A global perspective on newborn congenital hypothyroidism screening

Experiences and Challenges with Congenital Hypothyroidism Newborn Screening in Indonesia: A National Cross-Sectional Survey

The expansion of newborn screening (NBS) for congenital hypothyroidism (CH) is essential to reducing the number of preventable intellectual disabilities in children. Because of logistical issues, including geographic extremes, distinct cultures, and 4.8 million births annually, Indonesia has struggled to achieve universal NBS coverage. A national cross-sectional electronic survey was conducted to explore challenges in CH NBS. Responses from 423 healthcare professionals and program administrators across 30 provinces in Indonesia were collected. The major challenges reported were refusal from families (39.2%), newborns being discharged <24 h (38.3%), and limited availability of filter paper (35.9%). The respondents considered refusal from families to be due to fear, while others did not understand the necessity of CH NBS. The vast majority of respondents believed that parents do not have sufficient understanding regarding CH NBS (96.5%). Our study found that only 38.5% of respondents had received formal CH NBS training, with pediatric endocrinologists being the only profession in which all respondents had been trained. Concerted efforts are needed to improve the access to and availability of resources, increase the capacity for sample collection and analysis, empower healthcare professionals, and develop educational resources to promote understanding and acceptance of NBS amongst families.

Effects of low-dose levothyroxine on atrial natriuretic peptide and c-type natriuretic peptide in children with neonatal hypothyroidism

OBJECTIVE

This study was designed to explore the effects of low-dose levothyroxine (LT4) on levels of atrial natriuretic peptide (ANP) and c-type natriuretic peptide (CNP) in neonates with hypothyroidism (NH).

METHODS

In this retrospective study, a total of 90 cases of NH screened out and confirmed by the First Affiliated Hospital of Zhejiang Chinese Medical University from October 2014 to February 2018 were selected as a study group. 80 healthy children who underwent physical examination during the same time period were enrolled as controls. Before and after treatment with LT4, the changes in the levels of serum thyroid stimulating hormone (TSH) and free thyroxine (FT4) were observed, and the changes in the levels of ANP and CNP and their relationships to clinical efficacy were evaluated. Additionally, the growth and development of body and the scores of the China-Wechsler Younger Children Scale of Intelligence (C-WYCSI) were compared before and after the treatment, and the changes in the cardiac functions of children in the study group were evaluated. Independent risk factors for mental abnormality after treatment were analyzed by logistic regression.

RESULTS

After treatment, TSH levels in patients declined, while the levels of T3, T4, free triiodothyronine (FT3), and FT4 increased, without significant differences between groups. After treatment, ANP levels in patients increased but CNP levels decreased. ANP levels were negatively correlated with clinical efficacy, but CNP levels were positively correlated with it. Ultrasonic cardiography showed the improved cardiac functions. After treatment, the growth and development of body and the C-WYCSI scores increased compared to those before treatment. First visit date, T3, FT4, TSH were independent risk factors for mental disorders in children.

CONCLUSION

For children with NH, low-dose LT4 can correct the level of thyroid function, promote physical and mental development, and improve the levels of ANP and CNP.

Thyroid hormone action during GABAergic neuron maturation: The quest for mechanisms

Thyroid hormone (TH) signaling plays a major role in mammalian brain development. Data obtained in the past years in animal models have pinpointed GABAergic neurons as a major target of TH signaling during development, which opens up new perspectives to further investigate the mechanisms by which TH affects brain development. The aim of the present review is to gather the available information about the involvement of TH in the maturation of GABAergic neurons. After giving an overview of the kinds of neurological disorders that may arise from disruption of TH signaling during brain development in humans, we will take a historical perspective to show how rodent models of hypothyroidism have gradually pointed to GABAergic neurons as a main target of TH signaling during brain development. The third part of this review underscores the challenges that are encountered when conducting gene expression studies to investigate the molecular mechanisms that are at play downstream of TH receptors during brain development. Unravelling the mechanisms of action of TH in the developing brain should help make progress in the prevention and treatment of several neurological disorders, including autism and epilepsy.

Prosthodontic Management of Congenital Hypothyroidism with Anodontia: A Case Report

Thyroid dysfunction has various manifestations which include orofacial abnormalities like delayed eruption, retained deciduous teeth, etc. Early detection of this deregulation of thyroid homeostasis can prevent associated complications. This report is a case of congenital hypothyroidism (CH) in a 4-year-old boy who presented with a completely edentulous maxilla and hypodontic mandible. Based on various biochemical and radiographic investigations, a diagnosis of CH was established. He was prosthodontically rehabilitated with removable dentures.

How to cite this article: Bhat V, Bhat VS, Vadakkan J, et al. Prosthodontic Management of Congenital Hypothyroidism with Anodontia: A Case Report. Int J Clin Pediatr Dent 2021;14(4):586–589.

Congenital Hypothyroidism

Congenital hypothyroidism (CH) is a disorder of thyroid hormone deficiency which develops secondary to incomplete thyroid development or inadequate thyroid hormone production. State-mandated newborn screening throughout the United States has increased the detection rate of CH, allowing for early intervention. Although the overall mortality rate of CH is low, delayed or omitted treatment can lead to devastating neurocognitive outcomes. As such, CH is regarded as the leading cause of preventable intellectual disability in children. Early identification, facilitated by astute neonatal nursing and medical care, is contingent upon an active working knowledge of the disease process and awareness of the limitations of the newborn screen.

First Experiences with Newborn Screening for Congenital Hypothyroidism in Ulaanbaatar, Mongolia

Congenital hypothyroidism (CH) is among the most common conditions leading to intellectual disability, which can be prevented by early detection through newborn screening (NBS). In Mongolia, a regional screening program for CH was launched in 2000, which was supported by the International Atomic Energy Agency (IAEA) for the Asia Pacific Region. In our present study, a total of 23,002 newborns from nine districts in Ulaanbaatar were screened between 2012 and 2020, by the measurement of the thyroid-stimulating hormone (TSH) from dried blood spots, sampled 24 to 72 h after birth. The level of TSH was measured by the DELFIA assay. The overall CH prevalence confirmed at birth was 1/2091. The female-to-male ratio for CH cases was 1.8:1. The majority of patients were asymptomatic (72.7% of CH cases); umbilical hernia and cold or mottled skin were reported symptoms in patients with CH (27.3%). Thyroid dysgenesis (hypoplasia and agenesis) was the most common etiology, with a total of nine cases (81.8%) out of the eleven patients. The lapse between the birth date and the initiation of L-thyroxine treatment in CH-positive children was lower than 15 days in 63.64% of cases or 15 to 30 days in 36.36% of children. Further research is required to expand the screening coverage for CH in Mongolia.

Molecular and clinical characteristics of congenital hypothyroidism in a large cohort study based on comprehensive thyroid transcription factor mutation screening in Henan

BACKGROUND

Congenital hypothyroidism (CH), the most common neonatal endocrine disorder worldwide, can be caused by variants in thyroid transcription factor (TTF) genes including NKX2-1, FOXE1, PAX8, NKX2-5 and HHEX. This study aims to perform targeted next-generation sequencing (NGS) panel for comprehensive mutation screening on these genes in a cohort of 606 CH patients with various types from Henan Province, China, to investigate the mutation rate of TTF genes, and to analyze the clinical, biochemical and molecular characteristics of our CH cohort.

METHODS

High-throughput sequencing combined with statistical calculation were applied for mutation screening and analyses of the clinical data.

RESULTS

Twenty-two likely disease-causing monoallelic mutations in the TTF genes were identified in our cohort (3.63%, 22/606). Mutated PAX8 was the most predominant genetic alteration among these TTF mutations. Interestingly, PAX8 defects were only found in TD cases and variants in the five TTF genes were detected in gland in situ (GIS) patients. CH patients with the same genotype may have significant phenotypic variability and permanent CH (PCH) patients in the GIS group were significantly fewer than those in the TD group.

CONCLUSIONS

Our study showed the estimated TTF mutation rate among CH cases was 3.63% in Henan Province and genetic alternations in TTF genes played a role not only in TD but also in GIS, especially in goiter. Although we speculated that the five TTF genes may be involved in certain steps of thyroid hormone biosynthesis, more researches are needed to verify the conclusions of the present study.