Epidemiology of Childhood Hyperthyroidism in France: A Nationwide Population-Based Study

Communicating exploratory unsupervised machine learning analysis in age clustering for paediatric disease

BACKGROUND

Despite the increasing availability of electronic healthcare record (EHR) data and wide availability of plug-and-play machine learning (ML) Application Programming Interfaces, the adoption of data-driven decision-making within routine hospital workflows thus far, has remained limited. Through the lens of deriving clusters of diagnoses by age, this study investigated the type of ML analysis that can be performed using EHR data and how results could be communicated to lay stakeholders.

METHODS

Observational EHR data from a tertiary paediatric hospital, containing 61 522 unique patients and 3315 unique ICD-10 diagnosis codes was used, after preprocessing. K-means clustering was applied to identify age distributions of patient diagnoses. The final model was selected using quantitative metrics and expert assessment of the clinical validity of the clusters. Additionally, uncertainty over preprocessing decisions was analysed.

FINDINGS

Four age clusters of diseases were identified, broadly aligning to ages between: 0 and 1; 1 and 5; 5 and 13; 13 and 18. Diagnoses, within the clusters, aligned to existing knowledge regarding the propensity of presentation at different ages, and sequential clusters presented known disease progressions. The results validated similar methodologies within the literature. The impact of uncertainty induced by preprocessing decisions was large at the individual diagnoses but not at a population level. Strategies for mitigating, or communicating, this uncertainty were successfully demonstrated.

CONCLUSION

Unsupervised ML applied to EHR data identifies clinically relevant age distributions of diagnoses which can augment existing decision making. However, biases within healthcare datasets dramatically impact results if not appropriately mitigated or communicated.

Overall, sex-and race/ethnicity-specific prevalence of thyroid dysfunction in US adolescents aged 12-18 years

Background

Thyroid dysfunction significantly affects the health and development of adolescents. However, comprehensive studies on its prevalence and characteristics in US adolescents are lacking.

Methods

We investigated the prevalence of thyroid dysfunction in US adolescents aged 12-18 years using data from the National Health and Nutrition Examination Survey (NHANES) 2001-2002 and 2007-2012 cycles. Thyroid dysfunction was assessed using serum thyroid-stimulating hormone (TSH) and free thyroxine (fT4) measurements. We analyzed the prevalence across demographic subgroups and identified associated risk factors.

Results

The study included 2,182 participants, representing an estimated 12.97 million adolescents. The group had a weighted mean age of 15.1 ± 0.06 years, with males constituting 51.4%. Subclinical hyperthyroidism emerged as the most prevalent thyroid dysfunction, affecting 4.4% of the population. From 2001-2002 to 2011-2012, subclinical hyperthyroidism remained consistent at 4.99% vs. 5.13% in the overall cohort. Subclinical and overt hypothyroidism was found in 0.41 and 1.03% of adolescents respectively, and overt hyperthyroidism was rare (0.04%). The prevalence of thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) positivity in the overall population were 5.8 and 9.8%, respectively. Positivity for TgAb was risk factors for hypothyroidism, while older age, female and Black Americans were risk factors for hyperthyroidism. Female adolescents and adolescents with an older age were more likely to be positive for TPOAb and TgAb, while Black and Mexican Americans had a lower risk of TPOAb and TgAb positivity.

Conclusion

Subclinical hyperthyroidism was the most common form of thyroid dysfunction, and its prevalence remained stable from 2001-2002 to 2011-2012. Notable disparities in the prevalence of hyperthyroidism and antibody positivity were observed among different age, sex and racial/ethnic groups.

Neutropenia Occurs More Often Under Carbimazole than Under Methimazole Treatment in Pediatric Graves' Disease Patients

Background: Agranulocytosis is a rare antithyroid drug treatment (ATD) side effect seen in children suffering from Graves' disease (GD). Neutropenia is a recognized adverse event associated with ATD but has also been reported as pre-treatment neutropenia in GD. Methods: We performed a retrospective cohort study to analyze the longitudinal clinical and biochemical data of 161 pediatric patients with GD who received either methimazole (MMI) or carbimazole (CBZ) as ATD. The inclusion criteria were elevated free thyroxine (fT4 >25 pmol/L), suppressed thyrotropin (TSH <0.05 mlU/mL), and elevated thyrotropin receptor antibodies (TSHRAbs >2.5 IU/L). Absolute neutrophil count (ANC) was used to define neutropenia (ANC <1800/µL) and agranulocytosis (ANC <500/µL). Results: Nine of the 161 patients had neutropenia at diagnosis (ANC: 1348/µL ± 250) without further deterioration under ATD. In this subgroup, we found higher levels of free triiodothyronine (fT3: 31.45 pmol/L ± 3.99) at diagnosis in comparison with those who developed neutropenia (26.29 pmol/L ± 12.96; p = 0.07) and those without neutropenia before and during therapy (23.12 pmol/L ± 13.7; p = 0.003). Thirty-eight patients (23.6%) became neutropenic (ANC: 1479/µL ± 262) while receiving ATD. Neutropenia occurred after a mean of 551.8 (range: 10-1376) days, mostly without further deterioration. Two of these 38 patients developed agranulocytosis and underwent emergency thyroidectomy. The patients with neutropenia were significantly younger (p = 0.031). Neutropenia occurred significantly more often in patients receiving CBZ (50%; n = 20/40) than in those receiving MMI (16.5%; n = 18/110; p = 0.001). The minimum ANC was significantly lower in the CBZ (1971/µL ± 1008) than in the MMI group (2546 ± 959); p = 0.004. Conclusions: Neutropenia occurred significantly more often under CBZ than MMI. As this is potentially due to higher immunogenicity, we suggest that children with GD should be treated with MMI. Frequent measurements of ANC may be needed to detect severe agranulocytosis, although low pre-treatment ANC may not necessarily be a contraindication to ATD treatment. Young age may be potentially associated with an increased risk of reduced ANC. Further investigation is necessary to fully understand risk factors for neutropenia in children with GD.

Perioperative Care of a Child With Hyperthyroidism

In pediatric-aged patients, hyperthyroidism generally results from the autoimmune disorder, Graves' disease (GD). Excessive levels of thyroid hormones (triiodothyronine and thyroxine) result in irritability, emotional lability, nervousness, tremors, palpitations, tachycardia, and arrhythmias. The risk of morbidity and mortality is increased when surgical intervention is required in patients with hyperthyroidism due to the potential for the development of thyroid storm (TS). A 3-year, 1-month-old child with a past medical history of GD presented for total thyroidectomy when pharmacologic control with methimazole was not feasible due to intolerance following development of a serum sickness-like illness. Prior to surgery, his thyrotoxicosis symptoms worsened with fever, tachycardia, diaphoresis, and hypertension. He subsequently developed TS and was admitted to the pediatric intensive care unit where management included hydrocortisone, potassium iodide, and β-adrenergic blockade with esmolol and propranolol. Thyroid studies improved prior to surgery, and a total thyroidectomy was successfully completed. Corticosteroid therapy was slowly tapered as an outpatient, and he was discharged home on hospital day 9. Following discharge, his signs and symptoms of thyrotoxicosis resolved, and he was started on oral levothyroxine replacement therapy. The remainder of his postoperative and post-discharge course were unremarkable. Only two case reports of perioperative pediatric TS have been published in the past 20 years. Our case serves as an important reminder of the signs of TS in children and to outline the treatment options in a pediatric patient, especially in those unable to tolerate first-line pharmacologic therapies such as methimazole or propylthiouracil.

Functional enrichment analysis of mutated genes in children with hyperthyroidism

Objective

Hyperthyroidism in Chinese children is relatively high and has been increasing in recent years, which has a significant impact on their healthy development. Hyperthyroidism is a polygenic disorder that presents greater challenges in terms of prediction and treatment than monogenic diseases. This study aims to elucidate the associated functions and gene sets of mutated genes in children with hyperthyroidism in terms of the gene ontology through GO enrichment analysis and in terms of biological signaling pathways through KEGG enrichment analysis, thereby enhancing our understanding of the expected effects of multiple mutated genes on hyperthyroidism in children.

Methods

Whole-exome sequencing was performed on the DNA samples of children with hyperthyroidism. Screening for pathogenic genes related to hyperthyroidism in affected children was performed using the publicly available disease databases Malacards, MutationView, and Clinvar, and the functions and influences of the identified pathogenic genes were analyzed using statistical analysis and the gene enrichment approach.

Results

Through GO enrichment analysis, it was found that the most significant gene ontology enrichment was the function "hormone activity" in terms of gene ontology molecular function. The corresponding mutated genes set that has common effects on hyperthyroidism in children included TG, CALCA, POMC, CGA, PTH, GHRL, FBN1, TRH, PRL, LEP, ADIPOQ, INS, GH1. The second most significant gene ontology enrichment was the function "response to peptide hormone" in terms of biological process. The corresponding mutated genes set that has common effects on hyperthyroidism in children included LRP6, TSC2, KANK1, COL1A1, CDKN1B, POMC, STAT1, MEN1, APC, GHRL, TSHR, GJB2, FBN1, GPT, LEP, ADIPOQ, INS, GH1. Through KEGG enrichment analysis, it was found that the most significant biological signaling pathway enrichment was the pathway "Thyroid hormone signaling pathway" function. The corresponding mutated genes set that has common effects on hyperthyroidism in children included NOTCH3, MYH7, TSC2, STAT1, MED13L, MAP2K2, SLCO1C1, SLC16A2, and THRB. The second most significant biological signaling pathway enrichment was the pathway "Hypertrophic cardiomyopathy" in terms of biological process. The corresponding mutated genes set that has common effects on hyperthyroidism in children included IGF1, CACNA1S, MYH7, IL6, TTN, CACNB2, LAMA2, and DMD.

Conclusion

The mutated genes in children with hyperthyroidism were closely linked to function involved in "hormone activity" and "response to peptide hormone" in terms of the biological signaling pathway, and to the functional pathways involved in "Thyroid hormone signaling pathway" and "Hypertrophic cardiomyopathy" in terms of the biological signaling pathway.

Optical coherence tomography angiography findings in pediatric patients with graves ophthalmopathy

PURPOSE

The aim of this study was to evaluate peripapillary, macular microvascular structure, and retinal nerve fiber layer (RNFL) thickness profile in children with Graves Ophthalmopathy (GO).

MATERIAL AND METHODS

Thirty-six eyes of 18 children with GO were prospectively compared with 40 eyes of 20-age and sex-matched controls. The severity and activity of the disease were evaluated according to the criteria of the European Group on Graves' Ophthalmopathy (EUGOGO) and Clinical Activity Score (CAS). After complete ophthalmologic and endocrinologic examination, all patients underwent optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) measurements. Retinal nerve fiber layer (RNFL) thickness, macular superficial capillary plexus (SCP), deep capillary plexus (DCP), foveal avascular zone (FAZ) area, acircularity index (AI) of the FAZ and peripapillary microvascular structure were analyzed.

RESULTS

The mean age was 12.1 ± 2.4 years in the GO group and 11.2 ± 2.6 years in healthy control group (p = 0.11). Duration of disease was 8.9 ± 4.2 months in the GO group. All patients in GO group had mild and inactive ophthalmopathy. In temporal inferior quadrant, RNFL thickness was significantly thinner in the GO group compared to the control group (p = 0.03). No significant difference was seen between groups both peripapillary and macular microvascular structure (all p > 0.05).

CONCLUSION

GO has no effect on optic nerve thickness, peripapillary and macular vascular parameters except inferior temporal RNFL in children.

What we know about the relationship between autoimmune thyroid diseases and gut microbiota: a perspective on the role of probiotics on pediatric endocrinology

INTRODUCTION

Autoimmune diseases account for a cumulative overall prevalence of about 3-5% worldwide. Among them, autoimmune thyroid diseases (ATDs) are the most common and comprise two main entities: Hashimoto's thyroiditis (HT) and Graves-Basedow disease (GD). The pathogenesis of ATDs remains not fully elucidated, however the role of microbioma has been proposed. Gut microbiota exert an important influence on the intestinal barrier, nutrient metabolism and immune system development and functions.

EVIDENCE ACQUISITION

In this review, we describe on the main features of ATDs in pediatrics, focusing on the reciprocal influence between gut microbiota, thyroid hormone metabolism and thyroid autoimmunity and consider the role of probiotics and other microbiota-targeted therapies in thyroid diseases with a perspective on pediatric endocrinology.

EVIDENCE SYNTHESIS

Microbiome affects both endogenous and exogenous thyroid hormone metabolism and influences the absorption of minerals important to the thyroid function, which are iodine, selenium, zinc and iron. The alteration of the gut microbiota, with the consequent modifications in the barrier function and the increased gut permeability, seems involved in the development of autoimmune and chronic inflammatory diseases, including ATDs. The supplementation with probiotics showed beneficial effects on the thyroid hormone and thyroid function because this strategy could restore the intestinal eubiosis and the good strain microorganism proliferation.

CONCLUSIONS

Even though the evidence about the interaction between microbiota and ATDs in pediatric patients is limited, the promising results obtained in the adult population, and in other autoimmune disorders affecting children, highlight the need of for further research in the pediatric field.

Approach to the Patient: Management and the Long-term Consequences of Graves' Disease in Children

In children, Graves' disease (GD) is the most common cause of hyperthyroidism. Most pediatric patients with GD will not go into lasting remission, even following many years of antidrug therapy. Thus, most pediatric patients will require radioactive iodine (RAI) or surgery. When antithyroid drugs are used, methimazole is the drug of choice. When methimazole is used in children, up to 20% will have minor adverse reactions and serious adverse events occur in up to 1%. RAI is an effective form of therapy when the thyroid size is less than 80 g. Because of concerns of whole-body radiation exposure, it is recommended that RAI be avoided in children under 5 years of age, and dosages less than 10 mCi be used between 5 and 10 years of age. Surgery is an effective treatment in children if performed by a high-volume thyroid surgeon. Because of the scarcity of high-volume pediatric thyroid surgeons, a multidisciplinary approach using pediatric surgeons and endocrine surgeons can be considered. Whereas there is a trend toward long-term antithyroid drug therapy in adults, for several reasons, this approach may not be practical for children. Determining the optimal treatment for the pediatric patient with GD, requires consideration of the risks and benefits relating to age and likelihood of remission.

Long-term management of Graves disease: a narrative review

Graves disease (GD) is the most common cause of hyperthyroidism, accounting for more than 90% of cases in Korea. Patients with GD are treated with any of the following: antithyroid drugs (ATDs), radioactive iodine (RAI) therapy, or thyroidectomy. Most patients begin treatment with ATDs, and clinical guidelines suggest that the appropriate treatment period is 12 to 18 months. While RAI treatment and surgery manage thyrotoxicosis by destroying or removing thyroid tissue, ATDs control thyrotoxicosis by inhibiting thyroid hormone synthesis and preserving the thyroid gland. Although ATDs efficiently control thyrotoxicosis symptoms, they do not correct the main etiology of GD; therefore, frequent relapses can follow. Recently, a large amount of data has been collected on long-term ATDs for GD, and low-dose methimazole (MMZ) is expected to be a good option for remission. For the long-term management of recurrent GD, it is important to induce remission by evaluating the patient's drug response, stopping ATDs at an appropriate time, and actively switching to surgery or RAI therapy, if indicated. Continuing drug treatment for an extended time is now encouraged in patients with a high possibility of remission with low-dose MMZ. It is also important to pay attention to the quality of life of the patients. This review aimed to summarize the appropriate treatment methods and timing of treatment transition in patients who relapsed several times while receiving treatment for GD.

Update on Pediatric Hyperthyroidism

Typical symptoms which should lead to suspicion of hyperthyroidism are unintentional weight loss, tachycardia, and palpitations, heat intolerance, and hyperactivity. It is diagnosed by suppressed thyroid-stimulating hormone (TSH) with elevated thyroid hormone (TH) levels. Graves' disease (GD) due to antibodies stimulating the TSH receptor is the leading cause, and first-line treatment is with methimazole (MMI). Emerging data suggest MMI treatment, up to 8 years is effective and safe in improving the rate of remission. Radioactive iodine (RAI) and thyroidectomy offer definitive treatment and induce permanent hypothyroidism. Thyroid storm is a life-threatening condition with systemic decompensation and hyperpyrexia. Neonates of mothers with current or past GD are at risk for neonatal hyperthyroidism (NH). Appropriate identification and follow-up of at-risk neonates will reduce complications.

Hyperthyroidism in children and adolescents: Experience in a university hospital in Colombia

Introduction: Hyperthyroidism is a heterogeneous condition characterized by the excessive production of thyroid hormones. It represents a diagnostic and therapeutic challenge. Objective: To describe the clinical and paraclinical characteristics and the evolution and differences between the main etiologies in patients with hyperthyroidism treated by the Pediatric Endocrinology Service at the Hospital Universitario San Vicente Fundación in Medellín, Colombia, between July 1st., 2015, and June 30th., 2020. Materials and methods: We conducted a cross-sectional observational study with retrospective data collection. Results: We included 54 patients with a mean age of 11.9 years, 72.2% of whom were female; 85.2% had no history of comorbidities related to autoimmunity; 11.1% had a family history of Graves’ disease, and 29.6% of other thyroid diseases. Goiter was the most frequent clinical manifestation (83.3%) and 92.6% of the patients received treatment with methimazole, 79.6% required beta-blockers, and 11.2% additional drug therapy. Adverse drug reactions occurred in 16.7% of the patients and in 20.4% there was a resolution of hyperthyroidism (spontaneous: 9.3%; after radio-iodine ablation: 9.3%, and after surgery: 1.9%). Conclusion: Hyperthyroidism is a disease with diverse clinical manifestations. Its most frequent cause is Graves’ disease followed by hashitoxicosis, which in this study had a higher frequency than that reported in the literature. The duration and side effects of pharmacological treatment were similar to those previously reported, but the higher frequency of agranulocytosis is noteworthy.

[Definitive treatment of Graves' disease in children]

BACKGROUND

Hyperthyreoidism due to Graves' disease is a rare disorder in pediatric practice. There is 2 treatment options in Graves' disease: medical treatment and definitive treatment, including surgery and radioactive iodine. Each method has its advantages and disadvantages. If medical therapy is ineffective the choice between radical treatment method is raised: radioactive iodine or total thyroidectomy. In this research we analyze treatment outcomes in pediatric Graves' disease patients after different radical treatment methods.

AIM

Comparative analysis of radical treatment outcomes in pediatric patients with Graves' disease.

MATERIALS AND METHODS

Retrospective and prospective one-center research of 122 patients with Graves' disease after radical treatment (between 2016 and 2021)RESULTS: The mean age was 13.5±3,5 year at the moment of examination. Patients were divided into 2 groups due to the radical treatments method: 1 group (n=60) were children after surgical treatment, 2 group (n=62) - after radioactive iodine. The mean dose of medical treatment in these groups did not reliably differ (p=0,06), duration of the medical treatment was reliably longer in patients after radioactive iodine (p=0,024). Graves' orbitopathy was diagnosed in 58 patients (47,5%) and met equally often in both groups, but active stage of Graves' orbitopathy was diagnosed only in patients from the 1st group. Thyroid size was reliable bigger in patients from the 1st group (p=0,004), and thyroid gland nodes were diagnosed only in patients from 1st group (p=0,0007).

CONCLUSION

RI can be considered an effective and safe treatment for GD. The effectiveness of RI depends on the volume of the thyroid gland; according to the results of the constructed ROC curve, the risk of repeated RI is higher with a volume of more than 55 cm3. Also radioactive iodine is undesirable if there is signs of ophatalmopathy due to its possible deterioration. According to the results of the study hypoparathyroidism after surgical treatment was diagnosed in 20%, recurrent laryngeal nerve injury was diagnosed after surgical treatment in 5% of patients. In patients with identified nodular goiter according to the results of ultrasound, surgical treatment is preferable due to the impossibility of excluding thyroid cancer.

Pediatric Graves' orbitopathy: a multicentre study

PURPOSE

Graves' orbitopathy (GO) is a rare condition in children often considered to be a less severe condition than at an older age. The aim of our study was to analyse if there are any factors that distinguish paediatric from adult GO in order to provide guidelines for assessing and managing paediatric GO.

METHODS

Study design is a multicentre retrospective observational case series; 115 paediatric patients diagnosed with GO who visited our university medical centres in the Netherlands and Iran between 2003 and 2019 were submitted for complete ophthalmological examinations, serological testing and/or orbital imaging. Main outcome measures focussed on the natural course and clinical picture as well as medical and surgical treatment in paediatric GO.

RESULTS

Clinical findings included proptosis (n = 97; 84.3%), eyelid retraction (n = 77; 67%) and diplopia (n = 13; 11.3%). Ninety-two patients (80%) presented with mild disease, 21 (18.3%) with moderate-severe disease and two (1.7%) with severe GO. Five patients (4.3%) underwent intravenous glucocorticoids and 25 patients underwent orbital decompression surgery. Strabismus surgery due to primary involvement of extraocular muscles was performed in two patients (1.7%). Overall, rehabilitative surgical treatment was planned in 31 patients (26.9%) with inactive disease. Two patients experienced reactivation of the disease.

CONCLUSION

Despite the fact that paediatric and adult GO are considered two separate entities, they might be the same disease with two different clinical phenotypes. Paediatric GO population presents with a comparable clinical picture regarding both soft tissue involvement and proptosis, which may require surgical intervention. Proptosis was present in the majority of paediatric GO patients. Orbital decompression was performed in 21.7% of patients.

Hyperthyroidism in adolescents

The term 'hyperthyroidism' refers to a form of thyrotoxicosis due to inappropriate high synthesis and secretion of thyroid hormone(s) by the thyroid. The leading cause of hyperthyroidism in adolescents is Graves' disease (GD); however, one should also consider other potential causes, such as toxic nodular goitre (single or multinodular), and other rare disorders leading to excessive production and release of thyroid hormones. The term 'thyrotoxicosis' refers to a clinical state resulting from inappropriate high thyroid hormone action in tissues, generally due to inappropriate high tissue thyroid hormone levels. Thyrotoxicosis is a condition with multiple aetiologies, manifestations, and potential modes of therapy. By definition, the extrathyroidal sources of excessive amounts of thyroid hormones, such as iatrogenic thyrotoxicosis, factitious ingestion of thyroid hormone, or struma ovarii, do not include hyperthyroidism. The aetiology of hyperthyroidism/and thyrotoxicosis should be determined. Although the diagnosis is apparent based on the clinical presentation and initial biochemical evaluation, additional diagnostic testing is indicated. This testing should include: (1) measurement of thyroid-stimulating hormone receptor (TSHR) antibodies (TRAb); (2) analysis of thyroidal echogenicity and blood flow on ultrasonography; or (3) determination of radioactive iodine uptake (RAIU). A 123I or 99mTc pertechnetate scan is recommended when the clinical presentation suggests toxic nodular goitre. A question arises regarding whether diagnostic workup and treatment (antithyroid drugs, radioiodine, surgery, and others) should be the same in children and adolescents as in adults, as well as whether there are the same goals of treatment in adolescents as in adults, in female patients vs in male patients, and in reproductive or in postreproductive age. In this aspect, different treatment modalities might be preferred to achieve euthyroidism and to avoid potential risks from the treatment. The vast majority of patients with thyroid disorders require life-long treatment; therefore, the collaboration of different specialists is warranted to achieve these goals and improve patients' quality of life.

An Estimation of the Incidence of Thyroiditis Among Girls in Primary Care in Spain

OBJECTIVE

As for other auto-immune processes, thyroiditis is monitored after vaccinations. The aim was to estimate the baseline incidence of thyroiditis among girls, before investigating papillomavirus vaccination as a potential risk factor.

METHODS

Observational cohort study including girls aged 9-18 years and registered between 2002-2016 in the Spanish Primary Care Database for Pharmacoepidemiological Research. Girls were followed until a thyroiditis occurred, 19 years of age, left the cohort, died, or the study ended. Anonymized records were reviewed for diagnosis confirmation (endocrine discharge letter and/or free-text comments) in a random sample. Incidence rate (IR) per 10⁵ person years (/10⁵ py) was estimated.

RESULTS

The cohort numbered 480,169 girls, of whom 641 had a record of thyroiditis: 346 autoimmune thyroiditis; 17 thyroiditis of other types; and 278 unspecified. Incidence of recorded thyroiditis increased with age, from 23.96 at age 9 years to 47.91 at age 14 years, and stabilized around 31.06-34.43 among girls aged 15-18 years. Of the 98 records reviewed, 60.2% were ‘confirmed’ cases, 32.7% ‘possible’ and 7.1% were discarded. After correction for discarded cases, IR=20.83 ‘confirmed’ cases, increasing to 32.12/10⁵ py when ‘confirmed’ plus ‘possible’ cases were included. Between 2002-2005, incidences were lower (16.28 and 20.93 cases/10⁵ py) than in the period 2007-2016 (21.17 and 33.78 cases/10⁵ py) for ‘confirmed’ and ‘confirmed’ plus ‘possible’, respectively.

CONCLUSION

Two-thirds of the recorded thyroiditis included confirmatory evidence. The incidence of thyroiditis among girls increased with age and in the later period, and remained stable among girls aged 15-18 years.

Update on pediatric hyperthyroidism

PURPOSE OF REVIEW

This review is intended to highlight recent studies which provide new data on the epidemiology and management of children with hyperthyroidism, including neonates.

RECENT FINDINGS

A French study demonstrates differences in age-related trends in incidence of hyperthyroidism in males versus females and suggests the overall incidence may be increasing. New studies confirm the effectiveness and safety of long-term medical therapy (up to 10 years), including from the first randomized trial of short-term versus long-term therapy. Radioiodine ablation (RAI) is the main alternative therapy, though surgery may have some advantages if done in a high-volume center; using higher weight-based doses of I-131 (250 μCI/g thyroid tissue) could increase proportion of patients achieving hypothyroidism and decrease repeat ablations. Maternal or neonatal thyroid-stimulating hormone (TSH) receptor antibodies in children of mothers with Graves' disease, and TSH at 3-7 days of age are good predictors of which neonates will have problems.

SUMMARY

More research is needed on the epidemiology of Graves' disease. Long-term medical therapy well past two years should be considered an option in compliant patients to decrease the number who need definitive therapy. For those receiving RAI, a dose of about 250 μCI/g thyroid tissue should result in fewer cases of persistent hyperthyroidism than lower doses.

The Incidence of Childhood Thyrotoxicosis Is Increasing in Both Girls and Boys in Sweden

BACKGROUND

We found an increase in the incidence rate (IR) of childhood thyrotoxicosis (CT) during the 1990s in central Sweden. The optimal treatment method for CT is a subject that is still debated upon.

OBJECTIVES

To investigate whether the increase in IR of CT in Sweden persists and to study the treatment outcome.

METHOD

Children <16 years of age diagnosed with CT during 2000-2009 and living in 1 of 5 counties in central Sweden were identified retrospectively using hospital registers. Data on clinical and biochemical characteristics and outcomes of treatment were collected from medical records. The corresponding data from 1990 to 1999 were pooled with the new data.

RESULTS

In total, 113 children were diagnosed with CT during 1990-2009 in the study area. The overall IR was 2.2/100,000 person-years (95% CI 1.2-2.5/100,000 person-years). The IR was significantly higher during 2000-2009 than during 1990-1999 (2.8/100,000 [2.2-3.6] vs. 1.6/100,000 person-years [1.2-2.2], p = 0.006). The increase was significant for both sexes. Seventy percent of the patients who completed the planned initial treatment with antithyroid drugs (ATDs) and were not lost to follow-up relapsed within 3 years. Boys tended to relapse earlier than girls (6.0 months after drug withdrawal [95% CI 1.9-10.0] vs. 12.0 months [95% CI 6.8-17.3], p = 0.074).

CONCLUSIONS

The IR of CT is increasing in both girls and boys. Relapse rate after withdrawal of ATD treatment is 70%. Boys tend to relapse earlier than girls, and this needs to be further investigated.