavorable outcomes, independent of thyroid function.

Prevalence of autoantibodies in patients with juvenile idiopathic arthritis: results from the German inception cohort ICON-JIA

BACKGROUND

An association of different autoimmune diseases is suspected. In juvenile idiopathic arthritis (JIA), only few and partially conflicting data on the co-existence of other autoimmune disorders are available. The prevalence of autoantibodies in patients with JIA in Germany is not known.

METHODS

Samples from 499 patients (median age at time of blood collection 11 years, median disease duration 4.4 years) in the prospective, multicenter inception cohort of children newly diagnosed with JIA (ICON-JIA) were analysed for the presence of anti-thyroid antibodies, celiac disease-specific antibodies (anti-tTG IgA, anti-tTG IgG), and connective tissue disease-associated antibodies (CTD-screen).

RESULTS

A total of 76 (15.2%) patients had either clinically diagnosed autoimmune comorbidity or elevated autoantibodies. Of 21 patients with clinical autoimmune comorbidity, only 8 were also serologically positive at the time of testing, while 55 patients had autoantibodies without clinical diagnosis. Thus, 63 patients (12.6%) had at least one elevated autoantibody. Antibodies against thyroglobulin were found in 3% and against thyreoperoxidase in 4% of the samples. TSH receptor antibodies could not be detected in any of the 499 patients. Tissue transglutaminase antibodies were elevated in 0.4% of the patients. A positive screen for CTD-specific antinuclear antibodies was found in 7%, but only rarely specific antibodies (anti-dsDNA 1.4%, anti-SS-A and -SS-B 0.2% each, anti-CENP-B 0.4%) were confirmed.

CONCLUSIONS

In our study, a specific correlation between JIA and other autoimmune phenomena could not be confirmed. The lack of well-matched control groups makes interpretation challenging. Further data need to corroborate the suspected increased risk of developing other autoimmune phenomena in JIA patients.

The relationship between ultrasound findings and thyroid function in children and adolescent autoimmune diffuse thyroid diseases

To evaluate the association between thyroid echogenicity and heterogeneity seen on ultrasonography (US) and thyroid function in pediatric and adolescent populations with autoimmune diffuse thyroid diseases (AITD). From 2000 to 2020, we reviewed thyroid ultrasound (US) images and thyroid function statuses in 133 children and adolescent AITD patients. Our review of the images focused on decreased echogenicity and heterogeneity, which were classified into four grades. Among patients with overt hypothyroidism or overt hyperthyroidism, 94.2% (65/69) showed a US grade of 3 or 4. In patients with subclinical hyper/hypothyroidism or euthyroidism, 45.3% (29/64) showed grades 1 or 2. There were no overt hyper/hypothyroidism patients with US grade 1. When we compared US grades according to thyroid status, more severe thyroid dysfunction was significantly associated with higher US grade (p = 0.047). Thyroid stimulating hormone (TSH) level differed significantly according to US grades when we evaluated hyperthyroid (p = 0.035) and hypothyroid (p = 0.027) states independently. 11 patients showed both US grade and thyroid function status changes on follow-up US. In children and adolescent AITD patients, there was an association between decreased echogenicity and heterogeneity on US and thyroid dysfunction.

Chronic Immune Thrombocytopenia and Hashimoto's Hypothyroidism in an Adolescent: Presentation and Implications

Immune thrombocytopenia (ITP) is a disorder characterized by immune-mediated destruction of thrombocytes leading to peripheral blood platelet count of <100 × 10^9/L. Primary ITP is a terminology used in the absence of other causes or disorders that may be associated with thrombocytopenia, i.e., isolated thrombocytopenia. The term secondary ITP is used if such diseases coexist. We present here a case of a 14-year-old female diagnosed with immune thrombocytopenia. When her evaluation was not strongly supportive of primary ITP, she was screened and proved to have a concomitant Hashimoto thyroiditis. Contrary to the popular belief about secondary ITP in adult population, treatment of our patient's hypothyroidism did not improve her platelet's count, and the patient needed multiple immunosuppressive medications to improve her condition.

The Prevalence of Thyroid Autoimmunity in Children with Developmental Dyslexia

Methods

We enrolled pediatric subjects with developmental dyslexia and, as a control group, healthy age- and sex-matched subjects without developmental dyslexia. Thyroid function was evaluated in subjects with developmental dyslexia measuring serum concentrations of thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4). Thyroid autoimmunity was evaluated in all subjects measuring antithyroid peroxidase (TPO-Ab) and antithyroglobulin (TG-Ab) antibodies. In subjects with developmental dyslexia, thyroid ultrasonography (US) was also performed.

Results

We enrolled 51 subjects with developmental dyslexia (M : F = 39 : 12, mean age 12.4 ± 9 years) and 34 controls (M : F = 24 : 10, mean age 10.8 ± 4 years). TPO-Ab positivity was significantly higher in subjects with developmental dyslexia compared to controls (60.8% vs. 2.9%, p < 0.001), while no significant difference was found in TG-Ab positivity (16% vs. 5.8%). Thyroid US performed in 49 subjects with developmental dyslexia revealed a thyroiditis pattern in 60%.

Conclusions

We found an extremely high prevalence of thyroid autoimmunity in children with developmental dyslexia. Further studies are needed to confirm our observations, but our findings may change the approach to this disorder and eventually lead to a systematic determination of thyroid autoimmunity in children with developmental dyslexia.

No Effect of Thyroid Dysfunction and Autoimmunity on Health-Related Quality of Life and Mental Health in Children and Adolescents: Results From a Nationwide Cross-Sectional Study

Background: In adults, a significant impact of thyroid dysfunction and autoimmunity on health-related quality of life (HRQoL) and mental health is described. However, studies in children and adolescents are sparse, underpowered, and findings are ambiguous. Methods: Data from 759 German children and adolescents affected by thyroid disease [subclinical hypothyroidism: 331; subclinical hyperthyroidism: 276; overt hypothyroidism: 20; overt hyperthyroidism: 28; Hashimoto's thyroiditis (HT): 68; thyroid-peroxidase antibody (TPO)-AB positivity without apparent thyroid dysfunction: 61] and 7,293 healthy controls from a nationwide cross-sectional study ("The German Health Interview and Examination Survey for Children and Adolescents") were available. Self-assessed HRQoL (KINDL-R) and mental health (SDQ) were compared for each subgroup with healthy controls by analysis of covariance considering questionnaire-specific confounding factors. Thyroid parameters (TSH, fT4, fT3, TPO-AB levels, thyroid volume as well as urinary iodine excretion) were correlated with KINDL-R and SDQ scores employing multiple regression, likewise accounting for confounding factors. Results: The subsample of participants affected by overt hypothyroidism evidenced impaired mental health in comparison to healthy controls, but SDQ scores were within the normal range of normative data. Moreover, in no other subgroup, HRQoL or mental health were affected by thyroid disorders. Also, there was neither a significant relationship between any single biochemical parameter of thyroid function and HRQoL or mental health, nor did the combined thyroid parameters account for a significant proportion of variance in either outcome measure. Importantly, the present study was sufficiently powered to identify even small effects in children and adolescents affected by HT, subclinical hypothyroidism, and hyperthyroidism. Conclusions: In contrast to findings in adults, and especially in HT, there was no significant impairment of HRQoL or mental health in children and adolescents from the general pediatric population affected by thyroid disease. Moreover, mechanisms proposed to explain impaired mental health in thyroid dysfunction in adults do not pertain to children and adolescents in the present study.

The association between thyroid echogenicity and thyroid function in pediatric and adolescent Hashimoto's thyroiditis

In this study, we evaluated the association between thyroid echogenicity on ultrasonography (US) and thyroid function in pediatric and adolescent Hashimoto's thyroiditis (HT) patients.In 86 pediatric and adolescent HT patients, the association between echogenicity and thyroid function and microsomal autoantibody status was evaluated. Among patients with overt hypothyroidism, 89.2% (33/37) showed a US grade of 3 or 4. All of the patients at grade 4 presented with overt hypothyroidism. In contrast, 97.8% (44/49) of the patients with subclinical hypothyroidism or euthyroidism showed grades 1 or 2. Patients with increased thyroid-stimulating hormone titer also tended to have increased US grades (P < .001). In contrast, free thyroxine levels were significantly decreased with increasing US grade (P < .001).In conclusion, patients with higher US grades had decreased thyroid function (P < .001).

How much of the predisposition to Hashimoto's thyroiditis can be explained based on previously reported associations?

PURPOSE

Our insight in the genetics of Hashimoto's thyroiditis (HT) has become clearer through information provided by genome-wide association studies and candidate gene studies, but remains still not fully understood. Our aim was to assess how many different genetic risk variants contribute to the development of HT.

METHODS

147 HT cases (10.2% men) and 147 controls (13.6% men) were qualified for the analysis. Intrinsic and environmental factors were controlled for. Polymorphisms (SNP) were chosen based on the literature and included markers of the genes PTPN22, CTLA4, TG, TPO among others, and of genomic regions pointed by GWAS studies. SNP were typed on a microarray. Variants in the HLA-DRB1 gene were identified by Sanger sequencing.

RESULTS

Multivariate predisposition to HT was modeled. Based on the investigated group, a model of seven variables was obtained. The variability explained by this model was assessed at only 5.4821% (p = 2 × 10^-6), which indicates that many dozens of factors are required simultaneously to explain HT predisposition.

CONCLUSIONS

We analyzed genetic regions commonly and most significantly associated with autoimmune thyroid disorders in the literature, on a carefully selected cohort. Our results indicated a lack of possibility to predict the risk of HT development, even with a multivariate model. We therefore conclude that strong associations of single genetic regions with HT should be interpreted with great caution. We believe that a change in the attitude towards genetic association analyses of HT predisposition is necessary. Studies including multiple factors simultaneously are needed to unravel the intricacies of genetic associations with HT.

Thyroid function test evolution in children with Hashimoto's thyroiditis is closely conditioned by the biochemical picture at diagnosis

ᅟ

Aim of this commentary is to summarize the salient literature views on the relationships between presentation and evolution patterns of thyroid function in children with Hashimoto’s thyroiditis (HT).

According to the most recent reports, children with HT and subclinical hypothyroidism (SH) are more prone to the risk of developing severe thyroid dysfunctions over time, if compared to those presenting with euthyroidism.

In contrast, children presenting with HT and either overt or subclinical hyperthyroidism are incline to exhibit a definitive resolution of the hyperthyroid phase within some months, although there is a wide variability between the different individuals.

The natural history of frank hypothyroidism in the children with HT has never been investigated so far, since in these cases an immediate onset of replacement treatment is mandatory.

Conclusions

1) a deterioration of thyroid status over time may be observed especially in the children presenting with SH, but also in those presenting with euthyroidism; 2) a definitive resolution of the hyperthyroid phase is generally observed in those presenting with either overt or subclinical hyperthyroidism.

Immune biomarkers in the spectrum of childhood noncommunicable diseases

A biomarker is an accurately and reproducibly quantifiable biological characteristic that provides an objective measure of health status or disease. Benefits of biomarkers include identification of therapeutic targets, monitoring of clinical interventions, and development of personalized (or precision) medicine. Challenges to the use of biomarkers include optimizing sample collection, processing and storage, validation, and often the need for sophisticated laboratory and bioinformatics approaches. Biomarkers offer better understanding of disease processes and should benefit the early detection, treatment, and management of multiple noncommunicable diseases (NCDs). This review will consider the utility of biomarkers in patients with allergic and other immune-mediated diseases in childhood. Typically, biomarkers are used currently to provide mechanistic insight or an objective measure of disease severity, with their future role in risk stratification/disease prediction speculative at best. There are many lessons to be learned from the biomarker strategies used for cancer in which biomarkers are in routine clinical use and industry-wide standardized approaches have been developed. Biomarker discovery and validation in children with disease lag behind those in adults; given the early onset and therefore potential lifelong effect of many NCDs, there should be more studies incorporating cohorts of children. Many pediatric biomarkers are at the discovery stage, with a long path to evaluation and clinical implementation. The ultimate challenge will be optimization of prevention strategies that can be implemented in children identified as being at risk of an NCD through the use of biomarkers.

Thyroid and Islet Autoantibodies Predict Autoimmune Thyroid Disease at Type 1 Diabetes Diagnosis

CONTEXT

Screening of autoimmune thyroid disease in children with type 1 diabetes is important but varies between clinics.

OBJECTIVE

To determine the predictive value of thyroid autoantibodies, thyroid function, islet autoantibodies, and HLA-DQ at diagnosis of type 1 diabetes for autoimmune thyroid disease during follow-up.

SETTING

Forty-three Swedish pediatric endocrinology units.

DESIGN, PATIENTS, AND MAIN OUTCOME MEASURES

At diagnosis of type 1 diabetes, autoantibodies against thyroid peroxidase (TPOAb), thyroglobulin (TGAb), glutamic acid decarboxylase (GADA), insulin, insulinoma-associated protein-2, and 3 variants of zinc transporter 8 (ZnT8W/R/QA) HLA-DQA1-B1 genotypes and thyroid function were analyzed in 2433 children. After 5.1 to 9.5 years, information on thyroxine treatment was gathered from the Swedish National Board of Health and Welfare's Prescribed Drug Register.

RESULTS

Thyroxine was prescribed to 6% of patients. In patients <5 years of age, female sex [hazard ratio (HR) = 4.60; P = 0.008] and GADA (HR = 5.80; P = 0.02) were predictors. In patients 5 to 10 years old, TPOAb (HR = 20.56; P < 0.0001), TGAb (HR = 3.40; P = 0.006), and thyroid-stimulating hormone (TSH) (HR = 3.64; P < 0.001) were predictors, whereas in 10 to 15 year olds, TPOAb (HR = 17.00; P < 0.001) and TSH (HR = 4.11; P < 0.001) predicted thyroxine prescription.

CONCLUSION

In addition to TPOAb and TSH, GADA at diagnosis of type 1 diabetes is important for the prediction of autoimmune thyroid disease in children <5 years of age.

The seroprevalence of antithyroid peroxidase antibodies in bipolar families and bipolar twins: results from two longitudinal studies

Background

Previous studies of our group among bipolar offspring and bipolar twins showed significant higher prevalence’s and levels of antithyroid peroxidase antibodies (TPO-Abs) in offspring and co-twins (without a mood disorder) compared to controls, suggesting that TPO-Abs might be considered as vulnerability factor (trait marker) for BD development.

Objectives

Here we elucidate, in the same cohorts, but now after 12- and 6-year follow-up, whether TPO-abs should be considered as a ‘trait’ marker for BD. The present study aims to investigate whether TPO-Abs (1) are stable over time, (2) are associated with lithium-exposure, (3) share a common genetic background with BD and are related to psychopathology.

Results

In bipolar offspring and twins, the prevalence of TPO-Abs is stable over time (r_s = .72 p < .001 resp. r_s = .82, p < .001) and not associated with lithium use. At follow-up, an increased prevalence of TPO-abs was again observed in bipolar offspring (10,4% versus 4%) and higher TPO-abs titers were still present in co-twins of bipolar cases compared to control twins [mean 1.06 IU/ml (SD .82) versus mean .82 IU/ml (SD .67)], although statistical significance was lost.

Conclusions

Although our results show a trend toward an increased inherited risk of the co-occurrence of BD and thyroid autoimmunity, large-scale studies can only draw final conclusions. Nationwide epidemiological and GWAS studies reach such numbers and support the view of a possible common (autoimmune) etiology of severe mood disorders and chronic recurrent infections and autoimmunity, including thyroid autoimmunity.

The Prevalence, Incidence and Natural Course of Positive Antithyroperoxidase Antibodies in a Population-Based Study: Tehran Thyroid Study

OBJECTIVE

Thyroid peroxidase antibody (TPOAb), the most common antibody frequently measured in population surveys is a protein expressed in the thyroid gland. We conducted the present study to analyze the prevalence and incidence of thyroid auto immunity and natural course of TPOAb in a population based study.

MATERIAL AND METHODS

This prospective study was conducted within the framework of the Tehran Thyroid Study (TTS) on 5783 (2376 men and 3407 women) individuals aged ≥ 20 years who had thyroid function tests at baseline and were followed up for median 9.1 year with TPOAb measurements at approximately every 3 years.

RESULTS

The mean age of total population at baseline was 40.04±14.32. At baseline, of the 5783 participants, 742 (12.8%) were TPOAb positive, with higher prevalence among women than in men (16.0 vs. 8.5%, p = 0.001). The prevalence of TPOAb positivity in the total population was 11.9, 14.9 and 13.6% in the young, middle age and elderly respectively. The total incidence rate (95%CI) of TPOAb positivity in the total population (5020) was 7.1 (6.36-7.98) per 1000 person-years of follow-up, with higher incidence of TPOAb positivity among young participants, i.e. 8.5 (7.5-9.7) per 1000 person-years. Sex specific incidence rate demonstrated that TPOAb positivity was higher in women, 9.3 (8.2-10.7) per 1000 person-years. The Cox's proportional hazard model analysis showed that the hazard ratio of developing TPOAb positivity was higher in women than men (P<0.0001) and tended to increase slightly with serum TSH levels (P<0.0001) but declined with increasing age (P<0.0001) in the total population. Our findings demonstrate that individuals, who became TPOAb positive in each phase, had significant elevation of TSH levels at the phase of seroconversion, compared to baseline values.

CONCLUSION

Gender, age and elevated serum TSH were found to be risk factors for developing TPOAb positivity. Furthermore, compared to baseline a significant elevation of TSH levels during seroconversion phase was observed in TPOAb positive individuals.

Five-Year Prospective Evaluation of Thyroid Function Test Evolution in Children with Hashimoto's Thyroiditis Presenting with Either Euthyroidism or Subclinical Hypothyroidism

BACKGROUND

Whether the course of thyroid function in Hashimoto's thyroiditis (HT) differs in children who present with either euthyroidism or subclinical hypothyroidism (SH) has been incompletely investigated.

AIM

Using a five-year prospective evaluation of 234 children with HT and no prognostic risk factors, this study investigated whether the evolution of the thyroid status is influenced by the biochemical pattern at initial diagnosis.

RESULTS

In the entire series, thyrotropin values significantly increased during follow-up, while free thyroxine values decreased and the proportion of children with a thyroid dysfunction increased from 27.3% to 47.4% (p = 0.0001). An increasing proportion of cases with severe thyroid dysfunction was identified, especially among the 64 patients presenting with SH (group B), but also among the 170 children presenting with euthyroidism (group A) at initial diagnosis. At the end of follow-up, the prevalence of children with overt hypothyroidism was 12.3% in group A compared with 31.2% in group B (p = 0.0007). In the overall population, however, the majority of patients (52.6%) exhibited biochemical euthyroidism at the end of follow-up.

CONCLUSIONS

Children with HT may develop a deterioration of thyroid status during the first five years of disease. Such a trend may be observed, even in the patients who initially present with a mild biochemical picture (either SH or euthyroidism). A total of 57.1% of initially euthyroid children remain euthyroid, and 40.6% of patients with initial SH normalize thyroid function within five years after HT diagnosis. The patients presenting with SH are more prone to the risk of developing severe thyroid dysfunction over time.

Hashimoto's encephalopathy: A rare proteiform disorder

Hashimoto's encephalopathy (HE) is a rare not well understood, progressive and relapsing multiform disease, characterized by seizures, movement disorders, subacute cognitive dysfunction, psychiatric symptoms and responsiveness to steroid therapy. The disorder is generally associated with thyroid diseases and the most common feature is the presence of anti-thyroperoxidase antibodies (TPOAb). Patients are usually euthyroid or mildly hypothyroid at presentation. All age groups can be affected. The pathophysiology is still unclear, especially the link between elevated serum TPOAb and the encephalopathy. Most reported cases occurred in women and girls. Unspecific symptoms, non-pathognomonic laboratory neurophysiology and neuroimaging features make its diagnosis a real challenge for clinicians. The case of a 16 year old boy, with a clinical picture of HE associated with hypothyroidism, demonstrating an excellent response to high dose steroids is presented together with a systematic review of the literature.

Thyroid-related neurological disorders and complications in children

BACKGROUND

Thyroid hormones exert critical roles throughout the body and play an important and permissive role in neuroendocrine, neurological, and neuromuscular function.

METHODS

We performed a PubMed search through June 2014 with search terms including "hypothyroidism," "hyperthyroidism," "neurological complications," "neuropathy," "myopathy," "congenital hypothyroidism," and "encephalopathy." Relevant publications reviewed included case series, individual case reports, systematic reviews, retrospective analyses, and randomized controlled trials. The neurological outcomes of congenital hypothyroidism were reviewed, along with the clinical features of associated neuromuscular syndromes of both hypothyroidism and hyperthyroidism, including other autoimmune conditions. Evidence for, and pathophysiological controversies surrounding, Hashimoto encephalopathy was also reviewed.

RESULTS

The establishment of widespread newborn screening programs has been highly successful in attenuating or preventing early and irreversible neurological harm resulting from congenital thyroid hormone deficiency, but some children continue to display neuromuscular, sensory, and cognitive defects in later life. Acquired disorders of thyroid function such as Hashimoto thyroiditis and Graves' disease are associated with a spectrum of central nervous system and/or neuromuscular dysfunction. However, considerable variation in clinical phenotype is described, and much of our knowledge of the role of thyroid disease in childhood neurological disorders is derived from adult case series.

CONCLUSIONS

Early and aggressive normalization of thyroxine levels in newborn infants with congenital hypothyroidism is important in minimizing neurological sequelae, but maternal thyroid hormone sources are also critically important to the early developing brain. A spectrum of neurological disorders has been reported in older children with acquired thyroid disease, but the frequency with which these occur remains poorly defined in the literature, and much must be extrapolated from adult data. A high index of suspicion for acquired thyroid disease is paramount in the investigation of many neurological disorders of youth, as many reported sequelae of hypothyroidism and hyperthyroidism are reversible with appropriate endocrine management.

Impact of nutritional iodine optimization on rates of thyroid hypoechogenicity and autoimmune thyroiditis: a cross-sectional, comparative study

BACKGROUND

Since several countries have established mandatory food iodine fortification, there has been a decrease in rates of iodine deficiency disorders in parallel with an increase in prevalence of autoimmune thyroid diseases. This study compared the nutritional iodine status and the prevalence of autoimmune thyroiditis and thyroid hypoechogenicity on ultrasound in schoolchildren in São Paulo (Brazil) in two distinct periods of time in which fortified salt had different concentrations of iodine.

METHODS

We conducted a cross-sectional study evaluating 206 children aged 7-14 years and without a history of thyroid disease. Assessments included measurements of thyrotropin (TSH), free thyroxine, antithyroperoxidase (anti-TPO), and antithyroglobulin (anti-TG) antibodies, urinary iodine concentration, and thyroid ultrasound.

RESULTS

Mean urinary iodine concentration was 165.1 μg/L. Eleven children (5.3%) were diagnosed with autoimmune thyroiditis based on at least two of four criteria adopted in our study: positive anti-TPO or anti-TG antibody, hypoechogenicity of the thyroid parenchyma on ultrasound, and a TSH >4.0 μU/mL. Comparing our results with those from a similar study conducted during a period in which concentrations of iodine in the salt were higher (median urinary iodine concentration >300 μg/L), we observed a trend toward a lower prevalence of autoimmune thyroiditis, although no definitive conclusion could be established.

CONCLUSION

The current nutritional iodine status in our cohort was within optimal levels and lower than levels found in 2003. The prevalence of autoimmune thyroiditis seems to be decreasing in parallel with a decrease in iodine intake, although we could not reach a definitive conclusion.

Mechanisms in endocrinology: the crosstalk between thyroid gland and adipose tissue: signal integration in health and disease

Obesity and thyroid diseases are common disorders in the general population and they frequently occur in single individuals. Alongside a chance association, a direct relationship between 'thyroid and obesity' has been hypothesized. Thyroid hormone is an important determinant of energy expenditure and contributes to appetite regulation, while hormones and cytokines from the adipose tissue act on the CNS to inform on the quantity of energy stores. A continuous interaction between the thyroid hormone and regulatory mechanisms localized in adipose tissue and brain is important for human body weight control and maintenance of optimal energy balance. Whether obesity has a pathogenic role in thyroid disease remains largely a matter of investigation. This review highlights the complexity in the identification of thyroid hormone deficiency in obese patients. Regardless of the importance of treating subclinical and overt hypothyroidism, at present there is no evidence to recommend pharmacological correction of the isolated hyperthyrotropinemia often encountered in obese patients. While thyroid hormones are not indicated as anti-obesity drugs, preclinical studies suggest that thyromimetic drugs, by targeting selected receptors, might be useful in the treatment of obesity and dyslipidemia.

Efficacy of homeopathic intervention in subclinical hypothyroidism with or without autoimmune thyroiditis in children: an exploratory randomized control study

INTRODUCTION

The decision to treat subclinical hypothyroidism (SCH) with or without autoimmune thyroiditis (AIT) in children, presents a clinical dilemma. This study was undertaken to evaluate the efficacy of individualized homeopathy in these cases.

METHODS

The study is an exploratory, randomized, placebo controlled, single blind trial. Out of 5059 school children (06-18 years) screened for thyroid disorders, 537 children had SCH/AIT and 194 consented to participate. Based on primary outcome measures (TSH and/or antiTPOab) three major groups were formed: Group A - SCH + AIT (n = 38; high TSH with antiTPOab+), Group B - AIT (n = 47; normal TSH with antiTPOab+) and Group C - SCH (n = 109; only high TSH) and were further randomized to two subgroups-verum and control. Individualized homeopathy or identical placebo was given to respective subgroup. 162 patients completed 18 months of study.

RESULTS

Baseline characteristics were similar in all the subgroups. The post treatment serum TSH (Group A and C) returned to normal limits in 85.94% of verum and 64.29% of controls (p < 0.006), while serum AntiTPOab titers (Group A and B) returned within normal limits in 70.27%of verum and 27.02%controls (p < 0.05). Eight children (10.5%) progressed to overt hypothyroidism (OH) from control group.

CONCLUSION

A statistically significant decline in serum TSH values and antiTPOab titers indicates that the homeopathic intervention has not only the potential to treat SCH with or without antiTPOab but may also prevent progression to OH.

The prevalence of goiter and hypothyroidism among school children 6 years after introduction of a mandatory salt iodination program in a severely iodine-deficient area of the West Black Sea region of Turkey

The objective of the current study was to determine the prevalence and the degree of iodine deficiency after mandatory salt iodization in Yığılca's school-aged children. A total of 806 school children aged 6-19 years were evaluated. The prevalence of goiter in children aged 6-12 and 13-19 years was 20.3 and 23.8%, respectively. The prevalence of hypothyroidism in children aged 6-12 and 13-19 years was 10.4 and 18.9%, respectively. The median serum free tetraiodothyronine (fT4) levels in children aged 6-12 and 13-19-years were 1.16 ng/dL and 0.91 ng/dL, respectively. The median urinary iodine concentration levels in children aged 6-12 and 13-19 years were 83 µg/l and 78 µg/l, respectively. The frequency of autoimmune thyroid disease was 2.1% in Yığılca's SAC. Goiter and iodine deficiency problems remain in rural areas of the West Black Sea Region of Turkey.

Mechanisms of autoimmune thyroid diseases: from genetics to epigenetics

Recent advances in our understanding of genetic-epigenetic interactions have unraveled new mechanisms underlying the etiology of complex autoimmune diseases. Autoimmune thyroid diseases (AITDs) are highly prevalent, affecting 1% to 5% of the population. The major AITDs include Graves disease (GD) and Hashimoto's thyroiditis (HT); although these diseases contrast clinically, their pathogenesis involves shared immunogenetic mechanisms. Genetic data point to the involvement of both shared and unique genes. Among the shared susceptibility genes, HLA-DRβ1-Arg74 (human leukocyte antigen DR containing an arginine at position β74) confers the strongest risk. Recent genome-wide analyses have revealed new putative candidate genes. Epigenetic modulation is emerging as a major mechanism by which environmental factors interact with AITD susceptibility genes. Dissecting the genetic-epigenetic interactions underlying the pathogenesis of AITD is essential to uncover new therapeutic targets.

Thyroid autoimmunity and function among Ugandan children and adolescents with type-1 diabetes mellitus

Introduction

Up to 30% of type-1 diabetes mellitus (T1DM) patients have co-existent thyroid autoimmunity with up to 50% of them having associated thyroid dysfunction. Routine screening for thyroid autoimmunity and dysfunction is recommended in all T1DM patients. However, this was not currently practiced in Ugandan paediatric diabetes clinics. There was also paucity of data regarding thyroid autoimmunity and dysfunction in African children and adolescents with diabetes mellitus. The objective of this study was to quantify the magnitude of thyroid autoimmunity and dysfunction in Ugandan children with TIDM.

Methods

This was a cross sectional descriptive study to determine the prevalence of thyroid autoantibodies and describe thyroid function among children and adolescents aged 1-19 years with diabetes mellitus attending the paediatric diabetes clinic at Mulago National Referral Hospital, Kampala, Uganda. Following enrollment, we obtained details of clinical history and performed physical examination. Blood (plasma) was assayed to determine levels of antibodies to thyroid peroxidase (antiTPO), free thyroxine (FT4) and thyrotropin (TSH).

Results

The prevalence of thyroid autoimmunity was 7.3% (5/69). All antiTPO positive subjects were post pubertal, aged between 13-17 years with females comprising 3/5 of the antiTPO positive subjects. All study subjects were clinically euthyroid; however, 7.3% (5/69) of the study subjects had subclinical hypothyroidism.

Conclusion

These data strengthen the argument for routine screening of all diabetic children and adolescents for thyroid autoimmunity (particularly anti-TPO) as recommended by international guidelines. We also recommend evaluation of thyroid function in diabetic children and adolescents to minimize the risk of undiagnosed thyroid dysfunction.

Serum concentrations of anti-thyroid peroxidase and anti-thyroglobulin antibodies in children and adolescents without apparent thyroid disorders

OBJECTIVE

The age-dependent prevalence and clinical relevance of anti-thyroid peroxidase (TPOAb) and anti-thyroglobulin (TGAb) antibodies in children and adolescents without thyroid diseases are unknown. The aim of this study was to measure the concentration of these thyroid autoantibodies in a large cohort of hospitalized and out-patient subjects. Additionally, we investigated the correlation of TPOAb and TGAb with thyroid parameters as well as with putative confounding parameters such as standard deviation scores (SDS) of height, BMI-SDS and CRP.

METHODS

Serum samples from 841 patients with non-thyroid related diseases between 1 day post partum and 20 years of age were used in a cross-sectional study. TPOAb, TGAb, thyroid parameters (TSH, fT3, fT4 and thyroglobulin) and CRP were measured by the Modular System (Roche, Mannheim).

RESULTS

The values of TPOAb and TGAb showed an age-dependent maximum of antibody frequency for both genders during the first year of life with concentrations of 163 IU/mL and 161 IU/mL in the 95th percentile. In girls, a second maximum was observed during puberty with concentrations of 82 IU/mL TPOAb and 582 IU/mL TGAb in the 95th percentile. Both antibodies correlated significantly (p<0.05) with each other, with fT3, fT4, BMI-SDS (only TPOAb) and CRP and TSH (only TGAb).

CONCLUSION

The prevalence of TPOAb and TGAb was shown to be age-dependent with increased values in the first year of life and during puberty. The increased "physiological" concentrations of TPOAb and TGAb have to be considered when used as diagnostic indicators of autoimmune thyroid disease in a paediatric population.

Elevated thyroid autoantibodies and intracranial stenosis in stroke at an early age

BACKGROUND

Previous studies have shown that hyperthyroidism was related to Moyamoya disease and intracranial artery stenosis. However, it is not clear whether thyroid hormone or thyroid autoantibodies was associated with them.

AIMS AND/OR HYPOTHESIS

Thyroid autoimmunity was previously shown to be associated with Moyamoya disease. Our study aimed to investigate the association between thyroid autoantibodies and intracranial large artery stenosis in young ischemic stroke patients with apparent euthyroid states.

METHODS

We retrospectively reviewed first-onset ischemic stroke patients (age ≤55 years old) consecutively admitted to a single academic center. Intracranial large artery stenosis was defined as ≥50% luminal diameter narrowing. We compared demographic profiles, risk factors (age, hypertension, diabetes, current smoker, atrial fibrillation, hyperlipidemia), thyroid function test, and thyroid autoantibodies including antithyroperoxidase antibody and antithyroglobulin antibody between patients with and without intracranial large artery stenosis. We also performed multivariate logistic regression analysis to evaluate the association between thyroid autoantibodies and intracranial large artery stenosis.

RESULTS

A total of 351 patients were analyzed. The mean age of the patients was 47·0 ± 7·7 (range, 10-55 years), and 252 (71·8%) patients were male. We identified intracranial large artery stenosis in 121 (34·5%) patients. Patients with intracranial large artery stenosis showed a higher frequency of elevated antithyroperpxidase antibody levels in comparison with nonintracranial large artery stenosis group (16·5% vs. 3·9%, P < 0·001). After adjusting for covariates, the presence of elevated antithyroperpxidase antibody levels (odds ratio: 5·318; 95% confidence interval: 2·157-13·110, P < 0·001), age (odds ratio: 1·037; 95% confidence interval: 1·002-1·073, P = 0·039), and atrial fibrillation (odds ratio: 0·091; 95% confidence interval: 0·011-0·756, P = 0·027) was independently associated with intracranial large artery stenosis.

CONCLUSIONS

Thyroid autoantibodies may be associated with the presence of intracranial large artery stenosis in young stroke patients, potentially providing insight on immune pathogenesis of intracranial large artery stenosis.

Hashimoto's encephalopathy: identification and long-term outcome in children

OBJECTIVE

To identify the clinical findings of Hashimoto's encephalopathy (HE) in children and assess their neurological outcome.

METHODS

In this retrospective observational study of 42 children with encephalitis dominated by acute neuro-behavioral features, eight met the diagnostic criteria of HE. Their biological, EEG and brain MRI characteristics were compared to those of the other 34 children. Their clinical outcome was also compared to that of 14 children with Hashimoto's thyroiditis (HT).

RESULTS

All eight HE children were girls and had high levels of anti-thyroid peroxidase (TPO) antibodies at onset (4043.3 ± 2969.8 IU/mL, inclusion criteria: TPO > 60 IU/mL) despite normal T4 and TSH levels in six of them. All HE children had abnormal EEG and brain MRI was abnormal in four of them. Relapses were observed in five children with a second relapse, despite steroid therapy, occurring sooner after the previous episode (median 18 days (range 17-188) vs 213 days (range 14-518)). Immunosuppressive therapy was started in all five children and two developed sequelae by the last follow-up visit (after 4 ± 1.3 years). Mean anti-TPO antibody titers were significantly higher in HE children than in those with Hashimoto's thyroiditis (HT) (4043.3 ± 2969.8 IU/mL vs 1980.9 ± 3449.9 IU/mL, p = 0.03). Four HE children subsequently developed hypothyroidism whereas only one HT patient presented encephalitis.

CONCLUSION

HE is characterized by suggestive clinical symptoms with high levels of anti-TPO antibodies and, in most cases, normal T4 and TSH titers. Despite steroid treatment, relapses and sequelae are frequent. HE may evolve toward HT, but the reverse appears to be rare.

Geographic variations in the frequency of thyroid disorders and thyroid peroxidase antibodies in persons without former thyroid disease within Germany

OBJECTIVE

To investigate regional variations in the frequency of undiagnosed thyroid disorders among 25- to 88-year-old men and women in two communities in the northeast and the south of Germany. In addition, autoantibodies to thyroperoxidase (TPO-Abs) and urinary iodine excretion were determined.

METHODS

Two population-based surveys of men and women using a common standardized protocol, the Study of Health in Pomerania (SHIP) in the northeast of Germany (2505 participants) and the Kooperative Gesundheitsforschung in der Region Augsburg (KORA) in the south of Germany (2316 participants), were compared with regard to the frequency of undiagnosed thyroid disorders.

RESULTS

Compared with the northeast of Germany, urinary iodine excretion and serum thyroid-stimulating hormone (TSH) levels were significantly higher in the south. The median urinary iodine concentration was 110 μg/l (64; 169 μg/l) in SHIP and 151 μg/l (97; 214 μg/l) in KORA, and the median TSH value was 0.81 mIU/l (0.56; 1.15 mIU/l) in SHIP and 1.22 mIU/l (0.84; 1.80 mIU/l) in KORA. The frequency of elevated TSH (TSH ≥ 2.12 mIU/l) was 4.3% in SHIP and 14.1% in KORA (P<0.001); the corresponding values for suppressed TSH (<0.25 mIU/l) were 3.5 and 1.7% (P<0.001). The proportion of ultrasonographic findings was 55.5% in SHIP and 68.0% in KORA. The frequency of serum TPO-Abs did not differ significantly between northeast and south Germany.

CONCLUSIONS

There were considerable regional disparities in the frequency of thyroid disorders within Germany. These differences can be explained not only by different regional histories of natural iodine deficiency but also by current differences in the iodine supply under an identical nationwide iodine fortification program.

Iodine intake and prevalence of thyroid autoimmunity and autoimmune thyroiditis in children and adolescents aged between 1 and 16 years

OBJECTIVES

To determine the status of iodine nutrition in children and adolescents in Almería, Spain. To calculate prevalence of thyroid autoimmunity (TA) and autoimmune thyroiditis (AT) in pediatric ages and to research into associated factors.

METHODS

Cross-sectional epidemiological study. By a multistage probability sampling 1387 children and adolescents aged between 1 and 16 were selected. Physical examination was carried out including neck palpation. Parents were asked about eating habits as well as about social and demographic aspects. Urinary iodine, free thyroxine, TSH, antiperoxidase and antithyroglobulin antibodies were measured. TA was diagnosed when any antibody was positive and AT when autoimmunity was associated with impaired thyroid function or goitre. Results are shown using percentages (and its 95% confidence interval). To study associated factors we used multiple logistic regression, quantifying the relation with odds ratio (OR), and multiple lineal regression.

RESULTS

Median urinary iodine concentration was 199.5 μg/l. The prevalences of TA and AT were 3.7% (2.4-5.0) and 1.4% (0.4-2.4). TA is associated with female sex (OR 2.78; P<0.001) and age (OR 1.30; P<0.001). Iodine status is associated with the intake of milk and dairy product (P<0.001) and vegetable (P=0.021) but not with use of iodized salt at home (P=0.1).

CONCLUSIONS

The iodine supply in children and adolescents in our city is optimal. Milk and dairy products are the most important iodine sources. TA and AT are prevalent in pediatric ages in our city mainly in females and older subjects.

Thyroid status two decades after salt iodization: country-wide data in school children from India

OBJECTIVE

Country-wide evaluation of thyroid disorders in school children following two decades of universal salt iodization (USI) has not been carried out till date. This study was planned with aim to assess thyroid status of school children two decades after the launch of USI programme.

DESIGN

Population survey.

PATIENTS

We collected data from 25 schools in 19 cities across five different geographical zones of India. Those children who were evaluated for anthropometry, and goitre status by palpation formed 'total population'. Children who consented to give blood samples were defined as 'study population'.

MEASUREMENTS

Serum free T3, free T4, TSH, anti-TPO antibody and thyroid ultrasound.

RESULTS

A total of 38,961 children aged 5-15 years formed total population. Goitre rate was 15.5% while thyroid hypoechogenicity was found in 4404 (11.3%) children. In the study population (13,790 children), 2258 (16.4%) had goitre, 505 (3.7%) had positive anti-TPO antibody titres, 1001 (7.3%) had hypothyroidism (TSH > 5.2 μIU/ml) and 41 (0.3%) had thyrotoxicosis (TSH < 0.1 μIU/ml). Among goitrous children, 203 (9.0%) had anti-TPO positivity, 365 (16.1%) had hypoechogenicity of thyroid and either of these were present in 488 (21.6%) children.

CONCLUSIONS

Endemic goitre in school children persisted nationwide, despite more than two decades of USI programme. Thyroid autoimmunity only partially explains the increase in goitre prevalence.

Variable clinical presentation and outcome in pediatric patients with resistance to thyroid hormone (RTH)

Resistance to thyroid hormone (RTH) is characterized by elevated levels of thyroid hormones, normal or slightly increased TSH levels respondent to TRH, resistance to thyroid hormone administration, and variable clinical expression. To describe the diverse clinical and biochemical findings of six children from five unrelated families with molecular diagnosis of RTH (0.5-12.7 years) and their follow-up (3-20 years). All RTH patients and 4 affected parents' harbored mutations in exons 9 or 10 of the thyroid receptor β gene: p.M313T (de novo), pN331D, p.L341P, p.L346F, and p.P453L. At consultation 5/6 had goiter, 4/6 tachycardia, and 3/5 learning disabilities. Median hormone levels were: T(4) 257.4 nmol/l (NR: 77.2-180.2); FreeT(4) 39.9 pmol/(NR:10.3-28.3); T(3) 4.28 nmol/l (NR:1.23-3.39) TSH 2.8 mUI/l (NR: 0.5-5) always responsive to TRH. TSH levels remained detectable after supraphysiologic T(3) administration while SHBG levels showed a paradoxical decrease in 4/6. Thyroid antibodies, initially present in two subjects, became positive in other two during follow-up. All patients grew normally and presented variable symptoms that were treated according to need. Two patients developed psychiatric disorders. Only one of the four affected parents exhibited clinical signs of RTH (tachycardia and depression). Parent's thyroid profile showed similar TSH and T(3) levels but lower T(4) and FT(4) than their children. RTH has a distinctive biochemical profile with highly variable clinical manifestations and outcomes. Its recognition and molecular characterization avoid misleading diagnosis. Treatment has to be instituted according to each subject's own clinical requirements.

Evaluation of thyroid functions with respect to iodine status and TRH test in chronic autoimmune thyroiditis

OBJECTIVE

Chronic autoimmune thyroiditis (CAT) is the most common form of thyroiditis in childhood and a frequent cause of acquired hypothyroidism. The objective of this study was to evaluate the thyroid status of children and adolescents with CAT with respect to iodine status and diagnostic values of thyrotropin-releasing hormone (TRH) test.

METHODS

Seventy-one children (mean age: 11.6 years) were studied in a retrospective analysis. Free thyroxine (T4), thyrotropin (TSH), TSH response to TRH test, thyroid autoantibodies, thyroid sonography, and urinary iodine excretion (UIE) were evaluated.

RESULTS

At diagnosis, 8.5% of patients had overt hypothyroidisim and 36.6% subclinical hypothyroidism; 5.6% had overt hyperthyroidisim and 8.5% had subclinical hyperthyroidism. Of them, 40.8% were euthyroid. Median UIE was 51 mg/L in overt hypothyroidism and 84 mg/L in subclinical hypothyroidism. The values were 316 mg/L and 221 mg/L in overt and subclinical hyperthyroidism, respectively. Basal TSH showed a strong correlation with peak TSH level on TRH test. Thirty-four percent of patients with normal basal TSH level showed an exaggerated TSH response.

CONCLUSION

Iodine deficiency was seen more in cases with hypothyroidism, while excess of iodine was observed to be more frequent in hyperthyroid patients. Iodine status was a strong predictorof the thyroid status in CAT. TRH test may be helpful in further delineating patients with subclinical hypothyroidism.

GADA positivity at onset of type 1 diabetes is a risk factor for the development of autoimmune thyroiditis

AIM

To evaluate whether the presence of diabetes-specific autoantibodies may predict the development of autoimmune thyroiditis (AIT) in children with type 1 diabetes (T1D).

METHODS

Glutamic acid decarboxylase antibodies (GADA), tyrosine phosphatase IA2 antibodies (IA2A), and insulin autoantibodies (IAA) were determined at T1D onset in 341 children and adolescents. Thyroid antibodies (anti-TG, anti-TPO), thyroid stimulating hormone (TSH), T(3) and T(4) were measured in 335 patients at T1D onset and thereafter annually with a follow-up time of 1-15 yr. In case of thyroid antibody positivity and/or TSH elevation, thyroid gland sonography was performed. Treatment with l-thyroxine was started if persistent elevation of TSH and/or thyroid volume was present.

RESULTS

The majority of patients (92.1%) had at least one T1D antibody (71.6% GADA, 73.0% IA2A, and 44.9% IAA). GADA positive patients were older than those without GADA (p < 0.001). Thyroid autoimmunity was found in 15 of 335 patients (4.5%) at T1D onset with female preponderance (p = 0.013). At the end of follow-up, 70 patients (20.9%) had developed thyroid autoantibodies [cumulative incidence (CI) 0.36 ± 0.06 at 10 yr of T1D]. In 30 patients (9.0%), AIT was diagnosed up to 9.4 yr after T1D onset (CI 0.24 ± 0.06 at 10 yr). AIT incidence was not influenced by IAA or IA2A positivity. In multivariate analysis, GADA positive patients were estimated to have a 3.5-fold increased risk of AIT (CI 0.31 ± 0.11 at 10 yr) compared to those without GADA (p = 0.024).

CONCLUSION

Based on the present results, a special focus should be given to GADA positive patients concerning screening for AIT as they are at increased risk to develop autoimmune thyroiditis.

The frequency of Hashimoto thyroiditis in children and the relationship between urinary iodine level and Hashimoto thyroiditis

The aim of this study was to determine the frequency of thyroid autoimmunity in second grade primary school students and to examine the relationship between iodine and Hashimoto thyroiditis (HT). This was a cohort study performed with 1000 students. Urinary iodine levels, antithyroid peroxidase (anti-TPO) and antithyroglobulin (anti-Tg) antibodies were determined in all children. Children with anti-TPO or anti-Tg antibody positivity or with goiter were summoned for detailed examinations. In total, 36 cases (3.6%) were diagnosed as HT. The goiter frequency was found in 17.5% of the whole cohort. Additionally, iodine deficiency was found in 64.2% of all children. The median urinary iodine excretion was determined as 132 microg/L (range 382 microg/L) in the HT group, whereas it was 73 microg/L (range 390 microg/L) in children with goiter but without HT and 81 microg/L (range 394 microg/L) in normal children. The urinary iodine level of HT cases was significantly higher than the other two groups (p < 0.001). HT was also determined in 2% of patients with low urinary iodine levels, in 6.2% of patients with normal urinary iodine levels, and in 7.5% of patients with high urinary iodine levels. Our data demonstrates the close relationship between excessive iodine levels and autoimmunity.

Celiac disease and autoimmune thyroid disease in children with type 1 diabetes mellitus: clinical and HLA-genotyping results

OBJECTIVE

Increased prevalence of celiac disease (CD) and autoimmune thyroid disorders (ATD) in patients with Type 1 diabetes mellitus (T1D) has been widely reported. Such an association may lead to adverse effects on the growth, bone metabolism and fertility, and response to therapy may become difficult. The aim of this study was to evaluate the clinical findings and HLA typing results in patients with T1D associated with CD or ATD.

METHODS

The association of CD and ATD was evaluated in 38 children with T1D aged 1.5-16.8 years who had been followed for 48.3±28 months. Diagnosis of CD was based on positivity for serum endomysial IgA antibody and histopathological findings of intestinal biopsy specimens. Thyroid autoimmunity was assessed by antithyroglobulin and antithyroid peroxidase antibodies and with diagnostic ultrasonographic findings.

RESULTS

ATD was detected in 31.5%, and CD-in 7.8% of T1D patients. Subjects with CD showed either no symptoms or suggestive problems such as short stature, hepatosteatosis, pubertal delay and difficulties in the control of diabetes. Patients with ATD had no clinical symptoms. DQ8 was the most prominent finding in CD.

CONCLUSIONS

It is essential that patients with T1D, regardless of presence or absence of symptoms, should be investigated for CD and ATD.

Autoimmune thyroiditis in antinuclear antibody positive children without rheumatologic disease

BACKGROUND

Children are commonly referred to a pediatric rheumatology center for the laboratory finding of an Anti-nuclear antibody (ANA) of undetermined significance. Previous studies regarding adult rheumatology patients have supported an association between ANA and anti-thyroid antibodies, with the prevalence of thyroid antibodies being significantly higher in patients referred to a rheumatology center for an ANA without evidence of connective tissue disease compared to the general population. The purpose of the present study was to determine the frequency of thyroid antibodies in children referred to a pediatric rheumatology center for a positive ANA without evidence of a connective tissue disease.

METHODS

A retrospective chart review was performed on children who were referred to our pediatric rheumatology center between August 2003 and March 2007 for positive ANA with concurrent thyroid antibody and thyroid function tests performed who did not fulfill criteria for a specific connective tissue disease. Laboratory and clinical features were recorded and analyzed. Mean and standard deviation were used to describe continuous data. Chi-square or Fisher's exact tests were used to compare proportions between variables.

RESULTS

One-hundred and four ANA-positive patients with concurrent thyroid studies were evaluated (88% female, 93% Caucasian, mean age 11.9 +/- 4.0 years). Half of patients had an ANA titer >/= 1:320. The ANA pattern was speckled in 60% of the patients. Thyroid antibodies were detected in 30% of the patients. Anti-Thyroglobulin (ATG) was detected in 29% and Anti-thyroid peroxidase (ATPO) in 21% of the patients; of these children, 14% had hypothyroidism. ANA pattern and titer were not associated with anti-thyroid antibody positivity.

CONCLUSION

Thyroid antibodies associated with chronic lymphocytic thyroiditis, ATG and ATPO, were detected significantly higher in ANA-positive children without a rheumatologic condition (30%) as compared to the general pediatric population (1.3 - 3.4%). ANA titer and pattern did not help predict the presence or absence of thyroid antibodies. Given the high frequency of thyroid antibodies and increased risk of developing hypothyroidism over time, routine evaluation of ATG and ATPO with thyroid function tests in ANA-positive children is recommended.

Thyroid function and thyroid autoimmunity in childhood acute lymphoblastic leukemia off-therapy patients treated only with chemotherapy

OBJECTIVE

Scanty data are available about the thyroid function in childhood acute lymphoblastic leukemia (ALL) off-therapy patients treated only with chemotherapy. We aimed to assess the prevalence of thyroid autoimmunity and thyroid dysfunction in such patients.

DESIGN

Case-control cross-sectional study.

METHODS

Eighty-four patients diagnosed with ALL and treated only with chemotherapy. Mean age at diagnosis 5.9+/-3.6 yr, at recruitment 12.1+/-4.3 yr. The treatment had been stopped 4.3+/-3.2 yr before recruitment. A control group of 60 subjects was recruited. Free T4, TSH, anti-thyroperoxidase, and anti-thyroglobulin antibodies were measured.

RESULTS

Anti-thyroglobulin and anti-thyroperoxidase antibodies were negative in all patients. TSH was increased in 7 patients (8.3%) and 3 controls (5.0%). Free T4 was within the normal limits in all patients and controls.Mean TSH and free T4 levels did not statistically differ between controls and ALL offtherapy patients. TSH was negatively correlated with the age at the diagnosis (p=0.01) and the age at the end of therapy (p=0.008). Anti-thyroglobulin and/or anti-thyroperoxidase antibodies were detected in 3 controls (5%; vs study group: p=0.038), 1 of them with increased TSH.

CONCLUSIONS

Some patients present hyperthyrotropinemia, without anti-thyroid antibodies, with a prevalence comparable to the control group. The thyroid gland seems more prone to be damaged by chemotherapy at a younger age. We think that a thyroid follow- up in ALL off-therapy patients may be advisable and should be differentiated on the basis of the age at the end of treatment, with more frequent tests for younger patients.

The role of thyroid autoantibodies in the etiology of endemic goiter in schoolchildren of Isfahan, Iran

BACKGROUND

Eleven years after the initiation of universal salt iodization program in Iran, the prevalence of goiter is still high in some areas.

AIM

To investigate the role of thyroid autoimmunity in the etiology of residual goiter in schoolchildren of Isfahan, Iran.

MATERIAL AND METHODS

In a cross-sectional study, 2331 schoolchildren were selected by multi-stage random cluster sampling. Thyroid size was estimated in each child by inspection and palpation. Urinary iodine concentration (UIC), serum anti-thyroperoxidase antibody (anti-TPO Ab), and anti-thyroglobulin antibody (Anti-Tg Ab) were measured.

RESULTS

Overall, 32.9% of children had goiter. The median UIC was 1955.5 microg/dl. There was significant difference in prevalence of positive anti-TPO Ab in goitrous (grade 2) and non-goitrous children (9.7 vs 3.7%, p= 0.02). Goitrous children had higher prevalence of positive anti-Tg Ab than non-goitrous ones (15.1 vs 3.1%, p<0.001).

CONCLUSIONS

According to the present study, goiter is still a public health problem in this region. This study suggests that thyroid autoimmunity is among the contributors of goiter persistence after elimination of iodine deficiency in Isfahan.

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.

Turner's syndrome and subclinical autoimmune thyroid disease: a two-year follow-up study

Although autoimmune thyroid disease (AITD) is frequent in Turner's syndrome (TS), followup studies are scant, and there are none regarding subclinical thyroiditis. We investigated thyroid function and morphology in 17 patients with TS (mean age 14.6 years) with transient and asymptomatic variations of TSH and/or thyroid hormones. Our 2-year follow-up included measurements of TSH, free T4, T3 and TPO and Tg antibodies, ultrasound (US) (first and last evaluations) and scintigraphy (first evaluation). Thyroid volume was evaluated relative to the patients' stature. Fourteen had abnormal hormones, including four with hypothyroidism and one with hyperthyroidism, ten had positive antibodies, and all had abnormalities on US; uptake was normal in 14/16. Abnormal hormones were independent of antibodies, number of US findings, age, time of disease and volume. At the end of the follow-up, antibodies were associated with a high number of abnormal US features, particularly heterogeneous texture. Our results indicate that recurring thyroid hormone variations in TS are due to chronic AITD.

Factors for thyroid autoimmunity in children and adolescents with type 1 diabetes mellitus

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is associated with an autoimmune reaction to thyroid antigens including thyroid peroxidase (anti-TPO) and thyroglobulin (anti-Tg).

AIMS

We determined in children with T1DM the relationship of positive anti-thyroid antibodies to potential risk factors, including, age, gender, duration of diabetes, and glutamic acid decarboxylase antibodies (anti-GAD).

MATERIALS AND METHODS

We studied 144 children and adolescents with T1DM. Their age was 12.3 +/- 4.6 (mean +/- SD) years, and duration of diabetes was 4.6 +/- 3.8 years. Anti-thyroid antibodies were determined using a luminescence method and anti-GAD using an enzyme-linked immunosorbent assay.

RESULTS

The prevalence rates of anti-thyroid antibodies among the children with T1DM in our study were: anti-TPO (17.4%), anti-Tg (11.1%), and of both anti-thyroid antibodies (10.4%). The presence of serum anti-thyroid antibodies was positively associated with age (16.6 years in those with positive tests versus 12.0 years in those with negative tests, P = 0.027), duration of diabetes (7.4 versus 4.3 years, P = 0.031), and serum TSH (Thyroid-stimulating hormone) levels (4.8 versus 2.3 microIU/mL, P = 0.002). The presence of both anti-thyroid antibodies was associated with female sex (boys: 4/75 (5.3%), girls: 11/69 (15.9%), chi-square = 6.44, P = 0.04). Subclinical autoimmune thyroiditis (SAIT) was present in 55.5% of the patients with thyroid antibody-positivity and was positively associated with age (16.6 versus 12.0 years, P = 0.001) and diabetes duration (7.6 versus 4.2 years, P = 0.001). Multiple logistic regression analysis revealed that the development of anti-thyroid antibodies was predicted by: 1) the presence of anti-GAD (odds ratio (OR) 1.45, 95% confidence interval (CI) 1.09-1.92), 2) the presence of a second anti-thyroid antibody (OR 134.4, 95% CI 7.7-2350.3), and 3) older age (OR 22.9, 95% CI 1.13-463.2).

CONCLUSIONS

Thyroid autoimmunity was associated with female gender, increasing age, long diabetes duration, the persistence of anti-GAD, and with TSH elevation, indicating subclinical hypothyroidism.

Thyroid autoimmunity in children with features of both type 1 and type 2 diabetes

AIM/HYPOTHESIS

To assess the prevalence of autoimmune thyroid disease (ATD) in insulin-treated youth with clinical features of type 2 diabetes mellitus (T2DM).

METHODS

We evaluated prevalence of thyroid peroxidase (TPO) and thyroglobulin (TGA) antibodies at onset of insulin-treated diabetes and follow-up in 183 White and Black children. Of these, 136 had a body mass index (BMI) <85th percentile with 122 (89%) positive for beta-cell autoimmunity [type 1 diabetes mellitus (T1DM)/group I], 25 were overweight (BMI >or=85 th percentile) with or without acanthosis nigricans with beta-cell autoimmunity ['double' diabetes (DD)/group II], and 22 were overweight with no conventional beta-cell autoantibodies (group III).

RESULTS

The prevalence of TPO and/or TGA was 39 and 29% (p = 0.19) in White and Black children and 39, 32, and 0% (p = 0.007) in groups I, II, and III, respectively. After a median follow-up of 60 months, 3.7, 4.3, and 0% developed hypothyroidism (increased thyroid-stimulating hormone with or without decreased free T4) in groups I, II, and III, respectively (p = 0.6). In subjects with TPO and/or TGA, hypothyroidism developed in 10 and 14% of groups I and II, respectively (p = 0.7). No child without thyroid antibodies developed hypothyroidism.

CONCLUSIONS

In patients with clinical features of T2DM who have evidence of beta-cell autoimmunity (DD), the frequency of thyroid antibodies and ATD is similar to that in classical T1DM. This suggests that TIDM comorbidities may be common in clinical T2DM patients who have beta-cell autoimmunity. Despite their obesity, youth with insulin-requiring diabetes should be screened for thyroid and possibly other T1DM-associated autoimmune diseases.

Thyroid autoimmunity in schoolchildren in an area with long-standing iodine sufficiency: correlation with gender, pubertal stage, and maternal thyroid autoimmunity

BACKGROUND

A strong genetic background and gender are believed to be involved in thyroid autoimmunity (TA). The age these factors become manifest is less clear, however. The objective of the present study was to determine the prevalence of TA in children and adolescents and to determine if there are relationships between the period of onset of TA and gender and between TA and maternal autoimmunity.

METHODS

Antithyroperoxidase antibodies (anti-TPO Ab), antithyroglobulin antibodies (anti-Tg Ab), thyrotropin, thyroxine, triiodothyronine, and urinary iodine were determined in 440 healthy schoolchildren (200 boys and 240 girls), aged 5-18 years, and in 123 mothers living in an iodine-replete region.

RESULTS

The prevalence of positive anti-TPO and anti-Tg Ab was 4.6% and 4.3%, respectively. In girls, the prevalence of positive anti-TPO Ab was higher in Tanner stage II-V compared to Tanner stage I (8.2% vs. 2.2%; p < 0.05). No difference was detected with regard to anti-Tg Ab. In girls, positive anti-TPO and anti-Tg Ab levels were associated with significantly greater thyroid volume. Hypoechogenicity was detected in 52.6% and 36.8% of the children with positive anti-TPO or anti-Tg Ab, respectively (p = 0.0005). The prevalence of autoimmune thyroiditis, as defined by positive serum anti-TPO and/or anti-Tg and an echographic pattern of the thyroid gland having diffuse or irregular hypoechogenicity, was 2.5%. Mothers of anti-TPO Ab positive children had positive anti-TPO Ab more frequently compared to mothers of anti-TPO Ab negative children (82% vs. 18%; p = 0.0005). Mothers of anti-Tg Ab positive children had positive anti-Tg Ab more frequently compared to mothers of anti-Tg Ab negative children (75% vs. 25%; p = 0.0005).

CONCLUSIONS

These findings demonstrate that thyroid antibody positivity in children was significantly associated with maternal autoimmunity and their development in girls emerges at puberty. Since heredity, female gender, and puberty are strongly associated with TA, girls in families with TA should be examined at the onset of puberty.