Evaluation and management of the child with hypothyroidism

The role of DUOXA2 in the clinical diagnosis of paediatric congenital hypothyroidism

Background: Congenital hypothyroidism (CH) is a common metabolic disorder in children that can impact growth and neurodevelopment, particularly during infancy and early childhood. DUOXA2, a DUOX maturation factor, plays a crucial role in the maturation and activation of dual oxidase DUOX2 (a member of the NADPH oxidase family). DUOX2 can correctly migrate to the plasma membrane from the endoplasmic reticulum (ER) with the help of DUOXA2, and the two proteins together form a stable complex that promotes hydrogen peroxide (H2O2) generation in the synthesis of thyroid hormones. Genetic alterations in DUOXA2 lead to defects function of DUOX2 protein causing inherited CH.

Objectives: This review discusses the relationship between DUOXA2 and CH, including the pathogenic mechanisms of CH in children caused by DUOXA2 mutations and the possibility or promise of DUOXA2 gene screening as a diagnostic marker for CH in the clinic.

Methods: The review synthesizes current research on the biological role of DUOXA2 and DUOX2 in thyroid hormone synthesis, the molecular impact of DUOXA2 mutations, and the clinical implications of genetic screening for CH.

Results: Mutations in DUOXA2 disrupt this process of H2O2 generation in the synthesis of thyroid hormones , leading to inherited CH. Early identification through DUOXA2 gene screening could improve diagnostic accuracy, which facilitates early intervention and personalized treatment.

Conclusions: DUOXA2 gene screening holds promise for enhancing diagnostic accuracy in CH. However, it cannot be used as a sole diagnostic indicator, and to optimize diagnostic sensitivity, it should be combined with the screening of other relevant genetic mutations and diagnostic tools. Further research is needed to refine screening protocols and explore therapeutic options.

Congenital hypothyroidism and associated visual-motor and intellectual development

BACKGROUND

Congenital hypothyroidism's sequelae include visuomotor and intellectual developmental deficits. Visual-motor perception is a cognitive function related to academic performance. Intellect is the ability to learn and use acquired knowledge to solve and achieve goals. Our objective was to evaluate visual-motor and intellectual development in children with late initiation of treatment for congenital hypothyroidism enrolled in a developmental follow-up and intervention program.

METHODS

We evaluated the visual-motor and intellectual development of 75 infants with congenital hypothyroidism, 34 with athyrosis, and 41 with ectopia using the Bender Visual-Motor Development Test and the Weschler Intelligence Scale at eight and nine years of age.

RESULTS

Children with ectopia had a visual-motor delay of -2 years and an Intelligence Quotient (IQ) greater than 98 points. Children with athyrosis had a visual-motor delay equivalent to -3.2 years and an IQ below 90 points. Better performance on Bender's test was positively correlated with IQ. Attending more than 80% of Developmental Intervention Program appointments had a positive impact on intellectual development.

CONCLUSIONS

Timely diagnosis and early treatment with the appropriate dose of levothyroxine are determining factors; however, attendance to a development follow-up and intervention program could further support the cognitive development of children with congenital hypothyroidism.

IMPACT

Visuomotor development influences cognitive functions related to school performance. Deficits in the ability to learn and use acquired knowledge to solve problems and achieve goals are characteristic of children with congenital hypothyroidism. Delayed treatment is associated with more severe sequelae in both visual-motor and intellectual development. Here, we show that treatment with adequate doses of levothyroxine and inclusion in a follow-up and developmental program are highly recommended for patients with delayed treatment. A better understanding of these factors will allow clinicians to target therapeutic interventions.

Refractory hypothyroidism in children: an overview

Refractory hypothyroidism (RF) defined as raised serum levels of thyroid stimulating hormone (TSH) above upper limit of the reference range with or without the persistence of hypothyroid symptoms following a 6-week interval after the dosage was last increased to upper limits of dose per age. The most common cause of RH is inadequate compliance. In addition, diet, concomitant medication interactions, and gastrointestinal diseases can all result in l-thyroxine (LT4) malabsorption, which can cause RH. Moreover, weight gain, switching brands of LT4, poor storage of LT4, chronic liver disorders, cystic fibrosis, nephrotic syndrome, consumptive hypothyroidism, Addison's disease are significant contributors to RF in children. RH in children is frequently asymptomatic, when symptoms do occur, they are typically minor and resemble those of hypothyroidism. It is essential to identify RH early and treat its underlying cause in order to avoid overusing LT4, which can lead to cardiac and bone problems. Endocrinologists should handle children who they suspect of having RH methodically after making sure there is enough compliance. Searching for undiagnosed illnesses and/or other factors that can affect LT4 absorption could be part of this. We present this review after an extensive literature search and long-standing clinical experience. This review's objective is to shed light on the causes, clinical manifestations, investigations, and treatment of RH in children.

Minipuberty in Daughters of Women with Hypothyroidism during Pregnancy

Minipuberty is a term describing transient postnatal activation of the hypothalamic-pituitary-gonadal axis, likely playing an important role in the postnatal growth of female genital organs and breasts. Unlike infant boys, there are no data concerning the impact of gestational hypothyroidism on the course of minipuberty in infant girls. Therefore, the aim of the current study was to investigate the reproductive axis and genital organs in daughters of women with thyroid hypofunction during pregnancy. The study population included three matched groups of infant girls: offspring of women with thyroid hypofunction non-substituted or inadequately treated during gestation (group 1), descendants of women adequately substituted throughout pregnancy (group 2), and daughters of healthy women (group 3). Salivary concentrations of estradiol, progesterone, 17-hydroxyprogesterone, and androgens (testosterone, androstenedione, and dehydroepiandrosterone sulfate) and urine levels of gonadotropins were measured monthly from month 1 to month 6, once every two months between postnatal months 6 and 12, and once every three months between postnatal months 12 and 18. During each visit, we also determined ovarian volume, uterine length, and breast diameter. Concentrations of FSH, LH, and estradiol were lowest in group 1, and this group was also characterized by the shortest detection period for gonadotropins and estradiol. These differences were paralleled by differences in ovarian volume, uterine length, and breast diameter. There were no differences between groups 2 and 3 in levels of both hormones and in the size of the measured structures. The obtained results seem to indicate that non-substituted or inadequately substituted hypothyroidism during pregnancy may impair the course of minipuberty in the female offspring.

Exposure to MEHP during Pregnancy and Lactation Impairs Offspring Growth and Development by Disrupting Thyroid Hormone Homeostasis

Mono(2-ethylhexyl) phthalate (MEHP), as a highly toxic and biologically active phthalate metabolite, poses considerable risks to the environment and humans. Despite the existence of in vitro studies, there is a lack of in vivo experiments assessing its toxicity, particularly thyroid toxicity. Herein, we investigated the thyroid-disrupting effects of MEHP and the effects on growth and development of maternal exposure to MEHP during pregnancy and lactation on the offspring modeled by SD rats. We found that thyroid hormone (TH) homeostasis was disrupted in the offspring, showing a decrease in total TH levels, combined with an increase in free TH levels. Nonhomeostasis ultimately leads to weight loss in female offspring, longer anogenital distance in male offspring, prolonged eye-opening times, and fewer offspring. Our findings indicate that maternal exposure to MEHP during pregnancy and lactation indirectly influences the synthesis, transport, transformation, and metabolism of THs in the offspring. Meanwhile, MEHP disrupted the morphology and ultrastructure of the thyroid gland, leading to TH disruption. This hormonal disruption might ultimately affect the growth and development of the offspring. This study provides a novel perspective on the thyroid toxicity mechanisms of phthalate metabolites, emphasizing the health risks to newborns indirectly exposed to phthalates and their metabolites.

Allan-Herndon-Dudley syndrome in Hong Kong: Implication for newborn screening

BACKGROUND

Allan-Herndon-Dudley syndrome (MCT 8 deficiency) is an X-linked recessive condition caused by hemizygous pathogenic variants in SLC16A2 encoding the monocarboxylate transporter 8 (MCT8). Patients present with global developmental delay and neurological impairment, and abnormal serum thyroid function tests. The drug, 3,3',5 triiodothyroacetic acid (TRIAC), was recently demonstrated to improve the endocrinological profile. Improvement in diagnostic approach is key to earlier start of treatment.

PATIENT FINDINGS

We described four Chinese patients with MCT8 deficiency undergoing different diagnostic odysseys. Their initial presentation included global developmental delay and dystonia. Patient 2 also had epilepsy. Patients 1 and 2 presented with two novel variants: (1)hemizygous NM_006517.4(SLC16A2):c.1170 + 2 T > A; p.(?), and (2)hemizygous NM_006517.4(SLC16A2):c.305dupT; p.(Val103GlyfsTer17) respectively. Patients 3 and 4 were biological brothers harboring hemizygous NM_006517.4(SLC16A2):c.305dupT; p.(Val103GlyfsTer17), which was first reported in 2004. We obtained the measurement of triiodothyronine (T3) and reverse T3 (rT3) from dried blood spot samples collected on Day 1 of life from Patient 1 and studied the biomarkers (rT3 and T3/rT3 ratio) proposed by Iwayama et al. for the detection of MCT8 deficiency at birth. Our data verified the significantly reduced rT3 level in Patient 1, compared with healthy newborns, although low T3 level and comparable T3/rT3 ratio with controls were detected.

SUMMARY

Patients with MCT8 deficiency often undergo diagnostic odysseys. An early diagnosis could be missed by a normal newborn thyroid function screening result based on biochemical measurement of TSH and/or T4/fT4. Early detection of rT3 is key to improving current diagnostic approach.

CONCLUSION

We recommend that full thyroid function profile (TSH, T4/fT4, T3/fT3, rT3) be considered early for all pediatric patients presenting with unexplained developmental delay and/or dystonia. The potential inclusion of rT3 measurement in newborn screening may prove promising.

The interplay of common genetic variants NRG1 rs2439302 and RET rs2435357 increases the risk of developing Hirschsprung's disease

Introduction: As a congenital and genetically related disease, many single nucleotide polymorphisms (SNPs) have been reported to be associated with the risk of HSCR. Our previous research showed that SNP rs2439302 (NRG1) interacted with rs2435357 (RET) to increase the risk of HSCR development. However, the underlying molecular mechanism is still not well understood. Methods: SNP rs2439302 (NRG1) and rs2435357 (RET) were genotyped in 470 HSCR cases. The expression of NRG1 and RET was investigated in the colon of HSCR patients. Knockdown of the NRG1 and RET homologs was performed in zebrafish to investigate their synergistic effect on ENS development. The effect of SNP rs2439302 and rs2435357 polymorphism on neuron proliferation, migration, and differentiation were investigated in SHSY-5Y cells and IPSCs. Results: Significant downregulation of NRG1 and RET expression was noticed in the aganglionic segment of HSCR patients and SHSY-5Y cells with rs2439302 GG/rs2435357 TT genotype. NRG1 and RET double mutants caused the most severe reduction in enteric neuron numbers than NRG1 single mutant or RET single mutant in the hindgut of zebrafish. SHSY-5Y cells and IPSCs with rs2439302 GG/rs2435357 TT genotype exhibited a decreased proliferative, migration, and differentiative capacity. CTCF showed a considerably higher binding ability to SNP rs2439302 CC than GG. NRG1 reduction caused a further decrease in SOX10 expression via the PI3K/Akt pathway, which regulates RET expression by directly binding to rs2435357. Discussion: SNP rs2439302 (NRG1) GG increases the risk of developing HSCR by affecting the binding of transcription factor CTCF and interacting with rs2435357 (RET) to regulate RET expression via the PI3K/Akt/SOX10 pathway.

JAK3/STAT5b/PPARγ Pathway Mediates the Association between Di(2-ethylhexyl) Phthalate Exposure and Lipid Metabolic Disorder in Chinese Adolescent Students

Our previous studies found that di (2-ethylhexyl) phthalate (DEHP) could disorder lipid metabolism in adolescents but the mechanisms underlying this association remained unclear. This study was undertaken to clarify the mediating effect of JAK3/STAT5/PPARγ on disorder lipid levels induced by DEHP in adolescents. We recruited 478 adolescent students (median age 18.1 years). The mRNA expression and DNA methylation levels of JAK3/STAT5/PPARγ were detected by real-time PCR and the MethylTarget, respectively. We used multiple linear regression to analyze the association between DEHP metabolites (MEHP, MEOHP, MEHHP, MECPP, MCMHP, and ΣDEHP) levels, mRNA expression, and DNA methylation levels. The mediating effect of JAK3/STAT5/PPARγ mRNA expression levels was examined by mediation analysis. We found that all DEHP metabolite levels were positively correlated with TC/HDL-C and LDL-C/HDL-C (P < 0.05). The MEOHP level was negatively associated with DNA methylation levels and positively associated with mRNA levels of PPARγ and STAT5b (P < 0.05). The MEHP level was negatively associated with the DNA methylation level and positively associated with the mRNA level of JAK3 (P < 0.05). Higher MEOHP was associated with a higher level of TC/HDL-C, the mediation analysis showed the mediation effect was 17.18% for the JAK3 level, 10.76% for the STAT5b level, and 11% for the PPARγ level. Higher MEHP was associated with a higher level of LDL-C/HDL-C, the mediation effect was 14.49% for the JAK3 level. In conclusion, DEHP metabolites decreased the DNA methylation levels, inducing the increase of the mRNA levels of JAK3/STAT5/PPARγ. In addition, the mRNA levels mediated the association between DEHP exposure and disorder lipid levels.

Identifying elevated plasma free triiodothyronine levels: age-adapted reference intervals for pediatrics

OBJECTIVES

Elevated free T3 (FT3) is an important feature for the early diagnosis of several diseases among which Grave's disease or Allan-Hernon-Dudley syndrome. However, there is a lack of age-adapted reference intervals for plasma thyroid hormones in children. We conducted a study to define reference values of peripheral FT3 in children using a commonly used automated immunoassay.

METHODS

All thyroid function test (TFT) results from our lab collected during 9 months were extracted anonymously, and reference intervals establishment followed recommendations validated by International Federation of Clinical Chemistry (IFCC).

RESULTS

We defined five reference intervals covering the whole pediatric period. Overall, 26.1% of peripheral FT3 measured in children with normal TSH are out of the adult reference range, and 22.2% are upper it leading to misinterpretation. In a 9-month old patient with severe neurodevelopmental disorders, a pathological elevated FT3 has been securely interpreted using the newly established interval.

CONCLUSIONS

The study highlights the poor relevance of adult intervals in pediatric cares, as it confirms that plasmatic FT3 is higher during the whole pediatric period. This work reports useful age-adapted reference intervals for free T3 in pediatrics using a widely used electrochemiluminescent Immunoassay (ECLIA) kit.

Free thyroxine measurement in clinical practice: how to optimize indications, analytical procedures, and interpretation criteria while waiting for global standardization

Thyroid dysfunctions are among the most common endocrine disorders and accurate biochemical testing is needed to confirm or rule out a diagnosis. Notably, true hyperthyroidism and hypothyroidism in the setting of a normal thyroid-stimulating hormone level are highly unlikely, making the assessment of free thyroxine (FT4) inappropriate in most new cases. However, FT4 measurement is integral in both the diagnosis and management of relevant central dysfunctions (central hypothyroidism and central hyperthyroidism) as well as for monitoring therapy in hyperthyroid patients treated with anti-thyroid drugs or radioiodine. In such settings, accurate FT4 quantification is required. Global standardization will improve the comparability of the results across laboratories and allow the development of common clinical decision limits in evidence-based guidelines. The International Federation of Clinical Chemistry and Laboratory Medicine Committee for Standardization of Thyroid Function Tests has undertaken FT4 immunoassay method comparison and recalibration studies and developed a reference measurement procedure that is currently being validated. However, technical and implementation challenges, including the establishment of different clinical decision limits for distinct patient groups, still remain. Accordingly, different assays and reference values cannot be interchanged. Two-way communication between the laboratory and clinical specialists is pivotal to properly select a reliable FT4 assay, establish reference intervals, investigate discordant results, and monitor the analytical and clinical performance of the method over time.

Thyroid Disorders Spectrum in Pediatric Endocrine Clinic; Seven-Year Experience of a Teaching Hospital in Saudi Arabia

Thyroid disorders constitute one of the major endocrine disorders in pediatric service. It includes a range of congenital versus acquired anatomic and/or functional thyroid diseases in growing children that has a spectrum of severity from severe intellectual disability effect to subclinical mild pathologies. This study was designed to analyze the demographic characteristics, clinical pattern, and severity of thyroid disorders in the pediatric endocrine clinic patients at the teaching hospital of the university over a 7-year duration. A total number of 148 patients with thyroid disorders were seen in pediatric Endocrine clinic during the time between January 2015 and December 2021. Female patients constitute 64% of them. Acquired Hypothyroidism was the commonest disorder; 34% of the cases followed by the congenital hypothyroidism (CH), then Hashimoto's thyroiditis, and 5.8% for others. While a very small percentage was acquired hyperthyroidism. The majority of referrals were from dermatology and other service for the screening of thyroid disease as association with other autoimmune diseases with percentage of 28.3%. Next was neck swelling manifestation in 22.6%. Thyroid disorders in children, both congenital and acquired, constitute an important medical issue for pediatricians to be aware of its variable presentations, and its potential serious health consequences on the affected children if not diagnosed and treated earlier. Acquired hypothyroidism constitutes more percentage of the thyroid disorders followed in the pediatric endocrinology outpatient clinics. Congenital hypothyroidism is the second most common thyroid disorder in the outpatient unit, having the most potential complications. These results support the international studies with the female predominance in most of thyroid disorders.

The management and metabolic characterization: hyperthyroidism and hypothyroidism

Hyperthyroidism and hypothyroidism are common diseases resulting from thyroid dysfunction, and are simple to diagnose and treat. The traditional treatment for hypothyroidism is thyroid hormone replacement therapy. The traditional treatments for hyperthyroidism include antithyroid drug, iodine radiotherapy, and surgery. Thyroid disease can be fatal in severe cases if untreated. Current statistical reference ranges used for diagnosis based on relevant biochemical parameters have been debated, and insufficient treatment can result in long-term thyroid hormone deficiency, which is associated with increased risk of cardiovascular disease and persistent symptoms. In contrast, overtreatment can result in heart disease and osteoporosis, particularly in older people and pregnant women. Therefore, under- or over-treatment should be avoided and treatment regimens should be monitored closely. A significant proportion of patients who achieve biochemical treatment goals still complain of significant symptoms. Systematic literature review was performed through the Embase (Elsevier), PubMed and Web of Science databases, and studies summarized evidence regarding treatment and management of hypothyroidism and hyperthyroidism, and reviewed clinical practice guidelines. We also reviewed the latest research on the metabolic mechanisms of hyperthyroidism and hypothyroidism, which contributed to understanding of thyroid diseases in the clinic. A reliable algorithm is needed to management, assessment, and treatment patients with hyperthyroidism and hypothyroidism, which can not only improve management efficiency, but also providing a broad application. In addition, the thyroid disorder showed a lipid metabolism tissue specificity in the Ventromedial Hypothalamus, and effect oxidative stress and energy metabolism of whole body. This review summarizes an algorithm for thyroid disease and the latest pathogenesis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition.

Iodine Status in Pregnant Women Having Urinary Fluoride in Contaminated Areas: A Case Study of Phayao Province

Fluoride naturally occurs in the Earth's crust and is widely dispersed in groundwater. The high consumption of fluoride can inhibit iodine metabolism in the human body, especially in the thyroid gland. This study assessed iodine knowledge, iodine consumption behavior, urinary iodine (UI), thyroid stimulating hormone (serum TSH), and free triiodothyronine3 (serum FT3) and examined the connection between fluoride exposure and UI and thyroid function as serum concentrations of TSH and FT3 in pregnant women dwelling in an area of endemic fluorosis. This was a cross-sectional study. The population included 152 pregnant women within the 1^st trimester of pregnancy, during which they were provided antenatal care (ANC) in seven public community hospitals in Phayao province, Thailand. The study consisted of two components. First, the study consisted of a questionnaire in which we evaluated the iodine knowledge and iodine consumptive behaviors in subjects. Second, biochemical data were investigated to evaluate thyroid function in the subjects. The gestational age of most subjects was 8-12 weeks. The study population has lived in fluoride-contaminated areas since birth (76.97%). The iodine and iodine consumption levels were moderate (50.00%). Their food iodine consumption was 3-4 days/week, and the top five consumption ranks were iodized salt, cooked pork, eggs, sticky rice, and iodine fish sauce. In terms of biochemical parameters, 63.16% of respondents had UI levels below 150.00 g/L, which is below the normal reference range of 150.00-249.00 g/L. 89.47% of the risk of hypothyroidism was associated with serum TSH levels below 2.50 g/L. In 38.16% of the samples, normal levels of serum FT3 (2.00-4.40 pg/L) were identified in the subjects. In addition, 61.84% of the samples had FT3 concentrations greater than 4.40 pg/L (high intake of iodine). The approved association between positive serum FT3 data and serum TSH was positive (r = 260 and p < 0.05). These studies imply that these elevated levels of TSH and FT3 place pregnant women in their first trimester at risk for hypothyroidism.

Thyroid function screening and follow-up of children with abdominal distension in Nanjing, China: a cross-sectional study

OBJECTIVE

To describe the thyroid function test among children with abdominal distention and to follow up the treatment received by children with abnormal thyroid function.

DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

A total of 1089 children (median age:30 days (IQR=21-60 days) with abdominal distension were included in this single centre study in Nanjing, China.

RESULT

Thyroid dysfunction was found in 43 of 148 Hirschsprung's disease (HSCR) cases, with 3 (2.03%) having hypothyroidism, 3 (2.03%) having subclinical hypothyroidism and 3 (2.03%) having subclinical hyperthyroidism. Thyroid dysfunction was found in 206 of 941 functional abdominal distension cases, with 4 (0.43%) having hypothyroidism, 23 (2.4%) having subclinical hypothyroidism, 28 (2.9%) having subclinical hyperthyroidism and 1 (0.11%) having hyperthyroidism. Among total 65 cases (9 from HSCR, 56 from functional abdominal distension) diagnosed with thyroid diseases, 12 were treated with levothyroxine (LT-4), of which 9 were discontinued treatment at about 2 years old, and 3 were still receiving LT-4. Thirty-two cases received no treatment and thyroid function returned to normal in about 1 month. Twenty-one cases were lost during the follow-up.

CONCLUSION

The paediatrician should be vigilant for hypothyroidism when dealing with children with abdominal distension. Thyroid function should be followed up rather than simply administering a short-term levothyroxine treatment.

Resolved Severe Primary Hypothyroidism in Sensenbrenner Syndrome Post Hepatorenal Transplantation: A Case Report

INTRODUCTION

Sensenbrenner syndrome, or cranioectodermal dysplasia (OMIM #218330), is a rare genetic condition inherited as an autosomal recessive with less than 70 reported cases worldwide. It results in multiorgan abnormalities along with ectodermal structural defects. No previous reported cases demonstrated primary hypothyroidism in a matter of Sensenbrenner syndrome.

CASE PRESENTATION

Herein, we report a 6-year-old girl who suffered from progressive liver failure and end-stage renal disease secondary to Sensenbrenner syndrome, which was associated with severe primary hypothyroidism that completely recovered after a combined renal and liver transplant.

CONCLUSION

For the first time in the literature, we report an association of Sensenbrenner syndrome with hypothyroidism that resolved after a combined renal and liver transplant. Such findings expand the clinical spectrum of this syndrome. However, a larger cohort is needed to confirm or exclude such an association. Our case highlights the importance of thyroid function monitoring in any patient with renal and liver failure prior to and after a hepatorenal transplant.

Preparation of Levothyroxine Transdermal Gels and Preliminary Pharmacokinetic Study in Hypothyroidism Rat Model

Background:

Hypothyroidism is a common disorder due to inadequate thyroid hormone secretion. In patients with hypothyroidism, levothyroxine (LT4) is the treatment of choice, and tablets are the most common dosage form. However, the main limitation of tablet LT4 is malabsorption.

Objective:

This study intends to develop a new dosage form of percutaneous drug delivery for levothyroxine. Absorption of levothyroxine sodium through the application of gel formulation was studied using a hypothyroidism rat model.

Methods:

A formulation of levothyroxine sodium gel was developed and selected. In-vitro transdermal experiments were performed using the vertical Franz diffusion pool method, and gel formulation was used for animal research (hypothyroidism rats model). Total 30 rats were randomly divided into 6 groups, and one was the normal control group. The other 5 groups were prepared as hypothyroidism models. After applying different doses of gel preparation to the rat model, we measured serum total thyroxine (TT4), free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) using fluorescence determination of luminescence immunoassay.

Results:

The optimum formulation of levothyroxine gels comprised 20% polyvinyl alcohol (PVA), 5% glycerol, 2% azone, and 6% oleic acid. The application of levothyroxine sodium gel resulted in quick and smooth action so that the predicted level of the normal control group could be reached within 2 weeks, and it lasted steadily for 8 weeks.

Conclusion:

This research study successfully developed and tested an optimal formulation of levothyroxine gel with therapeutic benefit on hypothyroidism in rats.

Pathological damage of thyroidopathy and the prevalence of thyroid diseases in children of the Perm region

Relevance. Thyroid diseases in children and adolescents rank first in the structure of endocrine pathology. An issue related to comparability of data on prevalence obtained with different procedures is vital given the necessity to intensify activities aimed at optimizing prevention of thyroid pathology.

The aim. Comparative analysis of pathological lesions of thyropathies and the prevalence of thyroid gland diseases in children and adolescents living in the territory of the Perm region.

Materials and methods. Prevalence of thyroid diseases was analyzed based on data taken from Statistic Form No. 12. Pathological damage caused by thyroid diseases was calculated based on results produced by medical examinations that included laboratory tests, ultrasound scanning of the thyroid gland, and a check-up by an endocrinologist. Calculation results were then compared with data taken from statistic reports. Influence exerted by sex and age on the growth in thyrotrophic hormone contents and thyroid gland volume was assessed by analyzing values in one-factor logistic regression models.

Results. Prevalence of thyroid diseases, endemic goiter and subclinical hypothyroidism tends to decrease among children living in Perm region (р = 0.003–0.015) but prevalence of thyroiditis remains stable (р = 0.794). Having assessed prevalence among teenagers, we did not reveal any dynamics in prevalence of thyroid diseases and thyroiditis (р = 0.129–0.248); prevalence of endemic goiter went down in this age group (р = 0.008) whereas prevalence of subclinical hypothyroidism grew due to iodine deficiency (р = 0.012). The difference between pathological damage and prevalence of thyroid diseases reached 4.8–38.6 times. Having analyzed created logistic models, we were not able to identify sex or age as predictors of thyroid pathology occurrence.

Conclusion. Prevalence of thyroid pathology was established to be by 4.8–38.6 times lower than pathological damage. Iodine deficiency on a given territory calls for developing regional medical and prevention programs aimed at diagnosing and preventing thyroid diseases caused by it.

Neuropsychological Alterations in Patients with Congenital Hypothyroidism Treated with Levothyroxine: Linked Factors and Thyroid Hormone Hyposensitivity

Eighty-five percent of the studies of patients with congenital hypothyroidism (CH) treated with Levothyroxine (L-T₄) report neuropsychological sequelae throughout life. In neonates and infants, there is a deficit in sensorimotor skills (impaired balance). In preschool and elementary school children and adolescents, there are alterations in intellectual quotient (low scores), language (delayed phonological acquisition), memory (visual, verbal, visuospatial, visuoconstructive, autobiographical, and semantic), sensorimotor skills (impaired fine and gross motor control), and visuoconstructive–visuospatial domain (low scores in spatial location, block design, and object assembly). These neuropsychological domains are also affected in young adults, except for language (adequate verbal fluency) and visuoconstructive–visuospatial domain (no data). The onset and severity of neuropsychological sequelae in patients with treated CH depend on several factors: extrinsic, related to L-T₄ treatment and social aspects, and intrinsic, such as severity and etiology of CH, as well as structural and physiological changes in the brain. In this review, we hypothesized that thyroid hormone hyposensitivity (THH) could also contribute to neuropsychological alterations by reducing the effectiveness of L-T₄ treatment in the brain. Thus, further research could approach the THH hypothesis at basic and clinical levels to implement new endocrinological and neuropsychological therapies for CH patients.

Helicobacter pylori Infection Is Associated With Thyroid Dysfunction in Children With Congenital Hypothyroidism

Helicobacter pylori (H. pylori) infection leads to a systemic low-grade inflammatory state and has been associated causally with a diverse spectrum of extra-gastric disorders. Among them, the infection has been involved in the pathogenesis of autoimmune thyroid disease (ATD), but only one study had evaluated children. Therefore, a cross-sectional study was conducted in a cohort of 142 children and adolescents, randomly assessed among those followed up for thyroid diseases in a university pediatric endocrinology service: 106 with congenital hypothyroidism (CH) and 36 with ATD. All children were asymptomatic, under strict control on levothyroxine replacement, and reported no other diseases or use of drugs. Helicobacter pylori status was evaluated by the ¹³C-Urea Breath Test (¹³C-UBT). Antithyroid antibodies (ATPO, antiTg, and TRAb) and serum thyroid hormones (TSH, free T4, and T3) were assessed by standard assays. Data were analyzed in logistic models by the SPSS statistical software package, and a p-value ≤ 0.05 was considered statistically significant. The prevalence of H. pylori infection was 19.44% in children with ATD. Neither the gender nor the serum levels of thyroid hormones and antithyroid antibodies were associated with the H. pylori-positive status. Thirty-seven (34.90%) children with CH were infected with H. pylori. The mean T3 serum level (3.59 ± 0.84) was significantly lower (p = 0.001) in the infected children than in those free from the infection (3.95 ± 0.89), association that remained after adjustment for the other variables in the multivariate analysis. Because no difference was observed in the levels of TSH and T4, the results indicate that the infection may lead to impairment in the thyroid hormonal balance, but not in the hypothalamic-pituitary-thyroid axis function. In as much as H. pylori infection is highly widespread and the prevalence of CH is also not negligible, additional studies are required to confirm our results and to identify the involved mechanisms.

Leptin Does Not Influence TSH Levels in Obese Short Children

INTRODUCTION

Growth hormone (GH) and thyroid hormones are important for children growing. In some obese children a slightly elevated TSH concentration is observed. This may be an adaptive mechanism: stimulation of pro-TRH biosynthesis in the hypothalamus in response to elevated leptin. The increased TSH may also reflect the necessity of maintaining the resting energy expenditure or may be a result of inappropriate, low FT4 concentration. Thus, we evaluated serum TSH and FT4 concentrations in idiopathic short stature (ISS) children (non GH-deficient) and examined the effect of children's nutritional status and levels of selected adipocytokines on thyroid function, searching for the presence of various forms of subclinical hypothyroidism, which may be the cause of the slow growth rate.

METHODS

The study group included 115 children (50 girls and 65 boys) with ISS, aged (mean ± SD) 10.4 ± 3.34 years. In each child, lipids, TSH, FT4, IGF-1, maxGH during the stimulation tests, leptin, adiponectin and resistin concentrations were determined. Based on BMI SDS, 3 subgroups: slim (n=26), obese (n=21) and normal weight (n=68) were distinguished.

RESULTS

There was no correlation between leptin level and TSH, FT4 levels. The levels of leptin, total cholesterol and LDL-cholesterol in obese short children were significantly higher than in children from other subgroups. In turn, the levels of adiponectin, resistin, TSH and FT4 did not differ between subgroups. In 7% of children, an elevated TSH level was found (but less than 10 mIU/L), with a similar frequency across subgroups. The higher the leptin, the lower maxGH in clonidine stimulation test was recorded.

CONCLUSIONS

It seems that in obese children with idiopathic short stature leptin does not increase TSH secretion. This may be related to a disruption of the effect of leptin on TSH production and could indicate wide ranging disturbances of hypothalamic signals, and consequently be the cause of inappropriate GH secretion.

-

Congenital hypothyroidism is one of the common diseases causing delayed intelligence development and growth retardation in children. In 2021, the ENDO-European Reference Network updated the practice guidelines for the diagnosis and management of congenital hypothyroidism. The guidelines give a comprehensive and detailed description of the screening, diagnosis, and management of congenital hypothyroidism in neonates. This article gives an interpretation of the guidelines in order to provide a reference for clinicians in China.

Active Surveillance in RET Gene Carriers Belonging to Families with Multiple Endocrine Neoplasia

Simple Summary

MEN2 has a very high penetrance for the development of medullary thyroid cancer. However, intra- and inter-familial variabilities have been described. Accordingly, in this precision medicine era, a personalized approach should be adopted in subjects harboring RET mutations. In these subjects, we showed that thyroid surgery could be safely timed according to basal and stimulated calcitonin, especially in children who can reach adulthood, avoiding the risks of thyroid surgery and decreasing the period of a long-life hypothyroidism treatment.

Abstract

Multiple Endocrine Neoplasia 2 (MEN2) is a hereditary cancer syndrome for developing medullary thyroid cancer (MTC) due to germline mutations of RET gene. Subjects harboring a germline RET mutation without any clinical signs of MTC are defined as gene carriers (GCs), for whom guidelines propose a prophylactic thyroid surgery. We evaluate if active surveillance of GCs, pursuing early thyroid surgery, can be safely proposed and if it allows safely delaying thyroid surgery in children until adolescence/adulthood. We prospectively followed 189 GCs with moderate or high risk germline RET mutation. Surgery was planned in case of: elevated basal calcitonin (bCT) and/or stimulated CT (sCT); surgery preference of subjects (or parents, if subject less than 18 years old); other reasons for thyroid surgery. Accordingly, at RET screening, we sub-grouped GCs in subjects who promptly were submitted to thyroid surgery (Group A, n = 67) and who were not (Group B, n = 122). Group B was further sub-grouped in subjects who were submitted to surgery during their active surveillance (Group B1, n = 22) and who are still in follow-up (Group B2, n = 100). Group A subjects presented significantly more advanced age, bCT and sCT compared to Group B. Mutation RET^V804M was the most common variant in both groups but it was significantly less frequent in Group A than B. Analyzing age, bCT, sCT and genetic landscape, Group B1 subjects differed from Group B2 only for sCT at last evaluation. Group A subjects presented more frequently MTC foci than Group B1. Moreover, Group A MTCs presented more aggressive features (size, T and N) than Group B1. Accordingly, at the end of follow-up, all Group B1 subjects presented clinical remission, while 6 and 12 Group A MTC patients had structural and biochemical persistent disease, respectively. Thank to active surveillance, only 13/63 subjects younger than 18 years at RET screening have been operated on during childhood and/or adolescence. In Group B1, three patients, while actively surveilled, had the possibility to reach the age of 18 (or older) and two patients the age of 15, before being submitted to thyroid surgery. In Group B2, 12 patients become older than 18 years and 17 older than 15 years. In conclusion, we demonstrated that an active surveillance pursuing an early thyroid surgery could be safely recommended in GCs. This patient-centered approach permits postponing thyroid surgery in children until their adolescence/adulthood. At the same time, we confirmed that genetic screening allows finding hidden MTC cases that otherwise would be diagnosed much later.

Processing of Positive Newborn Screening Results for Congenital Hypothyroidism: A Qualitative Exploration of Current Practice in England

The objective of this research was to explore current communication practices for positive newborn bloodspot screening results for congenital hypothyroidism from the newborn bloodspot screening laboratory to clinicians and then families, in order to (i) understand how the pathway is implemented in practice, (ii) highlight regional differences and (iii) identify barriers and facilitators. A qualitative exploratory design was employed using semi-structured interviews across 13 newborn bloodspot screening laboratories in England. Participants included 35 clinicians and 17 NBS laboratory staff across the 13 laboratories and 18 members of relevant clinical teams. Findings illuminated variations in how positive newborn bloodspot screening results for congenital hypothyroidism are communicated in practice. This included regional variations due to historical arrangements and local resources. Contacting the appropriate person could be challenging and obtaining feedback from clinical teams to the laboratory after the child has been seen could be time consuming for those involved. Standardised communication model(s) for positive newborn bloodspot screening results for congenital hypothyroidism, which include named contact individuals, defined pathways of care and processes for feeding back to laboratories, may help to ensure the process is less labour intensive, particularly from a laboratory perspective.

Age- and sex-specific reference intervals for thyroid hormones in a Chinese pediatrics: a prospective observational study of 1,279 healthy children

BACKGROUND

Thyroid hormones are essential for early neurocognitive development and growth and development in childhood and adolescence. However, the reference intervals (RIs) for thyroid hormones in Chinese pediatric individuals remain unclear. This study aimed to establish thyroid hormone RIs for a Chinese pediatric population according to appropriate age- and sex-specific partitioning.

METHODS

In this prospective observational study, a total of 1,279 healthy children (singletons, aged from 1 day to 12 years) were recruited, and serum samples were analyzed on a Mindray automated chemiluminescence immunoassay analyzer CL-6000i for thyroid hormone detection, including thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), total triiodothyronine (T3), and total thyroxine (T4). Age and sex-specific RIs were established, and the corresponding 95% confidence intervals (CIs) were calculated in accordance with the Clinical Laboratory Standards Institute (CLSI) document C28-A3 guidelines.

RESULTS

Quantile testing revealed that the median (P50) and RIs [2.5^th percentile (P2.5)-97.5^th percentile (P97.5)] for TSH, FT3, T3, and T4 of males differed significantly from those of females (P<0.05), except for FT4 (P=0.483). For FT3 and T3, the RIs of males were higher than that of females, and the RI of T4 for males was narrower and higher than that of females [P2.5-P97.5: 72.33-171.60 vs. 72.31-176.27 nmol/L; P50: 116.75 vs. 113.47 nmol/L, P=0.011]. RIs for TSH, FT3, FT4, T3, and T4 showed sex- and age-specific properties and displayed a wide variation during the first month of life but gradually narrowed and concentrated with increasing age. In addition, RIs of TSH, FT3, FT4, and T3 in males differed significantly from females in the first month of life (TSH: 1.46-10.87 vs. 1.08-11.35 mIU/L; FT3: 2.96-7.08 vs. 2.35-7.27 pmol/L, FT4: 13.34-28.65 vs. 13.82-31.83 pmol/L; T3: 0.83-2.33 vs. 0.72-2.46 nmol/L). The RI of T4 also exhibited a difference between males and females in the 9- to 12-year age group (59.31-150.72 vs. 63.29-146.94 pmol/L for males and females, respectively).

CONCLUSIONS

Pediatric RIs of thyroid hormones display age- and sex-specific trends. The RIs established in this study will improve the accuracy of TSH assay result interpretations and clinical decision-making in clinical laboratories that utilize the Mindray analytical platform.

Mediastinal ectopic thyroid tissue, an imitator of an enlarged lymph node with metastatic pulmonary neoplasia

The prevalence of ectopic thyroid tissue, based on autopsy studies, is between 7% and 10%, but there are rare cases reported in the thoracic region. Here, we encountered a case of thoracic ectopic thyroid tissue presenting as a presumed enlarged mediastinal lymph node. A 50-year-old female with a history of lung adenocarcinoma, status post resection, presented with complaints of headache, dizziness, and nausea. Magnetic resonance imaging found two brain lesions consistent with metastasis. Computed tomography scan showed enlarged mediastinal lymph nodes and thyroid nodules. Fine-needle aspiration (FNA) of one thyroid nodule was positive for papillary thyroid carcinoma. FNA of the mediastinal lymph nodes were negative for metastatic carcinoma but revealed thyroid tissue in the 2.9 × 1.6 cm presumed 2 L lymph node. The morphological features and immunohistochemical stains confirmed thyroid tissue, and there were no cytological features of thyroid carcinoma. In patients with a history of a pulmonary tumor (such as adenocarcinoma, low-grade neuroendocrine tumor), ectopic thyroid tissue, although a rare event, could represent a pitfall in the cytologic evaluation of mediastinal lymph nodes aspirates obtained from staging procedures. Careful morphologic examination with a panel of immunohistochemical studies are useful in making the correct diagnosis, leading to appropriate patient management.

Neonatal Dyshormonogenetic Goiter with Hypothyroidism Associated with Novel Mutations in Thyroglobulin and SLC26A4 Gene

Congenital goiter is an uncommon cause of neck swelling and it can be associated with hypothyroidism. We discuss a case of primary hypothyroidism with goiter presenting at birth. Ultrasound showed the enlargement of the gland and thyroid function tests detected marked hypothyroidism. Genetic analysis via next generation sequencing (NGS) was performed finding two mutations associated with thyroid dyshormonogenesis: c.7813 C > T, homozygous in the exon 45 of the thyroglobulin gene (TG) and c.1682 G > A heterozygous in exon 15 of the SLC26A4 gene (pendrin). Sanger sequencing of parents' DNA samples revealed that the first mutation (c.7813 C > T) was inherited from both of them, while the second one (c.1682 G > A) was inherited from the mother. Hormone replacement therapy was started, following which a gradual decrease in the size of the goiter was seen with the normalization of hormonal levels. Normal infant growth status and neurological development were recorded during follow-up. Neonatal dyshormonogenetic goiter with hypothyroidism may represent an unusual cause of neonatal neck mass. Early identification and hormone replacement therapy are crucial for a better neurodevelopmental outcome. Genetic analysis is mandatory in order to reach a specific diagnosis and to elucidate new patterns of thyroid disorder.

Transient Hyperthyrotropinemia in Outpatient Children with Acute Infections of the Respiratory System

Background: Diagnostics of thyroid disorders (TD) are frequently based on the measurements of thyroid stimulating hormone (TSH) concentration only. If TSH is outside the reference range, the diagnostic procedure used in patients with TD isintroduced. Observations indicate that in a considerable number of these patients, TD is not confirmed. The aim of the study was to assess the incidence of transient hyperthyrotropinemia in healthy children during acute infections of the respiratory system. Patients and Methods: The study included consecutive children (49 boys and 45 girls), aged 2.2–17.3 years, who visited one General Practitioner (GP) due to respiratory tract infections. The tests: complete blood count (CBC), C-reactive protein (CRP), TSH and FT4 were run on the next day after the visit at the physician’s (initial visit) and ≥2 weeks after recovery. Results: Among these children, elevated TSH values were found in about 10% of patients, and they went back to normal values after recovery. A prospective analysis showed a reduction of TSH values in approx. 65% of all groups and TSH at the follow-up visit was significantly lower. Conclusions: Transient hyperthyrotropinemia was observed in about 10% of children with acute respiratory tract infection. This preliminary finding remains unexplained.

Paediatrics: how to manage functional constipation

BACKGROUND

Despite being a common problem in childhood, functional constipation is often difficult to manage. This article provides a narrative updated review on the evaluation, diagnosis and management of childhood functional constipation.

METHODS

A PubMed search was performed with Clinical Queries using the key term 'functional constipation'. The search strategy included clinical trials, meta-analyses, randomized controlled trials, observational studies and reviews. The search was restricted to the English literature and to the paediatric population. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

A detailed history and thorough physical examination are important in the evaluation of a child with constipation to establish the diagnosis of functional constipation as per the Rome IV criteria and to catch 'red flags' suggestive of organic causes of constipation. These 'red flags' include delayed passage of meconium, ribbon stool, rectal bleeding/blood in the stool unless attributable to an anal fissure, failure to thrive, severe abdominal distension, absent anal wink/cremasteric reflex, tight and empty rectum on digital examination and explosive expulsion of liquid stool and gas on withdrawal of the finger, hair tuft/dimple/lipoma/haemangioma in the lumbosacral area, and an anteriorly displaced anus. For functional constipation, pharmacological therapy consists of faecal disimpaction and maintenance therapy. This can be effectively accomplished with oral medications, rectal medications or a combination of both. The most commonly used and most effective laxative is polyethylene glycol. Non-pharmacological management consists of education, behavioural modification and dietary interventions. The combination of pharmacological therapy and non-pharmacological management increases the chance of success.

CONCLUSION

Polyethylene glycol is the medication of first choice for both disimpaction and maintenance therapy. If polyethylene glycol is not available or is poorly tolerated, lactulose is the preferred alternative. Other laxatives may be considered as second-line therapy if treatment with osmotic laxatives fails or is insufficient. Maintenance treatment should be continued for at least 2 months. Early treatment will result in a faster and shorter treatment course.

Congenital Hypothyroidism: A 2020-2021 Consensus Guidelines Update-An ENDO-European Reference Network Initiative Endorsed by the European Society for Pediatric Endocrinology and the European Society for Endocrinology

Background: An ENDO-European Reference Network (ERN) initiative was launched that was endorsed by the European Society for Pediatric Endocrinology and the European Society for Endocrinology with 22 participants from the ENDO-ERN and the two societies. The aim was to update the practice guidelines for the diagnosis and management of congenital hypothyroidism (CH). A systematic literature search was conducted to identify key articles on neonatal screening, diagnosis, and management of primary and central CH. The evidence-based guidelines were graded with the Grading of Recommendations, Assessment, Development and Evaluation system, describing both the strength of recommendations and the quality of evidence. In the absence of sufficient evidence, conclusions were based on expert opinion. Summary: The recommendations include the various neonatal screening approaches for CH as well as the etiology (also genetics), diagnostics, treatment, and prognosis of both primary and central CH. When CH is diagnosed, the expert panel recommends the immediate start of correctly dosed levothyroxine treatment and frequent follow-up including laboratory testing to keep thyroid hormone levels in their target ranges, timely assessment of the need to continue treatment, attention for neurodevelopment and neurosensory functions, and, if necessary, consulting other health professionals, and education of the child and family about CH. Harmonization of diagnostics, treatment, and follow-up will optimize patient outcomes. Lastly, all individuals with CH are entitled to a well-planned transition of care from pediatrics to adult medicine. Conclusions: This consensus guidelines update should be used to further optimize detection, diagnosis, treatment, and follow-up of children with all forms of CH in the light of the most recent evidence. It should be helpful in convincing health authorities of the benefits of neonatal screening for CH. Further epidemiological and experimental studies are needed to understand the increased incidence of this condition.

Derivation of Thyroid Follicular Cells From Pluripotent Stem Cells: Insights From Development and Implications for Regenerative Medicine

Stem cell-based therapies to reconstitute in vivo organ function hold great promise for future clinical applications to a variety of diseases. Hypothyroidism resulting from congenital lack of functional thyrocytes, surgical tissue removal, or gland ablation, represents a particularly attractive endocrine disease target that may be conceivably cured by transplantation of long-lived functional thyroid progenitors or mature follicular epithelial cells, provided a source of autologous cells can be generated and a variety of technical and biological challenges can be surmounted. Here we review the emerging literature indicating that thyroid follicular epithelial cells can now be engineered in vitro from the pluripotent stem cells (PSCs) of mice, normal humans, or patients with congenital hypothyroidism. We review the in vivo embryonic development of the thyroid gland and explain how emerging discoveries in developmental biology have been utilized as a roadmap for driving PSCs, which resemble cells of the early embryo, into mature functional thyroid follicles in vitro. Finally, we discuss the bioengineering, biological, and clinical hurdles that now need to be addressed if the goals of life-long cure of hypothyroidism through cell- and/or gene-based therapies are to be attained.

Thyroid disrupting chemicals and developmental neurotoxicity - New tools and approaches to evaluate hormone action

It is well documented that thyroid hormone (TH) action is critical for normal brain development and is mediated by both nuclear and extranuclear pathways. Given this dependence, the impact of environmental endocrine disrupting chemicals that interfere with thyroid signaling is a major concern with direct implications for children's health. However, identifying thyroid disrupting chemicals in vivo is primarily reliant on serum thyroxine (T4) measurements within greater developmental and reproductive toxicity assessments. These studies do not examine known TH-dependent phenotypes in parallel, which complicates chemical evaluation. Additionally, there exist no recommendations regarding what degree of serum T4 dysfunction is adverse, and little consideration is given to quantifying TH action within the developing brain. This review summarizes current testing strategies in rodent models and discusses new approaches for evaluating the developmental neurotoxicity of thyroid disrupting chemicals. This includes assays to identify adverse cellular effects of the brain by both immunohistochemistry and gene expression, which would compliment serum T4 measures. While additional experiments are needed to test the full utility of these approaches, incorporation of these cellular and molecular assays could enhance chemical evaluation in the regulatory arena.

Upper and Lower Limb Strength and Body Posture in Children with Congenital Hypothyroidism: An Observational Case-Control Study

BACKGROUND

Congenital hypothyroidism (CH) is an endocrine disease with a precocious significant impairment of growth and neuromotor development. Thyroid hormones are essential for central nervous system development, maturation, and myelination. Furthermore, thyroid hormone deficiency affects the function of several systems, including the musculoskeletal system. The disease has a significant incidence in the general population (1:3000-1:2000 newborns in Italy). The aim of the present study was to evaluate any differences in upper and lower limb strength, body sway, and plantar loading distribution in children with CH compared to healthy children.

METHODS

In this study, the case group was composed of children with CH (CHG), while the control group included healthy children (CG). Both groups comprised 19 children (CHG: female = 12; CG: female = 9). The maximum isometric handgrip strength and explosive-elastic lower limb strength were assessed with the handgrip test and the Sargent test, respectively. The stabilometric and baropodometric analyses were used to measure the Center of Pressure displacements and the plantar loading distribution between feet, respectively. The differences between groups were analyzed by a univariate analysis of covariance using as covariates weight and height with the significant level set at < 0.05.

RESULTS

We found that CHG children were shorter and thinner than CG ones (p < 0.05). No significant difference in the upper and lower limb strength was found between groups. CHG exhibited a significant greater Sway Path Length (p < 0.01) and Ellipse Surface (p < 0.05) than CG. Moreover, CHG displayed an asymmetric plantar loading distribution with a significant lower percentage in the right than in the left foot (p < 0.05). Moreover, a significant lower plantar loading percentage in the right foot of CHG than in the right foot of CG was observed (p < 0.05).

CONCLUSIONS

These findings seem to suggest that CH does not affect muscle strength in early treated children. However, these patients show poor postural control ability and asymmetric plantar loading distribution. Increasing the physical activity in these children could improve their body posture.

Interference on Iodine Uptake and Human Thyroid Function by Perchlorate-Contaminated Water and Food

BACKGROUND

Perchlorate-induced natrium-iodide symporter (NIS) interference is a well-recognized thyroid disrupting mechanism. It is unclear, however, whether a chronic low-dose exposure to perchlorate delivered by food and drinks may cause thyroid dysfunction in the long term. Thus, the aim of this review was to overview and summarize literature results in order to clarify this issue.

METHODS

Authors searched PubMed/MEDLINE, Scopus, Web of Science, institutional websites and Google until April 2020 for relevant information about the fundamental mechanism of the thyroid NIS interference induced by orally consumed perchlorate compounds and its clinical consequences.

RESULTS

Food and drinking water should be considered relevant sources of perchlorate. Despite some controversies, cross-sectional studies demonstrated that perchlorate exposure affects thyroid hormone synthesis in infants, adolescents and adults, particularly in the case of underlying thyroid diseases and iodine insufficiency. An exaggerated exposure to perchlorate during pregnancy leads to a worse neurocognitive and behavioral development outcome in infants, regardless of maternal thyroid hormone levels.

DISCUSSION AND CONCLUSION

The effects of a chronic low-dose perchlorate exposure on thyroid homeostasis remain still unclear, leading to concerns especially for highly sensitive patients. Specific studies are needed to clarify this issue, aiming to better define strategies of detection and prevention.

DUOX2 and DUOXA2 Variants Confer Susceptibility to Thyroid Dysgenesis and Gland-in-situ With Congenital Hypothyroidism

Background: Thyroid dysgenesis (TD), which is caused by gland developmental abnormalities, is the most common cause of congenital hypothyroidism (CH). In addition, advances in diagnostic techniques have facilitated the identification of mild CH patients with a gland-in-situ (GIS) with normal thyroid morphology. Therefore, TD and GIS account for the vast majority of CH cases. Methods: Sixteen known genes to be related to CH were sequenced and screened for variations by next-generation sequencing (NGS) in a cohort of 377 CH cases, including 288 TD cases and 89 GIS cases. Results: In our CH cohort, we found that DUOX2 (21.22%) was the most commonly variant pathogenic gene, while DUOXA2 was prominent in TD (18.75%) and DUOX2 was prominent in GIS (34.83%). Both biallelic and triple variants of DUOX2 were found to be most common in children with TD and children with GIS. The most frequent combination was DUOX2 with DUOXA1 among the 61 patients who carried digenic variants. We also found for the first time that biallelic TG, DUOXA2, and DUOXA1 variants participate in the pathogenesis of TD. In addition, the variant p.Y246X in DUOXA2 was the most common variant hotspot, with 58 novel variants identified in our study. Conclusion: We meticulously described the types and characteristics of variants from sixteen known gene in children with TD and GIS in the Chinese population, suggesting that DUOXA2 and DUOX2 variants may confer susceptibility to TD and GIS via polygenic inheritance and multiple factors, which further expands the genotype-phenotype spectrum of CH in China.

Childhood Alopecia Areata: An Overview of Treatment and Recent Patents

BACKGROUND

Alopecia Areata (AA) is a systemic autoimmune condition that usually starts in childhood.

OBJECTIVE

This article aims to review genetics, therapy, prognosis, and recent patents for AA.

METHODS

We used clinical queries and keywords "alopecia areata" AND "childhood" as a search engine. Patents were searched using the key term "alopecia areata" in Patents.google.com and freepatentsonline. com.

RESULTS

Due to an immune-mediated damage to the hair follicles, hair is lost from the scalp and other areas of the body temporarily or even permanently. Children with AA are generally healthy. Evidence of genetic association and increased predisposition for AA was found by studying families with affected members. Pathophysiologically, T- lymphocytes attack hair follicles and cause inflammation and destruction of the hair follicles and hair loss. In mild cases, there would be well-demarcated round patchy scalp hair loss. The pathognomonic "exclamation mark hairs" may be seen at the lesion periphery. In more severe cases, the hair loss may affect the whole scalp and even the whole body. The clinical course is also variable, which may range from transient episodes of recurrent patchy hair loss to an indolent gradually deteriorating severe hair loss. The treatment of AA depends on factors including patients' age, the extent of the hair loss, duration of disease, psychological impact, availability and side effect profile of the treatments. For localized patchy alopecia, topical application of corticosteroids and/or intralesional corticosteroids are the treatment of choice. Other topical treatments include minoxidil, anthralin, coal tar and immunotherapy. In severe resistant cases, systemic immunosuppressants may be considered. Although herbal medicine, acupuncture, complementary and alternative medicine may be tried on children in some Asian communities, the evidence to support these practices is lacking. To date, only a few recent patents exist in topical treatments, including Il-31, laser and herbal medications. Clinical efficacy is pending for these treatment modalities.

CONCLUSION

None of the established therapeutic options are curative. However, newer treatment modalities, including excimer laser, interleukin-31 antibodies and biologics, are evolving so that there may be significant advances in treatment in the near future. AA can be psychosocially devastating. It is important to assess the quality of life, degree of anxiety, social phobia and mood of the patients and their families. Psychological support is imperative for those who are adversely affected psychosocially.

Childhood Langerhans cell histiocytosis: a disease with many faces

BACKGROUND

Langerhans cell histiocytosis (LCH) is a group of diseases characterized by the proliferation and accumulation of Langerhans cells. Clinical presentations of LCH vary widely.

DATA SOURCES

A PubMed search was conducted using Clinical Queries with the key term "Langerhans cell histiocytosis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. This paper is based on, but not limited to, the search results.

RESULTS

Generally, patients with LCH can be divided into two groups based on the extent of involvement at diagnosis, namely, single-system LCH and multisystem LCH. The involvement may be unifocal or multifocal. Patients with isolated bone lesions typically present between 5 and 15 years of age, whereas those with multisystem LCH tend to present before 5 years of age. The clinical spectrum is broad, ranging from an asymptomatic isolated skin or bone lesion to a life-threatening multisystem condition. Clinical manifestations include, among others, "punched out" lytic bone lesion, seborrheic dermatitis-like eruption, erythematous/reddish-brown crusted/scaly papules/maculopapules/plaques/patches, and eczematous lesions, diabetes insipidus, hepatosplenomegaly, cytopenias, lymphadenopathy, and an acute fulminant disseminated multisystem condition presenting with fever, skin rash, anemia, thrombocytopenia, lymphadenopathy, and hepatosplenomegaly. The diagnosis is clinicopathologic, based on typical clinical findings and histologic/immunohistochemical examination of a biopsy of lesional tissue. Positive CD1a, S100, and/or CD207 (Langerin) immunohistochemical staining of lesional cells is required for a definitive diagnosis. Watchful waiting is recommended for patients with skin-only LCH. Patients with symptomatic or refractory skin-only LCH may be treated with topical tacrolimus/corticosteroids, topical nitrogen mustard, oral methotrexate, or oral hydroxyurea. The current recommended first-line therapy for patients with multisystem LCH is 12 months therapy with prednisone and vinblastine. Mercaptopurine is added for patients with risk organ involvements.

CONCLUSIONS

Because of the broad spectrum of clinical manifestations and the extreme diversity of disease, LCH remains a diagnostic dilemma. Morphological identification of LCH cells and positive immunochemical staining with CD1a, S100, and/or CD207 (Langerin) of lesional cells are necessary for a definitive diagnosis.

Individualised requirements for optimum treatment of hypothyroidism: complex needs, limited options

Levothyroxine (LT4) therapy has a long history, a well-defined pharmacological profile and a favourable safety record in the alleviation of hypothyroidism. However, questions remain in defining the threshold for the requirement of treatment in patients with subclinical hypothyroidism, assessing the dose adequacy of the drug, and selecting the best treatment mode (LT4 monotherapy versus liothyronine [LT3]/LT4 combinations) for subpopulations with persisting complaints. Supplied as a prodrug, LT4 is enzymatically converted into the biologically more active thyroid hormone, triiodothyronine (T3). Importantly, tetraiodothyronine (T4) to T3 conversion efficiency may be impaired in patients receiving LT4, resulting in a loss of thyroid-stimulating hormone (TSH)-mediated feed-forward control of T3, alteration of the interlocking equilibria between serum concentrations of TSH, free thyroxine (FT4), and free triiodothyonine (FT3), and a decrease in FT3 to FT4 ratios. This downgrades the value of the TSH reference system derived in thyroid health for guiding the replacement dose in the treatment situation. Individualised conditionally defined setpoints may therefore provide appropriate biochemical targets to be clinically tested, together with a stronger focus on clinical presentation and future endpoint markers of tissue thyroid state. This cautionary note encompasses the use of aggregated statistical data from clinical trials which are not safely applicable to the individual level of patient care under these circumstances.