Peculiarities of autoimmune thyroid diseases in children with Turner or Down syndrome: an overview

Clinical and molecular impact of concurrent thyroid autoimmune disease and thyroid cancer: From the bench to bedside

The recent incorporation of immune checkpoint inhibitors targeting the PD-1 (programmed cell death receptor 1) and CTLA-4 (cytotoxic T lymphocyte antigen 4) pathways into the therapeutic armamentarium of cancer has increased the need to understand the correlation between the immune system, autoimmunity, and malignant neoplasms. Both autoimmune thyroid diseases and thyroid cancer are common clinical conditions. The molecular pathology of autoimmune thyroid diseases is characterized by the important impact of the PD-1/PD-L1 axis, an important inhibitory pathway involved in the regulation of T-cell responses. Insufficient inhibitory pathways may prone the thyroid tissue to a self-destructive immune response that leads to hypothyroidism. On the other hand, the PD-1/PD-L1 axis and other co-inhibitory pathways are the cornerstones of the immune escape mechanisms in thyroid cancer, which is a mechanism through which the immune response fails to recognize and eradicate thyroid tumor cells. This common mechanism raises the idea that thyroid autoimmunity and thyroid cancer may be opposite sides of the same coin, meaning that both conditions share similar molecular signatures. When associated with thyroid autoimmunity, thyroid cancer may have a less aggressive presentation, even though the molecular explanation of this clinical consequence is unclear. More studies are warranted to elucidate the molecular link between thyroid autoimmune disease and thyroid cancer. The prognostic impact that thyroid autoimmune disease, especially chronic lymphocytic thyroiditis, may exert on thyroid cancer raises important insights that can help physicians to better individualize the management of patients with thyroid cancer.

Protein tyrosine phosphatase non-receptor type 22 C1858T gene polymorphism in children with down syndrome and autoimmune thyroid diseases

Autoimmune Thyroid Disease (AIT) is a frequent comorbidity in Down Syndrome (DS). Protein Tyrosine Phosphatase Non- Receptor Type 22 C1858T (PTPN-22 C1858T) gene polymorphisms have a role in the progression of AIT. The study on PTPN- 22 C1858T gene polymorphism as the risk factor of AIT in DS children is still limited. This study aims to evaluate PTPN-22 C1858T polymorphism in Indonesian DS children. A cross-sectional study involving 31 DS children with hypothyroidism (19 boys/12 girls) was conducted for ten months from February to November 2020 at Dr. Soetomo General Hospital Surabaya. The PTPN-22 C1858T gene polymorphism was analyzed using Polymerase Chain Reaction-Restriction-Fragment-Length Polymorphism (PCR-RFLP). Anti-Thyroid Peroxidase (Anti- TPO) and Anti-Thyroglobulin (Anti-TG), FT4, T3, and TSH levels were analyzed using Enzyme-Linked-Immunosorbent-Assay (ELISA). The mean age of the subjects was 19.45±17.3 months. The CT variant of PTPN-22 C1858T was observed in all subjects. The mean level of T3, FT4, and TSH were 1.59±0.45 ng/mL, 0.81±0.57 ng/mL, 0.22±0.21 μU/mL, respectively. Around 83.9% of patients suffered from central hypothyroidism, 12.9% from primary hypothyroidism, and 3.2% from subclinical hypothyroidism. The positive anti-TG and anti-TPO were observed in 96.8% and 58.1%, respectively. CT variant was observed in Indonesian DS children who suffered from hypothyroidism.

Juvenile idiopathic arthritis patients with positive family history of autoimmune thyroid disease might benefit from serological screening: analysis of the international Pharmachild registry

BACKGROUND

Little is known about the association between juvenile idiopathic arthritis (JIA) and autoimmune thyroid disease (AITD) and therefore there are no indications for AITD screening in this population, which is possible using standard blood tests. The objective of this study is to determine the prevalence and predictors of symptomatic AITD in JIA patients from the international Pharmachild registry.

METHODS

Occurrence of AITD was determined from adverse event forms and comorbidity reports. Associated factors and independent predictors for AITD were determined using univariable and multivariable logistic regression analyses.

RESULTS

The prevalence of AITD after a median observation period of 5.5 years was 1.1% (96/8965 patients). Patients who developed AITD were more often female (83.3% vs. 68.0%), RF positive (10.0% vs. 4.3%) and ANA positive (55.7% vs. 41.5%) than patients who did not. AITD patients were furthermore older at JIA onset (median 7.8 years vs. 5.3 years) and had more often polyarthritis (40.6% vs. 30.4%) and a family history of AITD (27.5% vs. 4.8%) compared to non-AITD patients. A family history of AITD (OR = 6.8, 95% CI: 4.1 - 11.1), female sex (OR = 2.2, 95% CI: 1.3 - 4.3), ANA positivity (OR = 2.0, 95% CI: 1.3 - 3.2) and older age at JIA onset (OR = 1.1, 95% CI: 1.1 - 1.2) were independent predictors of AITD on multivariable analysis. Based on our data, 16 female ANA positive JIA patients with a family history of AITD would have to be screened during ±5.5 years using standard blood tests to detect one case of AITD.

CONCLUSIONS

This is the first study to report independent predictor variables for symptomatic AITD in JIA. Female ANA positive JIA patients with positive family history are at increased risk of developing AITD and thus might benefit from yearly serological screening.

A case of Turner's syndrome with Graves' disease and primary hyperparathyroidism

We report a 21-year-old woman with Turner's syndrome, Graves' disease and primary hyperparathyroidism. At 12 years of age, she was of short stature, and was diagnosed with Turner's syndrome and treated with growth hormone. At the age of 17 years, she was diagnosed with Graves' disease. On treatment with methimazole, her laboratory findings normalized. At the age of 20 years, her serum calcium and intact parathyroid hormone levels were high. The upper left parathyroid gland showed swelling and was resected, and adenoma was diagnosed pathologically. Then, primary hyperparathyroidism induced by the adenoma was diagnosed. After the parathyroidectomy, the patient's serum calcium and intact parathyroid hormone levels normalized. Is likely that Turner's syndrome and Graves' disease were not associated with primary hyperparathyroidism. Multiple endocrine neoplasia type 1 was unlikely considering the clinical, laboratory, ultrasonographic, and scintigraphic findings.

Immunological Profile and Autoimmunity in Turner Syndrome

Turner syndrome (TS), characterized by the partial or complete absence of an X-chromosome, provides a unique insight into the role of the X-chromosome and the immune system. While women have a 10-fold higher incidence of autoimmune disease (AD) compared with men, the risk in women with TS is thought to be further doubled. TS is associated with a propensity for a wide variety of ADs that increase in incidence across the life span. Isochromosome Xq as well as isolated Xp deletion karyotypes may predispose to higher rates of AD in TS suggesting the impact of X-chromosome gene dosage. It is likely, however, that epigenetic changes across the genome and the hormonal milieu may also have a profound impact on the immune profile in TS. This review explores the immune phenotype and the spectrum of ADs in TS. Genotype-phenotype correlations are presented with a brief overview of the genetic and hormonal underpinnings.

Graves' disease in a patient with Down syndrome: a shift from hyperthyroidism to hypothyroidism

Down syndrome (DS) is associated with an increased risk of multisystemic dysfunction, namely endocrine abnormalities. Thyroid dysfunction is the most common endocrinological disorder, and it can manifest as either hypothyroidism or hyperthyroidism. A 16-year-old patient with DS developed hyperthyroidism after a lifetime of alternating between subclinical hypothyroidism and euthyroidism. He presented new onset weight loss, agitation and diarrhoea. Laboratory studies were compatible with hyperthyroidism. Thyroid receptor antibodies (TRAbs) were positive, antithyroid peroxidase antibodies and thyroglobulin antibodies were negative. Antithyroid medication (methimazole) was prescribed and, despite therapy adjustments, laboratory evaluation revealed new onset hypothyroidism with persistently positive TRAbs. He experienced weight gain and remained in a hypothyroid state even with withdrawal of methimazole and administration of levothyroxine. This case illustrates an example of Graves' disease with coexisting stimulating and inhibiting TRAbs that led to a shift from hyperthyroidism to hypothyroidism, a rare condition in patients with DS.

Hashimoto's Thyroiditis and Graves' Disease in Genetic Syndromes in Pediatric Age

Autoimmune thyroid diseases (AITDs), including Hashimoto’s thyroiditis (HT) and Graves’ disease (GD), are the most common cause of acquired thyroid disorder during childhood and adolescence. Our purpose was to assess the main features of AITDs when they occur in association with genetic syndromes. We conducted a systematic review of the literature, covering the last 20 years, through MEDLINE via PubMed and EMBASE databases, in order to identify studies focused on the relation between AITDs and genetic syndromes in children and adolescents. From the 1654 references initially identified, 90 articles were selected for our final evaluation. Turner syndrome, Down syndrome, Klinefelter syndrome, neurofibromatosis type 1, Noonan syndrome, 22q11.2 deletion syndrome, Prader–Willi syndrome, Williams syndrome and 18q deletion syndrome were evaluated. Our analysis confirmed that AITDs show peculiar phenotypic patterns when they occur in association with some genetic disorders, especially chromosomopathies. To improve clinical practice and healthcare in children and adolescents with genetic syndromes, an accurate screening and monitoring of thyroid function and autoimmunity should be performed. Furthermore, maintaining adequate thyroid hormone levels is important to avoid aggravating growth and cognitive deficits that are not infrequently present in the syndromes analyzed.

Clinical Characteristics and Follow-Up of 19 Children With Hashimoto's Thyroiditis Aged Below 3 Years: A Single-Center Retrospective Analysis

AIM

To analyze the clinical characteristics of Hashimoto's thyroiditis (HT) in children below 3 years of age in order to improve the understanding of the disease, avoid misdiagnosis, and achieve early diagnosis and treatment.

METHODS

The study retrospectively analyzed the clinical data of 19 patients diagnosed with HT in the first three years of life.

RESULTS

The patients (12 female, 7 male) had an average age of 26.1 ± 8.2 months (range 10-36 months). At presentation, one patient had euthyroidism, ten had hypothyroidism, seven had subclinical hypothyroidism, and one had hyperthyroidism. The most common reasons for doctor's visits were thyroid enlargement (21.1%), global developmental delay (21.1%), and routine thyroid function tests in patients with type 1 diabetes (26.3%). Sixteen patients provided follow-up data, and the mean follow-up time was 23.31 ± 16.44 months (range 1-48 months). In the hypothyroidism group, one patient stopped levothyroxine (LT4) treatment after 2 months; the remaining patients had been treated with LT4 since their diagnosis. In the subclinical hypothyroidism group, one patient whose thyroid function returned to normal after 1 month of being diagnosed was not treated. The remaining patients received LT4 treatment at their diagnosis or during follow-up. The patient with hyperthyroidism was treated with methimazole after diagnosis, but treatment was discontinued 11 months later and LT4 was initiated 26 months after diagnosis. One in four patients with global developmental delay approached normal mental development after LT4 treatment. Four in six patients with short stature achieved height catch-up.

CONCLUSION

At their initial HT diagnosis, most of the children showed hypothyroidism or subclinical hypothyroidism. Children with global developmental delay require continual screening, even if the thyroid function is normal after birth, to determine whether they have HT-induced hypothyroidism. Thyroxine replacement could partially relieve the clinical manifestations of hypothyroidism and early diagnosis and treatment are essential for improving patient prognosis.

Autoimmune thyroid disease and type 1 diabetes mellitus: same pathogenesis; new perspective?

Autoimmune thyroid disease (AITD) and type 1 diabetes mellitus (T1DM) are two common autoimmune diseases that can occur concomitantly. In general, patients with diabetes have a high risk of AITD. It has been proposed that a complex genetic basis together with multiple nongenetic factors make a variable contribution to the pathogenesis of T1DM and AITD. In this paper, we summarize current knowledge in the field regarding potential pathogenic factors of T1DM and AITD, including human leukocyte antigen, autoimmune regulator, lymphoid protein tyrosine phosphatase, forkhead box protein P3, cytotoxic T lymphocyte-associated antigen, infection, vitamin D deficiency, and chemokine (C-X-C motif) ligand. These findings offer an insight into future immunotherapy for autoimmune diseases.

Autoimmune Mechanisms of Interferon Hypersensitivity and Neurodegenerative Diseases: Down Syndrome

Down syndrome (DS), also known as trisomy 21 (T21), is associated with interferon (IFN) hypersensitivity, as well as predilections for Alzheimer's dementia (AD) and various autoimmune diseases. IFN-α and IFN-γ receptors are encoded on chromosome 21 (Ch21). It remains unclear how other Ch21 genes contribute to the neuropathological features of DS/T21. This study tests the hypothesis that identifying IFN-stimulated response element (ISRE) control sites on Ch21 will mark novel candidate genes for DS/T21-related IFN hypersensitivity and neuropathology not previously reported to be associated with IFN functions. We performed whole chromosome searches of online databases. The general ISRE consensus and gamma interferon activation consensus sequences (GAS) were used for identifying IFN-stimulated response elements. Candidate genes were defined as those possessing two or more ISRE and/or GAS control sites within and/or upstream of the transcription start site. A literature search of gene functions was used to select the candidate genes most likely to explain neuropathology associated with IFN hypersensitivity. DOPEY2, TMEM50B, PCBP3, RCAN1, and SIM2 were found to meet the aforementioned gene search and functional criteria. These findings suggest that DOPEY2, TMEM50B, PCBP3, RCAN1, and SIM2 are genes which may be dysregulated in DS/T21 and may therefore serve as novel targets for treatments aimed at ameliorating the neuropathological features of DS/T21. Future studies should determine whether these genes are dysregulated in patients with DS, DS-related AD, and autoimmune diseases.

Clinical case report: A case of Turner syndrome with Graves' disease

INTRODUCTION

The incidence of Hashimoto's thyroiditis among patients who have Turner syndrome (TS) has increased, but Graves' disease (GD) in patients with TS is rarely reported. Here we report a rare case of TS with GD accompanied by hypogonadotropic hypogonadism.

PATIENT CONCERNS

We report the case of a 16-year-old girl who complained nervousness, fatigue, marasmus, heat intolerance, sweating, palpitation, and tremor lasting for more than a month. She had no medical history.

DIAGNOSIS

TS was diagnosed of the results of karyotyping demonstrated a gene karyotype of 46, X, i (X)(q10). GD was also diagnosed in this patient following the detection of thyroid function analysis.

INTERVENTIONS

Methimazole was administered after identification of GD. Due to the absence of secondary sex characteristics, the patient was given a conjugated estrogen preparation for 1 year, followed by the addition of estradiol cyproterone tablets for the onset of menstruation.

OUTCOMES

The hyperthyroidism symptoms of the patient had improved both clinically and laboratory tests after methimazole therapy. She was treated with estrogen and estradiol cyproterone, and the uterus and secondary sexual characteristics of the patient developed during 1 year follow-up.

CONCLUSION

TS generally presents as hypergonadotropic hypogonadism. However, hypogonadotropic hypogonadism cannot completely exclude TS. The diagnosis of this disease depends on chromosomal examination. The disease should be detected and treated as early as possible to improve life quality of the patient.

Autoimmune Thyroid Disease in Specific Genetic Syndromes in Childhood and Adolescence

Autoimmune thyroid disease (ATD) is the most frequent cause of acquired thyroid dysfunction, most commonly presenting either as Hashimoto's thyroiditis or Graves' Disease. Hashimoto's thyroiditis is characterized by the presence of thyroid-specific autoantibodies, more commonly anti-thyroperoxidase antibodies in the serum and the typical inhomogeneous echostructure of the thyroid on a thyroid ultrasound examination. Hashimoto's thyroiditis can for a long time be accompanied by normal thyroid function and hypothyroidism can only progressively be established. Graves' disease is much less frequent in childhood and adolescence and presents with overt hyperthyroidism. After the onset of puberty, ATD affects females with a higher incidence than males, while during the prepubertal period there is not such a clear preponderance of affected females. ATD can occur either isolated or in the context of other autoimmune disorders, such as type 1 Diabetes mellitus (T1D), celiac disease, alopecia areata, vitiligo, etc. Especially at the pediatric age, a higher incidence of ATD is also observed in the context of specific genetic syndromes, such as trisomy 21 (Down syndrome), Klinefelter syndrome, Turner syndrome, or 22q11.2 deletion syndrome. Nevertheless, although thyroid dysfunction may also be observed in other genetic syndromes, such as Prader-Willi or Williams syndrome, the thyroid dysfunction in these syndromes is not the result of thyroid autoimmunity. Interestingly, there is emerging evidence supporting a possible link between autoimmunity and RASopathies. In this review article the incidence, as well as the clinical manifestation and accompanied pathologies of ATD in specific genetic syndromes will be presented and regular follow-up for the early identification of the disorder will be proposed.

Down syndrome with primary thyroid diffuse large B-cell lymphoma and Hashimoto thyroiditis: A CARE compliant case report

RATIONALE

Adult patients with Down syndrome (DS) commonly develop Hashimoto thyroiditis (HT). However, primary diffuse large B-cell lymphoma (DLBCL) of the thyroid is uncommon, and its simultaneous occurrence with HT is very rare. To our knowledge, coexisting DLBCL and HT in a patient with DS has not been reported in the medical literature.

PATIENT CONCERNS

We present a 43-year-old woman with DS who reported progressive swelling of the neck on the right side and dyspnea over the previous 1 month, with associated neck ache, hoarseness, and dysphagia. Thyroid ultrasonography and computed tomography of the neck revealed a large mass in the right lobe compressing the surrounding tissues.

DIAGNOSES

Based on the clinical and histopathologic findings, the patient was diagnosed with coexisting primary thyroid DLBCL and HT.

INTERVENTIONS

A palliative unilateral thyroidectomy was performed; postoperative histopathology and immunohistochemistry revealed thyroid DLBCL and HT. The patient was scheduled for chemotherapy and targeted therapy after recovering from surgery.

OUTCOMES

The patient died 3 weeks after surgery due to asphyxia caused by uncontrollable growth of recurrent tumor.

LESSONS

The coexistence of DS, primary thyroid DLBCL, and HT is very rare. There is no standardized approach to the clinical identification of primary thyroid lymphoma (PTL), making early diagnosis difficult. A multidisciplinary approach and close follow-up are needed. The mechanisms of the link between DS and PTL are poorly understood and remain to be elucidated.

How can we make pregnancy safe for women with Turner syndrome?

Pregnancy is a crucial issue in patients with Turner syndrome (TS). Although natural pregnancies have been reported in 4-7% of TS patients, most women will need assisted reproductive technologies (ART) with oocyte donation. The main issue is the maternal mortality rate that is higher than in the general population. It is related to cardiovascular anomalies and particularly aortic dissection. TS, per se, is not a contraindication for pregnancy, but a multidisciplinary screening is mandatory before initiating a pregnancy. It includes repeated aortic diameters evaluation, blood pressure measurement and biological testing evaluating thyroid and liver functions, as well as blood glucose level. In order to make the pregnancy safe, contraindications of pregnancy should be respected and identification of high-risk patients for cardiovascular events should be performed. Hypertension and pre-eclampsia prevention may benefit from beta-blockers and aspirin, respectively. Collaborations between endocrinologists, cardiologists, and obstetricians are mandatory during pregnancy and even in the postpartum period. Counseling the patients about the risks of pregnancy, screening them and spreading the international guidelines to physicians taking care of patients with TS are the three pillars of a safe pregnancy.

Role of antithyroid autoimmunity as a predictive biomarker of chronic immune thrombocytopenia

BACKGROUND

Immune thrombocytopenia (ITP) is an acquired immune-mediated disorder characterized by isolated thrombocytopenia. Pediatric ITP patients are prone to develop autoantibodies such as antithyroglobulin (TG) and antithyroperoxidase (TPO), even in the absence of clinical signs of autoimmune disease. The aim of this multicenter retrospective study was to evaluate (1) the prevalence of positivity of antithyroid antibodies (TPO and TG) in a large cohort of pediatric patients with chronic ITP; (2) the role of autoimmune thyroiditis as a prognostic factor for chronicity of ITP.

PROCEDURE

For this retrospective study, we collected data from patients diagnosed as affected by chronic ITP between 2011 and 2014 in six centers belonging to the Italian Association of Pediatric Haematology and Oncology (AIEOP).

RESULTS

From the analysis of data, we found a significantly higher prevalence of antithyroid antibodies in children with chronic ITP (11.6%) than in the pediatric population (1.2%-1.3%). No correlation has been found between the platelet count and the prevalence of positive antithyroid antibodies at any detection time of the study.

CONCLUSIONS

The results of our study demonstrated that (1) the prevalence of positivity for antithyroid antibodies (anti-TPO and anti-TG) in pediatric patients with chronic ITP results is significantly higher than in the pediatric population; (2) autoimmune thyroiditis does not seem to play a role as a prognostic factor for chronicity of ITP in pediatric patients.

Phenotypic Expression of Autoimmunity in Children With Autoimmune Thyroid Disorders

Autoimmune thyroid diseases (AITDs), including Hashimoto's thyroiditis (HT) and Graves' disease (GD), tend to aggregate with other non-thyroidal autoimmune diseases (NTADs). Aim of this Mini-review is to report the most recent insights concerning the clustering of NTADs in pediatric patients with either HT or GD, the pathophysiology of AITDs and the metamorphic thyroid autoimmunity. A systematic literature research of the last 15 years, according to EQUATOR statement, was carried out through MEDLINE via PubMed (http://www.ncbi.nlm.nih.gov/pubmed/) Embase, CINAHL, Cochrane Library, based on the following keywords: (autoimmune thyroid disease OR Hashimoto thyroiditis OR Grave's disease) AND (autoimmune comorbidities OR extra-thyroidal autoimmune disorders) AND (children OR adolescents OR pediatrics) AND (celiac disease OR type 1 diabetes mellitus OR arthropathies OR cutaneous diseases) AND (Turner syndrome OR Down syndrome). One-hundred and twenty-eight manuscripts were extrapolated but only seventeen were eligible. On the basis of the available reports it may be inferred that clustering of NTADs can be significantly modified by both patients' age at AITDs presentation and association with Down's syndrome (DS). Particularly, the association of AITDs with celiac disease and type 1 diabetes was most commonly reported in children than in adults. A sequential shifting from HT to GD has been described in children with AITDs, and it seems to be more frequent in children with DS than in those without DS. Coexistence of autoimmune diseases might be the result of a complex interaction among genetics, environment and epigenetic modifications that are able to affect gene expression, immune system response and, finally, the pathogenesis of autoimmune diseases.

Prevalence of autoimmune thyroid diseases among the Turner Syndrome patients: meta-analysis of cross sectional studies

Objective

This meta-analysis was done to estimate the prevalence of autoimmune thyroid diseases (ATDs) in Turner Syndrome patients, and to determine the clinical status of thyroid autoimmune diseases that occur frequently in association with Turner Syndrome.

Results

A total of 18 studies were included in the meta-analysis. The pooled overall prevalence of autoimmune thyroid diseases in Turner Syndrome patients was 38.6% (95% CI 29.7–47.6%), with 12.7% (95% CI 9.30–16.1%) of them had clinical hypothyroidism and 2.6% (95% CI 1.5–3.8%) had hyperthyroidism. I-squared test had a high result of heterogeneity. In subgroup analyses, the prevalence of ATDs was higher in the European region than Asian region. Autoimmune thyroid diseases are commonly associated with Turner Syndrome. Early detection of thyroid diseases by optimal screening among children with Turner Syndrome is required to ensure effective management.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3950-0) contains supplementary material, which is available to authorized users.

Advances in pediatrics in 2017: current practices and challenges in allergy, endocrinology, gastroenterology, genetics, immunology, infectious diseases, neonatology, nephrology, neurology, pulmonology from the perspective of Italian Journal of Pediatrics

This review provides an overview of a remarkable number of significant studies in pediatrics that have been published over the past year in the Italian Journal of Pediatrics. We have selected information from papers presented in the Journal that deal with allergy, endocrinology, gastroenterology, genetics, immunology, infectious diseases, neonatology, nephrology, neurology, pulmonology. The relevant epidemiologic findings, and developments in prevention, diagnosis and treatment of the last year have been discussed and placed in context. We think that advances achieved in 2017 will help readers to make the future of patients better.

Thyroid Disorders in Subjects with Down Syndrome: An Update

Down syndrome (DS) is the commonest chromosomal disorder among live born infants. DS is associated with increased risk of endocrine abnormalities particularly thyroid gland disorders. The spectrum of thyroid dysfunction in patients with DS include congenital hypothyroidism, subclinical hypothyroidism, acquired hypothyroidism (autoimmune - non autoimmune), and hyperthyroidism. This review will focus on the characteristics of the different presentations of thyroid abnormalities in DS, screening and management recommendations. (www.actabiomedica.it)

Thyroid Disorders in Subjects with Down Syndrome: An Update

Down syndrome (DS) is the commonest chromosomal disorder among live born infants. DS is associated with increased risk of endocrine abnormalities particularly thyroid gland disorders. The spectrum of thyroid dysfunction in patients with DS include congenital hypothyroidism, subclinical hypothyroidism, acquired hypothyroidism (autoimmune - non autoimmune), and hyperthyroidism. This review will focus on the characteristics of the different presentations of thyroid abnormalities in DS, screening and management recommendations.

Epidemiological and clinical aspects of autoimmune thyroid diseases in children with Down's syndrome

Aim of this commentary is to report the main peculiarities that have been found to characterize the phenotypic expression of autoimmune thyroid diseases (AITDs) in children with Down's syndrome (DS). According to recent reports, DS children are, per se, more exposed to the risk of both Hashimoto's thyroiditis (HT) and Graves' disease (GD), irrespective of other concomitant risk factors, such as female gender and family antecedents for AITDs. In the context of extra-thyroidal autoimmune disorders, the ones that preferentially aggregate with AITDs in DS children are alopecia areata and vitiligo. Another peculiar aspect, in DS children, is that HT presents with a more severe biochemical picture, which furtherly deteriorates over time. By contrast, GD does not demonstrate a more severe clinical and biochemical picture with respect to that generally observed in patients without DS. Finally, DS children might be at higher risk of progressing from HT toward GD over time.

Subclinical hypothyroidism in children: is it always subclinical?

Aim of this commentary is to report current knowledges on the main clinical and metabolic abnormalities which might be observed in children with longstanding and untreated subclinical hypothyroidism (SH) and to comment the most recent views about natural evolution of thyroid function in the cases with either idiopathic or Hashimoto’s thyroiditis-related SH. On the basis of these preliminary remarks, the essential guidelines for an appropriate and tailored management of SH children are also proposed.

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.

Immunological Profile and Predisposition to Autoimmunity in Girls With Turner Syndrome

OBJECTIVE

The risk of autoimmune diseases (AD) in patients with Turner Syndrome (TS) is twice higher than in the general female population and four times higher than in the male population. The causes of the increased incidence of AD in TS are still under discussion. We hypothesized the presence of a specific humoral, cellular, and regulatory T cell (Treg) immunity profile which predisposes to AD, disorders of immunity, and disorders of immune regulation.

METHODS

The study encompassed 37 girls with TS and with no signs of infection. The control group included 11 healthy girls with no hormonal disorders. A medical history focused on AD and immunity disorders was taken from all participants. The levels of: immunoglobulins IgG, IgA, IgM, total lymphocytes, lymphocytes subpopulations CD3+, CD4+, CD8+, CD19+, natural killer cells, Treg cells (CD4+ CD25+ CD127- FOXP3+), anti-inflammatory cytokines (interleukin-10, transforming growth factor-β), anti-nuclear antibodies, glutamic acid decarboxylase (GAD65 Abs), anti-thyroid peroxidase (anti-TPO Ab), and anti-thyroglobulin (anti-TG Ab) autoantibodies were determined in each participant.

RESULTS

The mean age and BMI in the TS group and in controls were comparable (11.9 ± 4.1 vs. 12.5 ± 4.0 years; 19.2 ± 3.4 vs. 19.7 ± 4.6, p > 0.05). Mean hSDS was significantly higher in controls (-2.2 ± 0.9 vs. -0.4 ± 1.5, p < 0.0001). AD and recurrent otitis media with complications were previously confirmed in 9 (24.3%) and 10 (27.0%) girls with TS. The TS group had significantly lower levels of IgG (p = 0.02), lower%CD4 (p < 0.001) and a significantly lower CD4:CD8 ratio than the controls (p < 0.001). There were no differences in mean Treg% between girls with TS and healthy controls. However, comparing Treg% between the TS group with coexisting autoimmunity and the remaining participants, a statistically significant difference was observed (2.09 ± 0.5 vs. 2.77 ± 1.6, p = 0.048). Patients with iXq had lower CD4% and more frequently had positive anti-TPO Ab and anti-TG Ab compared to the remaining girls with TS and controls (p = 0.001, p < 0.001, p = 0.01).

CONCLUSION

TS predisposes to AD, especially if associated with coexisting iXq. Our preliminary findings show that patients with TS may present a specific profile of humoral and cellular immunity markers, different from healthy girls.

Are Perinatal Events Risk Factors for Childhood Thyroid Autoimmunity?

BACKGROUND

Environmental and genetic factors possibly trigger thyroid autoimmunity. Studies on perinatal risk factors for childhood thyroid autoimmunity are sparse.

OBJECTIVES

The aim was to investigate if perinatal factors, family history of autoimmune diseases, and HLA-DQ genotypes contribute to thyroid autoimmunity in the Diabetes Prediction in Skåne (DiPiS) study.

METHODS

Samples from 1,874 ten-year-old children were analyzed for autoantibodies to thyroid peroxidase (TPOAb), thyroglobulin (TGAb), and HLA-DQ genotypes. Information on perinatal events and family history of autoimmunity was gathered prospectively in questionnaires.

RESULTS

Thyroid autoimmunity was found in 6.9% of the children (TPOAb 4.4%, TGAb 5.8%, both autoantibodies 3.3%) and was overrepresented in girls. Prematurity was positively related to TGAb (OR: 2.4, p = 0.003, p_c = 0.021). Autoimmune diseases in the family increased the risk of thyroid autoimmunity: TPOAb (OR: 2.2, p = 0.012), any autoantibody (OR: 1.7, p = 0.04), and both autoantibodies (OR: 2.2, p = 0.024). A first-degree relative (FDR) with thyroid disease increased the risk for TPOAb (OR: 2.4, p = 0.03) and both autoantibodies (OR: 2.6, p = 0.03), a FDR or sibling with celiac disease increased the risk for both autoantibodies (OR: 3.7, p = 0.03, and OR: 4.8, p = 0.003), a FDR or sibling with diabetes increased the risk for thyroid autoantibody (OR: 3.0, p = 0.01, and OR: 5.4, p = 0.032), and a father with rheumatic disease increased the risk for TPOAb (OR: 15.2, p = 0.017), TGAb (OR: 11.3, p = 0.029), any autoantibody (OR: 9.6, p = 0.038), and both autoantibodies (OR: 20, p = 0.01).

CONCLUSIONS

Thyroid autoimmunity was found in 6.9% of the 10-year-old children who were being followed for their risk of type 1 diabetes. No relation to perinatal factors was found, with the exception of a possible association between prematurity and TGAb. Family history of autoimmune diseases increased the risk of thyroid autoimmunity.

Is Graves' disease a primary immunodeficiency? New immunological perspectives on an endocrine disease

BACKGROUND

Uncertainty about factors influencing the susceptibility and triggers for Graves' disease persists, along with a wide variation in the response to anti-thyroid drugs, currently at approximately 50% of non-responders. The aim of this narrative review is to summarize immunological concepts, with a combined endocrine and immunological perspective, to highlight potential new areas of research.

MAIN TEXT

Relevant studies were identified through a systematic literature search using the PubMed and EMBASE databases in March 2016. No cut-offs regarding dates were imposed. We used the terms "Graves' Disease" or "Basedow" or "thyrotoxicosis" together with the terms "etiology", "pathophysiology", "immunodeficiency", "causality", and "autoimmunity". The terms "orbitopathy", "ophthalmopathy", and "amiodarone" were excluded. Articles in English, French, German, Croatian, Spanish, and Italian were eligible for inclusion.

CONCLUSIONS

While concepts such as the impact of iodine, smoking, human leucocyte antigen, infections, and ethnicity are established, new ideas have emerged. Pertaining evidence suggests the involvement of autoimmunity and immunodeficiency in the pathophysiology of Graves' disease. Recent studies point to specific immunological mechanisms triggering the onset of disease, which may also serve as targets for more specific therapies.

Clinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting

Turner syndrome affects 25-50 per 100,000 females and can involve multiple organs through all stages of life, necessitating multidisciplinary approach to care. Previous guidelines have highlighted this, but numerous important advances have been noted recently. These advances cover all specialty fields involved in the care of girls and women with TS. This paper is based on an international effort that started with exploratory meetings in 2014 in both Europe and the USA, and culminated with a Consensus Meeting held in Cincinnati, Ohio, USA in July 2016. Prior to this meeting, five groups each addressed important areas in TS care: 1) diagnostic and genetic issues, 2) growth and development during childhood and adolescence, 3) congenital and acquired cardiovascular disease, 4) transition and adult care, and 5) other comorbidities and neurocognitive issues. These groups produced proposals for the present guidelines. Additionally, four pertinent questions were submitted for formal GRADE (Grading of Recommendations, Assessment, Development and Evaluation) evaluation with a separate systematic review of the literature. These four questions related to the efficacy and most optimal treatment of short stature, infertility, hypertension, and hormonal replacement therapy. The guidelines project was initiated by the European Society for Endocrinology and the Pediatric Endocrine Society, in collaboration with The European Society for Pediatric Endocrinology, The Endocrine Society, European Society of Human Reproduction and Embryology, The American Heart Association, The Society for Endocrinology, and the European Society of Cardiology. The guideline has been formally endorsed by the European Society for Endocrinology, the Pediatric Endocrine Society, the European Society for Pediatric Endocrinology, the European Society of Human Reproduction and Embryology and the Endocrine Society. Advocacy groups appointed representatives who participated in pre-meeting discussions and in the consensus meeting.

Thyroid dysfunction in patients with Down syndrome: Results from a multi-institutional registry study

The goals of this undertaking were to assess the outcomes of thyroid screening tests and adherence to thyroid screening guidelines across five Down syndrome (DS) specialty clinics in various states. Data related to thyroid screening were collected for 663 individuals across five clinics specializing in the comprehensive care of individuals with DS for a period of 1 year. Of the 663 participants, 47.7% of participants had a TSH and free T4 ordered at their DS specialty clinic visit. Approximately 19.0% (60/316) had a new thyroid disorder diagnosis made. We conclude that a sizable proportion of the patients with DS are not up-to-date on current guidelines when they present to a DS specialty clinic, while adherence to thyroid screening guidelines helps facilitate early diagnoses. Hypothyroidism is prevalent in the population, consistent with reported literature. DS specialty clinics can help patients stay current on screening guidelines.

Autoimmune thyroid diseases in children

Autoimmune thyroid diseases (AIT) are common in children and may present with a variety of signs and symptoms including: euthyroid goiter, hypothyroidism, or hyperthyroidism. The natural history of AIT may be different in children but in all age groups, there appear to be genetic risk factors and environmental triggers that initiate thyroid autoimmunity. Areas covered: In this review, we summarize recent studies that investigate the genetics and environmental triggers believed to be involved in thyroid autoimmunity. We also discuss the approach and controversies in the treatment of children with AIT. Expert commentary: Much has been learned about the major roles for genetics, cytokines, regulatory lymphocytes, and environmental triggers in CLT but controversies remain.

Analysis of the factors affecting the evolution over time of subclinical hypothyroidism in children

Aim of this commentary is to report the most recent views about natural history of subclinical hypothyroidism (SH) according to the different etiologies. In children with idiopathic SH the natural evolution is often favourable, with a high percentage of cases reverting to euthyroidism or remaining SH even after a prolonged follow-up. By contrast, the risk of a significant deterioration of thyroid status is distinctly higher in the SH children with Hashimoto’s thyroiditis (HT). This risk is even higher in the cases with both HT-related SH and chromosomal abnormalities, such as Turner or Down’s syndrome.

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.

In children with autoimmune thyroid diseases the association with Down syndrome can modify the clustering of extra-thyroidal autoimmune disorders

BACKGROUND

It is known that the association with Down syndrome (DS) can affect the phenotypic expression of autoimmune thyroid diseases (AITDs), whilst is unknown whether the clustering of extra-thyroidal autoimmune diseases (ETADs) may also be atypical in DS children.

METHODS

The aim of this study was to investigate the clustering of ETADs in 832 children with AITDs divided in two groups with or without DS (A and B, respectively) and in four subgroups of patients aged either <6 or ≥6 years.

RESULTS

The rate of children with ETADs was significantly higher in Group A; in particular, alopecia areata (p=0.00001) and vitiligo (p=0.00001) were found more often in Group A irrespective of age, whilst the distribution of T1 diabetes mellitus was not different in the two groups. Celiac disease prevalence was significantly higher in DS patients only in the older subgroup.

CONCLUSIONS

The association with DS may be able to modify the clustering of ETADs in the children with AITDs by favoring the aggregation of some specific diseases such as alopecia areata and vitiligo.

Management of hyperthyroidism in children

Treatment of hyperthyroidism in children differs according to its etiology; in particular, the optimal therapy of Graves' disease (GD) remains a matter of debate and there is currently no evidence-based therapeutic strategy that is universally adopted in all the countries. Areas covered: The most recent treatment strategies in the different pediatric conditions which may be associated with hyperthyroidism. We searched PubMed and Cochrane (1990 to 2016) in order to identify articles to include in this review using the following terms: Hyperthyroidism, Childhood, Antithyroid drug therapy, Thyroidectomy, Radioactive iodine. Expert commentary: Although pharmacological therapy represents the first-line approach for GD children, we recommend to individualize, as much as possible, the overall therapeutic approach, with no prejudices towards radical therapies, particularly in the cases with frequent relapses. Clinical and laboratory preferential criteria for an individualized therapeutic approach to GD children are given. Treatment procedures for hyperthyroid children without GD are also discussed.

Metamorphic thyroid autoimmunity in Down Syndrome: from Hashimoto's thyroiditis to Graves' disease and beyond

BACKGROUND

It is known that Hashimoto's thyroiditis (HT) may progress to Graves' disease (GD) and that this phenomenon may be more frequent in the patients with Down syndrome (DS).

AIMS

To shed light on the relationships between Down syndrome (DS) and metamorphic thyroid autoimmunity.

PATIENTS AND METHODS

We reconstructed the conversion process from HT to GD in 12 DS children. All the data recorded at HT diagnosis and throughout the time interval from entry to GD presentation were retrospectively taken from patients' files, as well as those recorded at GD diagnosis and during the subsequent evolution. From GD diagnosis all patients underwent methimazole treatment, at a dose that was adjusted on the basis of clinical findings and thyroid tests.

RESULTS

Time interval between HT and GD was not different in the seven patients who received during that time a L-thyroxine (L-T4) treatment than in those who were not treated. After methimazole onset all patients exhibited a prolonged remission of hyperthyroidism. In 8/12 patients this treatment is still being continued 2-7 years after its initiation. The mean methimazole dosage needed to maintain euthyroidism in these eight patients was 0.12 ± 0.02 mg/kg/day. In the remaining four patients methimazole was withdrawn from 1.9 to 7 years after its initiation and no relapses were recorded 2.0-2.1 years after its withdrawal. These patients developed, 0.1-0.3 years after methimazole withdrawal, a picture of overt hypothyroidism and needed treatment with L-T4, that is now being continued. No patients needed non-pharmacological therapies.

CONCLUSIONS

1) DS children might be incline to manifest over time a phenotypic metamorphosis from HT to GD and to subsequently fluctuate from hyperthyroidism to hypothyroidism; 2) in DS GD may have a mild biochemical and clinical course.