Incidence of Congenital Hypothyroidism Over 37 Years in Ireland

Paediatric thyroid disease

The spectrum of thyroid disorders presenting to paediatricians is different to that seen by adult physicians. Referrals reflect cases detected by the neonatal screening programme for congenital hypothyroidism and many of the inherited defects of thyroid hormone generation or action will be manifest in early life. Autoimmune thyroid disease can be particularly challenging to manage in the young and the potential impact of thyroid status on neurodevelopment and schooling are key considerations throughout childhood and adolescence.

Hypothyroidism in Patients with Down Syndrome: Prevalence and Association with Congenital Heart Defects

This population-based study aimed to assess the prevalence of congenital hypothyroidism (CH) and overt hypothyroidism (OH) and their association with congenital heart defects (CHDs) in patients with Down syndrome (DS). The population included all live births residing in Tuscany (Italy) diagnosed with DS recorded in the Registry of Congenital Defects and in the Registry of Rare Diseases of Tuscany in the years 2003-2017. The prevalence of CH and OH in DS patients was calculated by sex and by period. The association of CH and OH with CHDs in DS patients was assessed using multivariate logistic regression. The cohort included 228 subjects. The prevalence of CH and OH was 11.4% (95%CI: 7.4-16.7%) and 12.7% (95%CI: 8.5-12.3%), respectively, with no significant difference by sex. A significant increase in the prevalence of CH (p < 0.0001) was found in the years 2010-2017 compared to the previous period, and among preterm infants (p = 0.009). The presence of CH was associated with a higher prevalence of CHDs (adjusted OR = 2.24, p = 0.082). A significant association between ventricular septal defects (VSDs) and the occurrence of OH (adjusted OR = 3.07, p = 0.025) was also observed. This study confirmed the higher prevalence of both CH and OH in DS compared to the general population. Furthermore, the risk of association between DS and CHDs was higher in the presence of CH, while VSDs are associated with OH, providing relevant insights into the epidemiology of hypothyroidism in DS and associated anomalies.

Quality of life and socioeconomic and educational status in patients with congenital hypothyroidism

BACKGROUND

The aim of this study was to investigate the influence of primary congenital hypothyroidism (CH) on quality of life, level of education and socioeconomic status (SES).

METHODS

Two independent study cohorts, a national and a regional, were collected from Finnish national registers and patient records. Data on social security benefits, SES, marital status, and education were collected from Statistics Finland. Health-related quality of life (HRQoL) was studied in the regional patient cohort with the standardized 15D and 16D instruments.

RESULTS

There were no statistically significant differences in education level, marital status, or SES between CH patients (n = 40) and their matched controls at the age of 25 years. The mean 15D score was both statistically significantly and clinically importantly lower in CH patients (n = 29) than controls (0.904 vs. 0.953, p = 0.008). CH patients reported significantly lower scores across various dimensions of physical and mental HRQoL, including breathing, sleeping, speech, excretion, mental function, distress, and vitality. The mean 16D score was lower in CH patients compared to controls (0.917, vs. 0.947), but without statistical significance.

CONCLUSION

SES of CH patients did not differ from matched controls. Thus, most CH patients integrate well into society, but their HRQoL is impaired.

IMPACT

Most patients with primary congenital hypothyroidism integrate well into society. In the current study, their socioeconomic and marital status did not differ from matched controls at the age of 25 years. However, health-related quality of life measured using 15D instrument was impaired. Every fourth patient reported that congenital hypothyroidism influenced everyday life.

History of Neonatal Screening of Congenital Hypothyroidism in Portugal

Congenital hypothyroidism (CH) leads to growth and development delays and is preventable with early treatment. Neonatal screening for CH was initiated in Portugal in 1981. This study examines the history of CH screening in the country. Data were obtained from annual reports and from the national database of neonatal screening laboratory. The CH screening strategy primarily relies on the thyroid-stimulating hormone (TSH), followed by total thyroxine measurement as the second tier for confirmation. The TSH cutoff started at 90 mIU/L, decreasing to the actual 10 mIU/L. The coverage of the screening program has increased rapidly; although voluntary, it reached about 90% in 6 years and became universal in 10 years. Guideline and cutoff updates led to the identification of over 200 additional cases, resulting in specific retesting protocols for preterm and very-low-birth-weight babies. The actual decision tree considers CH when TSH levels are above 40 mIU/L. Data from the CH screening also provide an indication of the iodine status of the population, which is presently indicative of iodine insufficiency. The Portuguese neonatal screening for CH is a history of success. It has rapidly and continuously adapted to changes in knowledge and has become a universal voluntary practice within a few years.

Results of neonatal screening for congenital hypothyroidism and hyperphenylalaninemia in Zhejiang province from 1999 to 2022

OBJECTIVES

To analyze the results of neonatal screening for congenital hypothyroidism (CH) and hyperphenylalaninemia (HPA) in Zhejiang province from 1999 to 2022.

METHODS

A total of 11 922 318 newborns were screened from September 1999 and December 2022 in Zhejiang province. The blood thyroid stimulating hormone (TSH) levels were measured by a fluorescence method and blood phenylalanine (Phe) levels were measured by fluorescence method or tandem mass spectrometry. TSH≥9 μIU/mL was considered positive for CH, while Phe>120 μmol/L and/or Phe/Tyr ratio>2.0 were considered positive for HPA. The positive newborns in screening were recalled, and the gene variations were detected by high-throughput sequencing and MassARRAY tests.

RESULTS

The overall neonatal screening rate during 1999-2022 was 89.41% (11 922 318/13 333 929) and the screening rate was increased from 6.46% in 1999 to 100.0% in 2022. A total of 8924 cases of CH were diagnosed among screened newborns with an incidence rate of 1/1336. A total of 563 cases of HPA were diagnosed, including 508 cases of classic phenylketonuria (cPKU) and 55 cases of tetrahydrobiopterin deficiency (BH4D), with an incidence rate of 1/21 176. Ninety-seven out of 8924 cases of CH underwent genetic analysis. Gene mutations were detected in 9 CH related genes, the highest frequency mutations were found in DUOX2 gene (69.0%) with c.3329G>A (p.R1110Q) (18.2%) and c.1588A>T (p.K530X) (17.3%) as the hotspot mutations. There were 81 PAH gene variants detected in a total of 250 cases of cPKU, and c728G>A (p.R243Q) (24.4%), c.721C>T (p.R241C) (15.0%) were the hotspot mutations. Meanwhile 7 novel variants in PAH gene were detected: c.107C>A (p.S36*), c.137G>T (p.G46V), c.148A>G(p.K50E), c.285C>T (p.I95I), c.843-10delTTCC, exon4-7del and c.1066-2A>G. There were 12 PTS gene variants detected in 36 cases of BH4D, and c.259C>T (p.P87S) (31.9%) was the hotspot mutation.

CONCLUSIONS

The incident of CH has increased from 1999 to 2022 in Zhejiang province, and it is higher than that of national and global levels; while the incidence of HPA is similar to the national average. DUOX2 gene variation is the most common in CH patients; c.728G>A (p.R243Q) is the hotspot mutation in cPKU patients, while c.259C>T (p.P87S) is the hotspot mutation in BH4D patients.

Comorbidity in Congenital Hypothyroidism-A Nationwide, Population-based Cohort Study

CONTEXT

Patients with congenital hypothyroidism (CH) are affected more often than the general population by other chronic diseases and neurological difficulties.

OBJECTIVE

The aim of this nationwide population-based register study was to investigate the incidence of congenital malformations, comorbidities, and the use of prescribed drugs in patients with primary CH.

METHODS

The study cohort and matched controls were identified from national population-based registers in Finland. All diagnoses from birth until the end of 2018 were collected from the Care Register, and subject-specific prescription drug purchases were identified from The Prescription Register from birth until the end of 2017.

RESULTS

Diagnoses of neonatal and chronic diseases were collected for 438 full-term patients and 835 controls (median follow-up time 11.6 years; range, 0-23 years). Newborns with CH were more often found to have neonatal jaundice (11.2% and 2.0%; P < .001), hypoglycemia (8.9% and 2.8%; P < .001), metabolic acidemia (3.2% and 1.1%; P = .007), and respiratory distress (3.9% and 1.3%; P < .003) as compared to their matched controls.Congenital malformations were diagnosed in 66 of 438 (15.1%) CH patients and in 62 of 835 (7.4%) controls (P < .001). The most commonly affected extrathyroidal systems were the circulatory and musculoskeletal systems. The cumulative incidence of hearing loss and specific developmental disorders was higher among CH patients than controls. The use of antidepressant and antipsychotic drugs was similar in CH patients and their controls.

CONCLUSION

CH patients have more neonatal morbidity and congenital malformations than their matched controls. The cumulative incidence of neurological disorders is higher in CH patients. However, our results do not support the existence of severe psychiatric comorbidity.

Congenital hypothyroidism in Northern Ireland: 40 years' experience of national screening programme

OBJECTIVE

The incidence of congenital hypothyroidism (CHT) has progressively increased in several regions around the world but has yet to be evaluated in Northern Ireland (NI). CHT screening programme was introduced in NI in 1980 and has had a relatively unchanged protocol since its inception. The purpose of the study was to evaluate the incidence of CHT in NI from 1981 to 2020 and to explore possible contributing factors to any changes seen over the 40-year period.

DESIGN

This was a retrospective database review of children diagnosed with CHT in NI between 1981 and 2020. Data was collected from the patients' medical (paper and electronic) records, including epidemiological, clinical, laboratory, and radiological features as well as outcomes at 3 years.

RESULTS

Of 800,404 new-borns who were screened for CHT in NI between January 1981 and March 2020, 471 were diagnosed with CHT. There was a steady and significant increase in incidence of CHT over time with an incidence of 26 cases per 100,000 livebirths in 1981 versus 71 cases per 100,000 in 2019 (p < .001). Of these 471, 77 new-borns (16%) were born preterm. The incidence of CHT was observed twice as much in female compared to male new-borns. Diagnostic imaging including radioisotope uptake and thyroid ultrasound scans were performed in 143 cases (30%). Of these, 101 (70%) cases had thyroid dysgenesis and 42 (30%) cases had thyroid dyshormonogenesis. There were 293 (62%) of 471 patients had confirmed permanent CHT, and 90 patients (19%) had transient CHT. Over that period at least 95% of the population were recorded as having United Kingdom/Ireland as country of birth.

CONCLUSION

Our findings demonstrate a nearly tripling of the CHT incidence observed over the last 40 years. This is against a background of a relatively stable population demographics. Future research should focus on the underlying cause(s) of this condition which may include changing environmental exposures in utero.

Congenital hypothyroidism and thyroid function in a Japanese birth cohort: data from The Japan Environment and Children's Study

The most common hormonal and metabolic disease in early childhood is congenital hypothyroidism (CH). This study aimed to describe CH in large-scale birth cohort data and summarize the results of serum thyroid-stimulating hormone (TSH) and free thyroxine (fT4) levels in 2-yr-old children. Data were obtained from the Japan Environment and Children's Study (JECS), and we identified 171 children with CH detected in newborn screenings or medical records (170.5 per 100,000 population). Infants with CH are at higher risk of developing congenital diseases than those without CH. Of 171 children with CH, 20 (11.7%) were diagnosed with congenital heart defects, 33 (19.3%) had chromosomal or other congenital abnormalities, and 23 (13.5%) had Down syndrome. At the age of 2 yr old, the median and 95% reference range values for TSH and fT4 were 2.13 (0.78-5.52) μIU/mL and 1.2 (1.0-1.5) ng/dL, respectively. Moreover, boys had slightly higher TSH and fT4 levels than did girls. Data on the distribution of TSH and fT4 in 2-yr-old children should be useful for decreasing the misclassification of thyroid disorders in the pediatric population. Trial-off treatment and re-evaluation of thyroid function are needed to classify permanent congenital hypothyroidism and transient congenital hypothyroidism after 3 yr of age.

Pathogenic variations in MAML2 and MAMLD1 contribute to congenital hypothyroidism due to dyshormonogenesis by regulating the Notch signalling pathway

BACKGROUND

In several countries, thyroid dyshormonogenesis is more common than thyroid dysgenesis in patients with congenital hypothyroidism (CH). However, known pathogenic genes are limited to those directly involved in hormone biosynthesis. The aetiology and pathogenesis of thyroid dyshormonogenesis remain unknown in many patients.

METHODS

To identify additional candidate pathogenetic genes, we performed next-generation sequencing in 538 patients with CH and then confirmed the functions of the identified genes in vitro using HEK293T and Nthy-ori 3.1 cells, and in vivo using zebrafish and mouse model organisms.

RESULTS

We identified one pathogenic MAML2 variant and two pathogenic MAMLD1 variants that downregulated canonical Notch signalling in three patients with CH. Zebrafish and mice treated with N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butylester, a γ-secretase inhibitor exhibited clinical manifestations of hypothyroidism and thyroid dyshormonogenesis. Through organoid culture of primary mouse thyroid cells and transcriptome sequencing, we demonstrated that Notch signalling within thyroid cells directly affects thyroid hormone biosynthesis rather than follicular formation. Additionally, these three variants blocked the expression of genes associated with thyroid hormone biosynthesis, which was restored by HES1 expression. The MAML2 variant exerted a dominant-negative effect on both the canonical pathway and thyroid hormone biosynthesis. MAMLD1 also regulated hormone biosynthesis through the expression of HES3, the target gene of the non-canonical pathway.

CONCLUSIONS

This study identified three mastermind-like family gene variants in CH and revealed that both canonical and non-canonical Notch signalling affected thyroid hormone biosynthesis.

Epidemiological profile of congenital hypothyroidism at a southern Brazilian state

Objective

To determine the incidence of congenital hypothyroidism (CH) over a 10-year period at the Reference Service in Neonatal Screening of the state of Rio Grande do Sul (RSNS-RS).

Subjects and methods

Historical cohort study including all newborns screened for CH by the RSNS-RS from January 2008 until December 2017. Data of all newborns with neonatal TSH (neoTSH; heel prick test) values ≥ 9 mIU/L were collected. According to neoTSH values, the newborns were allocated into two groups: Group 1 (G1), comprising newborns with neoTSH ≥ 9 mIU/L and serum TSH (sTSH) < 10 mIU/L, and Group 2 (G2), comprising those with neoTSH ≥ 9 mIU/L and sTSH ≥ 10 mIU/L.

Results

Of 1,043,565 newborns screened, 829 (0.08%) had neoTSH values ≥ 9 mIU/L. Of these, 284 (39.3%) had sTSH values < 10 mIU/L and were allocated to the G1 group, while 439 (60.7%) had sTSH ≥ 10 mIU/L and were allocated to the G2 group, and 106 (12.7%) were considered missing data. The overall incidence of CH was 42.1 per 100,000 newborns screened (95% confidence interval [CI] 38.5-45.7/100,000) or 1:2377 screened newborns. The sensibility and specificity of neoTSH ≥ 9 mIU/L were 97% and 11%; of neoTSH 12.6 mUI/L, 73% and 85% respectively.

Conclusion

In this population, the incidence of permanent and transitory CH was 1:2377 screened newborns. The neoTSH cutoff value adopted during the study period showed excellent sensibility, which matters for a screening test.

Predictive factors for the diagnosis of permanent congenital hypothyroidism and its temporal changes in Sergipe, Brazil - A real-life retrospective study

Objective

Congenital hypothyroidism (CH) can be permanent (PCH) or transient (TCH). While the importance of thyroxine in myelination of the brain is undisputed, the benefits to neurodevelopmental outcomes of TCH treatment are controversial. Our objectives were to determine predictive factors for PCH and verify its prevalence changes over time.

Subjects and methods

A total of 165 children were evaluated at 3 years of age to verify the diagnosis of PCH. 130 were submitted to a two-step cluster analysis, with the aim of grouping them into homogeneous clusters. The mean incidence of PCH and TCH was calculated from 2004 to 2010 and 2011 to 2015.

Results

Sixty-six children were diagnosed with PCH, and 99 were diagnosed with TCH. Eighty-one percent of PCH children and all TCH children with thyroid imaging had glands in situ. Eighty children (61.5%) were in Cluster 1, 8 children (6.2%) were in Cluster 2 and 42 children (32.3%) were in Cluster 3. No children had PCH in Cluster 1, while 87.5% of children in Cluster 2 and all children in Cluster 3 had PCH. The most important predictor for PCH was the initial serum TSH, which was marginally higher in importance than the blood spot TSH, followed by the initial serum free T4. The mean incidence of PCH (odds ratio: 1.95, 95% CI 1.36 to 2.95, p < 0.0001) and TCH (odds ratio 1.33, 95%, CI 1.02 to 1.77, p = 0,038) increased over time.

Conclusion

The most important PCH predictors are the initial serum TSH and the blood spot TSH. The mean incidence of both PCH and TCH in our series increased.

Incidence of primary congenital hypothyroidism over 24 years in Finland

BACKGROUND

A rise in the incidence of congenital hypothyroidism (CH) has been reported worldwide. This nationwide study aimed to describe the secular trends and current incidence of CH in Finland.

METHODS

Two independent study cohorts, a national and a regional, were collected from national registers and patient records. The national cohort represents all CH cases born in Finland between 1994 and 2017. Birth data, results of the screening test, and the incidence of CH were reviewed.

RESULTS

Between 1994 and 2017, 1,400,028 children were born in Finland. Of these children, 503 were diagnosed with primary CH (incidence 1:2783). Male-to-female sex ratio was 1:2.0. The nationwide incidence was 33 cases per 100,000 live births between 1994 and 1999, 38 cases per 100,000 live births between 2000 and 2005, 40 cases per 100,000 live births between 2006 and 2011, and 33 cases per 100,000 live births between 2012 and 2017. In the regional cohort (n = 139), the incidence of transient CH was 3.6%. The incidence of mild, moderate, and severe CH remained constant.

CONCLUSIONS

In Finland, the incidence of CH has not changed during the 24-year study period.

IMPACT

As opposed to recent reports worldwide, the incidence of congenital hypothyroidism has not changed between 1994 and 2017 in Finland. The proportions of mild, moderate, and severe congenital hypothyroidism did not change significantly over the study period. Lowering the TSH cut-off limit or increasing immigration did not affect the incidence rate of primary congenital hypothyroidism in Finland.

Guidelines for Newborn Screening of Congenital Hypothyroidism (2021 Revision)

Purpose of developing the guidelines: Newborn screening (NBS) for congenital hypothyroidism (CH) was started in 1979 in Japan, and early diagnosis and treatment improved the intelligence prognosis of CH patients. The incidence of CH was once about one in 5,000-8,000 births, but has been increased with diagnosis of subclinical CH. The disease requires continuous treatment and specialized medical facilities should conduct differential diagnosis and treatment in patients who are positive by NBS to avoid unnecessary treatment. The Guidelines for Mass Screening of Congenital Hypothyroidism (1998 version) were developed by the Mass Screening Committee of the Japanese Society for Pediatric Endocrinology in 1998. Subsequently, the guidelines were revised in 2014. Here, we have added minor revisions to the 2014 version to include the most recent findings. Target disease/conditions: Primary congenital hypothyroidism. Users of the Guidelines: Physician specialists in pediatric endocrinology, pediatric specialists, physicians referring pediatric practitioners, general physicians, laboratory technicians in charge of mass screening, and patients.

Physical Development at School Entry in Children with Congenital Hypothyroidism Diagnosed by the National Program of Newborn Screening in Iran

BACKGROUND

The newborn screening program for diagnosing and treating children with congenital hypothyroidism (CH) in Iran was established in 2004.

OBJECTIVES

This study aimed to evaluate the national program's success in maintaining the physical development and anthropometric indexes of children with CH.

METHODS

This historical cohort study was carried out in five provinces located in five different geographical regions of Iran. The anthropometric indexes, including weight, height, and head circumference of 240 children diagnosed with transient congenital hypothyroidism (TCH) (n = 131) and permanent congenital hypothyroidism (PCH) (n = 109) were measured and compared with those of 240 healthy children aged six.

RESULTS

Mean ± standard deviation (SD) of weight, height, and head circumference of children with CH aged six were 20304.8 ± 4457.9 g, 115.6 ± 5.9 cm, and 50.8 ± 1.7 cm, respectively. Mean ± SD of height (116.7 ± 6.1 cm) and head circumference (51.1 ± 1.7 cm) in the control (healthy) group were significantly higher than those of the CH children group (P < 0.05). Mean ± SD weight in the control group (20741.2 ± 4337.3 g) was higher than that in the CH group (20304.8 ± 4457.9 g). However, the difference was not statistically significant (P = 0.3). No significant difference was observed between TCH and PCH children in the subgroup analysis (P > 0.05).

CONCLUSIONS

Although the mean of anthropometric indexes in CH patients was slightly lower than that in healthy children aged six, the difference between the two groups was insignificant. The physical development of children with CH was evaluated as good. Our results suggested that the newborn screening program for identifying and treating children with CH in Iran may have improved the growth outcomes.

Incidence tendency, etiological classification and outcome of congenital hypothyroidism in Guangzhou, China: an 11-year retrospective population-based study

OBJECTIVES

An increased incidence of congenital hypothyroidism (CH) has been described worldwide over the years. In this study, we aimed to investigate the epidemiologic characteristics of CH, the iodine status in Guangzhou, China and to investigate which factors might influence the CH incidence during the period 2010-2020.

METHODS

We retrospectively reviewed all cases of CH detected by newborn screening during the period 2010-2020. CH was classified as either suspected thyroid dyshormonogenesis (SDH) or thyroid dysgenesis (TD) based on thyroid ultrasound at first diagnosis. Patients were re-evaluated after 4 weeks of L-thyroxine withdrawal at age of 2-3 years to confirm the diagnosis of permanent CH (PCH) or transient CH (TCH).

RESULTS

From 2010 to 2020, 1,655 patients with CH were confirmed from 2,400,383 newborns (1:1,450). The CH incidence increased from 1:2,584 in period [2010-2014] to 1:1,086 in period [2015-2020]. Among the 1,337 patients with thyroid ultrasound, 84.29% were SDH whereas 15.71% had TD. Further analysis revealed that more SDH (78.32%) were TCH whereas more TD (87.12%) turned to be PCH. The proportion of blood spot thyrotropin values >5 mIU/L ranged from 8.03 to 20.46%, indicating iodine deficiency. The prevalence of preterm infants increased from 5.50% in period [2010-2014] to 7.06% in period [2015-2020] (p<0.001).

CONCLUSIONS

In the past decade, the CH incidence has increased progressively. SDH was the majority of CH, most of which were TCH, while most patients with TD were PCH. The increased incidence might be mainly due to iodine deficiency and increased rates of preterm infants in our study.

Ten year analysis of the clinic profile of the tertiary paediatric endocrine service in Western Australia

OBJECTIVES

There is a paucity of information regarding the profile of entire paediatric endocrine clinics and how they are changing. This study aimed to analyse the clinic profile of the Western Australian tertiary paediatric endocrine outpatient service over 10 years and compare to national and international data.

METHODS

Retrospective analysis of the Western Australian Paediatric Endocrine Database (WAPED) between 2007 and 2017 looking at the frequency, proportion and longitudinal change of diagnosis categories, specific diagnoses, and gender breakdown.

RESULTS

In total, 2,791 endocrine diagnoses were recorded for 2,312 patients. The most frequent reason for referral (22.1% of patients), was for evaluation of abnormalities in thyroid function. The most common diagnosis being hypothyroidism (76.7%). Evaluation of short stature was the reason for referral in 19.2% of patients, 14.6% of whom were diagnosed with growth hormone deficiency. Evaluation of puberty disorders, syndromes with endocrine features and disorders of calcium and phosphate metabolism were other common reasons for clinic referral, seen in 11.3, 9.8 and 8.2% of patients respectively. Between 2007 and 2017, the odds ratio of a thyroid diagnosis increased by 1.07 per year (95% CI: 1.02-1.12), whilst the odds ratio of a short stature diagnosis decreased by 0.91 per year (95% CI: 0.87-0.95).

CONCLUSIONS

The profile of the WAPED is similar to previously published national and international data. The analysis of the profile of diagnoses and its longitudinal change over a ten-year period offer a unique opportunity to guide clinic planning, resource allocation and future research.

Clinical features and outcomes of 31 children with congenital hypothyroidism missed by neonatal screening

OBJECTIVE

To investigate the clinical features and outcomes of children with congenital hypothyroidism (CH) missed by neonatal screening.

METHODS

The clinical and laboratory date of 31 children with CH missed by neonatal screening from February 2015 to February 2022 in Guangzhou Women and Children's Medical Center were retrospectively analyzed. Whole-exome high-throughput sequencing analysis was performed in 17 patients.

RESULTS

Among the 31 patients, 19 cases (61.3%) were preterm, 12 cases (38.7%) were term neonates. The median value of gestation age was 36 (26-40) weeks, birth weight was 2.35 (0.75-3.70) kg, diagnosed age was 20 d (7 d-4 years), dry blood spot thyrotropin was 4.18 (0.34-8.97) mU/L. Nine cases (29.0%) were same-sex twins and 4 cases (12.9%) had a family history of hypothyroidism. The initial clinical symptoms were growth retardation in 11 cases (35.5%), prolonged jaundice in 7 cases (22.6%), short stature, abdominal distension, fetal edema and goiter in 1 case (3.2%), respectively. Genetic analysis of the 17 children showed that DUOX2 gene mutations were detected in 10 cases (6 cases with biallelic mutations and 4 cases with monoallelic mutations), of whom 3 had a family history of hypothyroidism. A total of 22 patients were reevaluated at the age of 2-3 years, of whom 17 cases (77.3%) were transient CH and 5 cases (22.7%) were permanent CH. Among the 10 cases with DUOX2 gene mutations, 6 cases were transient CH, 1 case was permanent CH, and 3 cases (< 3 years old) were still under treatment with L-thyroxine.

CONCLUSIONS

False negative results on neonatal screening for CH often occurs in preterm birth, low birth weight, same-sex twins, family history of hypothyroidism, and DUOX2 defects are the common molecular pathogenesis, most of whom are transient CH. Thyroid function should be evaluated in time for children with unexplained slow growth and delayed jaundice regression.

Establishing risk factors and outcomes for congenital hypothyroidism with gland in situ using population-based data linkage methods: study protocol

INTRODUCTION

There has been an increase in the birth prevalence of congenital hypothyroidism (CH) since the introduction of newborn screening, both globally and in the UK. This increase can be accounted for by an increase in CH with gland in situ (CH-GIS). It is not known why CH-GIS is becoming more common, nor how it affects the health, development and learning of children over the long term. Our study will use linked administrative health, education and clinical data to determine risk factors for CH-GIS and describe long-term health and education outcomes for affected children.

METHODS AND ANALYSIS

We will construct a birth cohort study based on linked, administrative data to determine what factors have contributed to the increase in the birth prevalence of CH-GIS in the UK. We will also set up a follow-up study of cases and controls to determine the health and education outcomes of children with and without CH-GIS. We will use logistic/multinomial regression models to establish risk factors for CH-GIS. Changes in the prevalence of risk factors over time will help to explain the increase in birth prevalence of CH-GIS. Multivariable generalised linear models or Cox proportional hazards regression models will be used to assess the association between type of CH and school performance or health outcomes.

ETHICS AND DISSEMINATION

This study has been approved by the London Queen Square Research Ethics Committee and the Health Research Authority's Confidentiality Advisory Group CAG. Approvals are also being sought from each data provider. Obtaining approvals from CAG, data providers and information governance bodies have caused considerable delays to the project. Our methods and findings will be published in peer-reviewed journals and presented at academic conferences.

Non-inferiority of liquid thyroxine in comparison to tablets formulation in the treatment of children with congenital hypothyroidism

OBJECTIVES

The aim of the current prospective randomized control study was to assess efficacy, safety, and non-inferiority of a new liquid L-thyroxine formulation dissolved in glycerol and water (T4^® drops, produced by a Greek pharmaceutical Company, Uni-Pharma, Athens, Greece) in comparison to the standard Tablets form (T4^® tablets, Uni-Pharma, Athens, Greece) in the substitutive treatment of children with congenital hypothyroidism (CH).

METHODS

Thirty-nine children with CH, aged 3-12 years old, were enrolled in the study, after parental Informed Consent has been obtained, while three patients were lost from follow-up. At baseline, all participants had normal thyroid-stimulating hormone (TSH) and Free T4 values. Patients were randomly subdivided according to the assigned treatment in Group A (n=17)-Tablet Form and Group B (n=19)-Liquid Form. TSH and Free T4 levels were evaluated at 0, 2, 4, and 6 months.

RESULTS

TSH values showed a statistically significant difference (p=0.017) between groups only at six months (Group A having higher TSH levels than Group B, albeit within the normal range), while Free T4 levels had no statistical difference throughout the six month study period and were always within the normal range. Moreover, dose adjustments were more frequent in Group A (p=0.038) during the six months. Liquid L-thyroxine substitutive treatment exhibited no statistically significant adverse effects in comparison to the widely used tablets.

CONCLUSIONS

Levothyroxine (LT4) as liquid solution formulation is safe and noninferior to the widely used L-thyroxine Tablets, with less need for dose adjustment, and can therefore be safely used in the treatment of children with CH.

Human and Economic Cost of Disease Burden Due to Congenital Hypothyroidism in India: Too Little, but Not Too Late

BACKGROUND

Congenital hypothyroidism (CH) is one of the most common preventable causes of mental retardation. Implementing newborn screening (NBS) in >52 countries enabled early detection and to initiate treatment of neonates with CH. India is yet to implement a national NBS program even though an estimated 5-15% of sick newborns suffer from genetic and metabolic disorders. Recent pilot studies confirm that the CH incidence rates range from 1 in 500 to 1 in 3,400 live births. Our objective was to estimate overall incidence rates of congenital hypothyroidism and to evaluate the costs and benefits of implementing universal NBS for CH in India.

METHODS

We used the best available epidemiological and cost data to synthesize incidence rates and screening costs for CH in India. We conducted a meta-analysis of country-specific published literature and included 14 studies to calculate baseline CH incidence rates. We used two models to estimate intellectual disability in unscreened cohorts. Disability-adjusted life years (DALY) were calculated to quantify burden of disease utilizing disability weights. Direct costs including screening, confirmatory tests, and treatment costs were obtained from public and private market sources. Economic benefits were calculated from lost DALY using human capital approach and value of statistical life methods, utilizing gross national income (GNI) per capita data and value of statistical life year (VSLY), respectively. Cost discounting was used to estimate the present value of future benefits over lifetime of affected newborns.

RESULTS

The incidence rate of CH in India is 72 (95% CI: 58, 85) cases per 100,000 live births. Based on this data, 1 in 1,388 (95% CI: 1166, 1714) infants were diagnosed with CH in India for the year 2018. The estimated annual incidence ranged from 14,000 to 20,730 cases, and those at risk for intellectual disability ranged from 5,397 to 13,929 cases. Estimated discounted and undiscounted lost DALYs were 57,640 and 410,000, respectively. Direct annual costs for universal screening for CH in India is around USD187 million. Based on current incidence and expected severity of sequelae, economic losses ranged from USD 159 million to 1.1 billion. Benefit-cost ratios ranged from 1.8 to 6.

CONCLUSIONS

Universal NBS for CH is one of the healthcare interventions that is beneficial to prevent morbidity and cost saving. The cumulative economic benefits, derived from prevention of intellectual disability, assuming cost effectiveness threshold of three times of gross domestic product per capita, far outweigh the direct and indirect costs of screening, treatment, and surveillance throughout the life of the affected individuals. Our analysis strongly supports the argument for investing in NBS that provides good value for money and would yield substantial financial gains for the country.

Congenital Hypothyroidism in Preterm Newborns - The Challenges of Diagnostics and Treatment: A Review

Preterm newborns are forced to adapt to harsh extrauterine conditions and endure numerous adversities despite their incomplete growth and maturity. The inadequate thyroid hormones secretion as well as the impaired regulation of hypothalamus-pituitary-thyroid axis may lead to hypothyroxinemia. Two first weeks after birth are pivotal for brain neurons development, synaptogenesis and gliogenesis. The decreased level of thyroxine regardless of cause may lead to delayed mental development. Congenital hypothyroidism (CH) is a disorder highly prevalent in premature neonates and it originates from maternal factors, perinatal and labor complications, genetic abnormalities, thyroid malformations as well as side effects of medications and therapeutic actions. Because of that, the prevention is not fully attainable. CH manifests clinically in a few distinctive forms: primary, permanent or transient, and secondary. Their etiologies and implications bear little resemblance. Therefore, the exact diagnosis and differentiation between the subtypes of CH are crucial in order to plan an effective treatment. Hypothyroxinemia of prematurity indicates dynamic changes in thyroid hormone levels dependent on neonatal postmenstrual age, which directly affects patient's maintenance and wellbeing. The basis of a successful treatment relies on an early and accurate diagnosis. Neonatal screening is a recommended method of detecting CH in preterm newborns. The preferred approach involves testing serum TSH and fT4 concentrations and assessing their levels according to the cut-off values. The possible benefits also include the evaluation of CH subtype. Nevertheless, the reference range of thyroid hormones varies all around the world and impedes the introduction of universal testing recommendations. Unification of the methodology in neonatal screening would be advantageous for prevention and management of CH. Current guidelines recommend levothyroxine treatment of CH in preterm infants only when the diagnose is confirmed. Moreover, they underline the importance of the re-evaluation among preterm born infants due to the frequency of transient forms of hypothyroidism. However, results from multiple clinical trials are mixed and depend on the newborn's gestational age at birth. Some benefits of treatment are seen especially in the preterm infants born <29 weeks' gestation. The discrepancies among trials and guidelines create an urgent need to conduct more large sample size studies that could provide further analyses and consensus. This review summarizes the current state of knowledge on congenital hypothyroidism in preterm infants. We discuss screening and treatment options and demonstrate present challenges and controversies.

Infants Diagnosed with Athyreosis on Scintigraphy May Have a Gland Present on Ultrasound and Have Transient Congenital Hypothyroidism

Scintigraphy using technetium-99m (99mTc) is the gold standard for imaging the thyroid gland in infants with congenital hypothyroidism (CHT) and is the most reliable method of diagnosing an ectopic thyroid gland. One of the limitations of scintigraphy is the possibility that no uptake is detected despite the presence of thyroid tissue, leading to the spurious diagnosis of athyreosis. Thyroid ultrasound is a useful adjunct to detect thyroid tissue in the absence of 99mTc uptake.

AIMS

We aimed to describe the incidence of sonographically detectable in situ thyroid glands in infants scintigraphically diagnosed with athyreosis using 99mTc and to describe the clinical characteristics and natural history in these infants.

METHODS

The newborn screening records of all infants diagnosed with CHT between 2007 and 2016 were reviewed. Those diagnosed with CHT and athyreosis confirmed on scintigraphy were invited to attend a thyroid ultrasound.

RESULTS

Of the 488 infants diagnosed with CHT during the study period, 18/73 (24.6%) infants with absent uptake on scintigraphy had thyroid tissue visualised on ultrasound (3 hypoplastic thyroid glands and 15 eutopic glands). The median serum thyroid-stimulating hormone (TSH) concentration at diagnosis was significantly lower than that in infants with confirmed athyreosis (no gland on ultrasound and no uptake on scintigraphy) (74 vs. 270 mU/L), and median free T4 concentration at diagnosis was higher (11.9 vs. 3.9 pmol/L). Six of 10 (60%) infants with no uptake on scintigraphy but a eutopic gland on ultrasound had transient CHT.

CONCLUSION

Absent uptake on scintigraphy in infants with CHT does not rule out a eutopic gland, especially in infants with less elevated TSH concentrations. Clinically, adding thyroid ultrasound to the diagnostic evaluation of infants who have athyreosis on scintigraphy may avoid committing some infants with presumed athyreosis to lifelong levothyroxine treatment.

Diagnostic re-evaluation and predictors of congenital hypothyroidism with eutopic thyroid gland in Jiangxi, China

OBJECTIVES

An increase in the incidence of congenital hypothyroidism (CH) with eutopic gland has been reported worldwide due to neonatal screening programs. In this study, we aimed to determine the prevalence of transient CH (TCH) and to investigate predictive factors that could distinguish between permanent and transient CH in patients with eutopic thyroid glands.

METHODS

We retrospectively reviewed 508 children treated for CH with eutopic thyroid glands between June 1998 and June 2020 in Jiangxi Newborn Screening Center. All patients were treated with levothyroxine and underwent Diagnostic re-evaluation after 2-3 years of age. Patients were classified as having TCH or permanent CH (PCH) during follow-up.

RESULTS

Of the 508 patients initially treated for CH with a normally located gland, 335 patients (65.9%) were classified in the TCH group and 173 (34.1%) in the PCH group based on the defined criteria. Multivariate analysis revealed that TCH was associated with a lower levothyroxine dose at 24 months of age (p<0.001) and a lower likelihood of having a first-degree family history of CH (p=0.026) than PCH. Gender, prematurity, low birth weight, initial CH severity such as serum TSH and FT4 levels, or bone maturation delay at diagnosis had no effect. Receiver operating characteristics curve analysis showed that a cutoff of 2.3 μg/kg/day for levothyroxine dose requirement at 24 months of age had a sensitivity of 71% and a specificity of 70% for predicting transient CH, with values below this threshold considered predictive of transient CH.

CONCLUSIONS

TCH presents a significant portion of patients with CH. The levothyroxine dose requirement at 24 months of age has a predictive role in differentiating TCH from PCH in CH patients with eutopic thyroid glands.

Assessment of thyroid function in the preterm and/or very low birth weight newborn

The screening program or early detection of congenital hypothyroidism is one of the greatest advances achieved in Pediatrics. Thyroid hormones are essential for brain development and maturation, which continue into the neonatal stage. Alterations in thyroid function in premature and underweight children in the first months of life causes irreversible damage to the central nervous system and is one of the most frequent and avoidable causes of mental retardation. Diagnosis in the neonatal period is difficult, so it requires an analytical study to be able to carry out the appropriate treatment. The relevance of this problem justifies its communication to all areas of pediatrics. The main objective is to avoid brain damage in these patients. Other aspects to optimize the adequate development of these children with all the necessary periodic controls and to achieve the inclusion of the diagnosis of thyroid alterations during the stay in neonatal units and in the first months of life, need to implement the resources of the health centers and continue advancing according to current knowledge. In this document, we will focus on the screening of preterm newborns VLBW (<32 weeks of gestation) and/or very low weight for gestational age (1500-1000 g VLBW or <1000 g) and the function evaluation protocol thyroid in premature babies. We update the diagnostic procedures, the essential and complementary tests required, the etiology and the differential diagnoses in this pathology.

Geographic variations in the incidence of congenital hypothyroidism in China: a retrospective study based on 92 million newborns screened in 2013-2018

Background:

Although congenital hypothyroidism (CH) has been widely studied in Western countries, CH incidence at different administrative levels in China during the past decade remains unknown. This study aimed to update the incidence and revealed the spatial pattern of CH incidence in the mainland of China, which could be helpful in the planning and implementation of preventative measures.

Methods:

The data used in our study were derived from 245 newborns screening centers that cover 30 provinces of the Chinese Newborn Screening Information System. Spatial auto-correlation was analyzed by Global Moran I and Getis-Ord Gi statistics at the provincial level. Kriging interpolation methods were applied to estimate a further detailed spatial distribution of CH incidence at city level throughout the mainland of China, and Kulldorff space scanning statistical methods were used to identify the spatial clusters of CH cases at the city level.

Results:

A total of 91,921,334 neonates were screened from 2013 to 2018 and 42,861 cases of primary CH were identified, yielding an incidence of 4.66 per 10,000 newborns screened (95% confidence interval [CI]: 4.62–4.71). Neonates in central (risk ratio [RR] = 0.84, 95% CI: 0.82–0.85) and western districts (RR = 0.71, 95% CI: 0.69–0.73) had lower probability of CH cases compared with the eastern region. The CH incidence indicated a moderate positive global spatial autocorrelation (Global Moran I value = 0.394, P < 0.05), and the CH cases were significantly clustered in spatial distribution. A most likely city-cluster (log-likelihood ratio [LLR] = 588.82, RR = 2.36, P < 0.01) and 25 secondary city-clusters of high incidence were scanned. The incidence of each province and each city in the mainland of China was estimated by kriging interpolation, revealing the most affected province and city to be Zhejiang Province and Hangzhou city, respectively.

Conclusion:

This study offers an insight into the space clustering of CH incidence at provincial and city scales. Future work on environmental factors need to focus on the effects of CH occurrence.

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.

Congenital Hypothyroidism: Space-Time Clustering of Thyroid Dysgenesis Indicates a Role for Environmental Factors in Disease Etiology

Background: The etiology of most cases of congenital hypothyroidism (CHT) due to thyroid dysgenesis (DG) is unknown. If transient environmental factors can impact on thyroid gland development, then clustering of cases in time and/or space may occur, and this would be more likely in thyroid DG than dyshormonogenesis (DHG). Methods: The newborn screening program for CHT in Scotland is linked to a central database that includes case details such as postcode. The etiology of CHT is investigated in many cases of CHT using scintigraphy and/or ultrasonography. We looked for evidence of a change in CHT incidence with year of birth and according to season of the year. We then undertook space-time clustering analysis (using a method based on K-functions, with nearest neighbor thresholds) of CHT in Scotland between 1979 and 2015. We also looked for evidence of overall changes associated with sex and area-based birth density. Results: Of 531 cases with CHT during the study period, 290 cases had been categorized as DG (n = 229) or DHG (n = 61) following more detailed investigation. The incidence of CHT increased with year of birth and was in part linked to changing methodology, but there was no seasonality. There was no evidence of overall space-time clustering (p = 0.06), but there was evidence of clustering in babies with DG (p = 0.007). This picture appeared to be most closely linked to underlying thyroid gland hypoplasia rather than thyroid gland agenesis or ectopia. There was significant space-time clustering for both males and females, but clustering was restricted to lesser birth density areas. There was also evidence of clustering for unknown cases (p < 0.001). Clustering of these cases was restricted to females but was present for cases from both greater and lesser birth density areas. There was no evidence of clustering in cases of DHG. Conclusions: These data suggest that an unidentified environmental factor or factors may be involved in the etiology of thyroid DG in Scotland. The variation in CHT incidence observed internationally may reflect environmental as well as genetic factors.

Re-Evaluation of the Prevalence of Permanent Congenital Hypothyroidism in Niigata, Japan: A Retrospective Study

Although newborn screening (NBS) for congenital hypothyroidism (CH) in Japan started more than 40 years ago, the prevalence of CH remains unclear. Prevalence estimations among NBS-positive CH individuals include those with transient hypothyroidism and transient hyperthyrotropinemia, and re-evaluation with increasing age is necessary to clarify the actual incidence. Thus, we re-evaluated the incidence of permanent CH. Of the 106,114 patients who underwent NBS in the Niigata Prefecture, Japan, between April 2002 and March 2006, 116 were examined further due to high thyroid-stimulating hormone levels (>8 mIU/L) and were included in the study. We retrospectively evaluated their levothyroxine sodium (LT4) replacement therapy status from the first visit to 15 years of age. Of the 116 NBS-positive patients, 105 (91%) were initially examined in our department. Of these, 72 (69%) started LT4 replacement therapy on the first visit. Subsequently, 27 patients continued LT4 replacement until 15 years of age after multiple re-evaluations. The prevalence of permanent CH in the Niigata Prefecture during this period was 1 in 2500-3500 children. Ultimately, 62.5% of patients on LT4 replacement discontinued treatment by 15 years of age. This is the first study to clarify the true prevalence of permanent CH in Japan.

[Assessment of thyroid function in the preterm and/or very low birth weight newborn]

The screening program or early detection of congenital hypothyroidism is one of the greatest advances achieved in Pediatrics. Thyroid hormones are essential for brain development and maturation, which continue into the neonatal stage. Alterations in thyroid function in premature and underweight children in the first months of life causes irreversible damage to the central nervous system and is one of the most frequent and avoidable causes of mental retardation. Diagnosis in the neonatal period is difficult, so it requires an analytical study to be able to carry out the appropriate treatment. The relevance of this problem justifies its communication to all areas of pediatrics. The main objective is to avoid brain damage in these patients. Other aspects to optimize the adequate development of these children with all the necessary periodic controls and to achieve the inclusion of the diagnosis of thyroid alterations during the stay in neonatal units and in the first months of life, need to implement the resources of the health centers and continue advancing according to current knowledge. In this document, we will focus on the screening of preterm newborns VLBW (<32 weeks of gestation) and/or very low weight for gestational age (1500-1000g VLBW or <1000g) and the function evaluation protocol thyroid in premature babies. We update the diagnostic procedures, the essential and complementary tests required, the etiology and the differential diagnoses in this pathology.

[Risk factors for neonatal congenital hypothyroidism: a Meta analysis]

OBJECTIVE

To investigate the risk factors for congenital hypothyroidism (CH) in neonates, and to provide a reference for the prevention of CH.

METHODS

The databases including China Biomedical Literature Service System, China National Knowledge Infrastructure, Wanfang Data, and Weipu Periodical Database, PubMed, Web of Science, Embase, SpringerLink, and Elsevier/ScienceDirect were searched for studies on the risk factors for CH in neonates published up to August 1, 2020. R 3.6.2 and RevMan 5.3 software were used to perform a Meta analysis.

RESULTS

A total of 20 studies were included, with 13 case-control studies and 7 cross-sectional studies. There were 11 564 neonates in total, with 3 579 neonates in the case group and 7 985 neonates in the control group. The Meta analysis showed that advanced maternal age (OR=2.111, 95%CI: 1.275-3.493), thyroid disease during pregnancy (OR=3.365, 95%CI: 1.743-6.500), gestational diabetes mellitus (OR=2.158, 95%CI: 1.545-3.015), anxiety (OR=3.375, 95%CI: 2.133-5.340), medication during pregnancy (OR=2.774, 95%CI: 1.344-5.725), radiation exposure during pregnancy (OR=3.262, 95%CI: 1.950-5.455), family history of thyroid disease (OR=8.706, 95%CI: 5.991-12.653), low birth weight (OR=2.674, 95%CI: 1.895-3.772), fetal macrosomia (OR=1.657, 95%CI: 1.187-2.315), preterm birth (OR=2.567, 95%CI: 2.070-3.183), post-term birth (OR=2.083, 95%CI: 1.404-3.091), twin pregnancy or multiple birth (OR=3.455, 95%CI: 1.958-6.096), and birth defects (OR=6.038, 95%CI: 3.827-9.525) were risk factors for CH in neonates.

CONCLUSIONS

Advanced maternal age, gestational thyroid disease, gestational diabetes mellitus, anxiety, medication during pregnancy, radiation exposure during pregnancy, family history of thyroid disease, low birth weight, fetal macrosomia, preterm birth, post-term birth, twin pregnancy or multiple pregnancy, and birth defects may increase the risk of CH in neonates.

Transition readiness among adolescents with rare endocrine conditions

OBJECTIVE

Adolescents and young adults (AYA) with common endocrine disorders show a high dropout (up to 50%) after the transfer from paediatric to adult endocrinology. Little is known about transition readiness in rare endocrine conditions (rEC). This study aims to assess medical self-management skills (SMS) among AYA with rEC in relation to age and gender, in order to understand dropout and increase transition readiness.

DESIGN

Cross-sectional study using web-based medical self-management questionnaires.

METHODS

Questionnaires consisting of 54 questions in seven domains were filled out by the adolescents before the first shared appointment with both paediatric and adult endocrinologist.

RESULTS

Fifty-seven patients (median age 17 years, 25/57 females) participated and generally scored well on most items. However, one out of seven did not know the name of their disorder, one sixth of the glucocorticoid users did not know that dose should be adapted in case of illness or surgery, over one-fifth had never ordered their repeat prescriptions themselves and two-thirds had never had a conversation alone with their doctor.

CONCLUSIONS

Several SMS among patients with rEC are insufficient, with regard to medical knowledge, practical skills and communication. As SMS are only weakly related to non-modifiable factors, such as age and gender, we recommend focussing on other factors to increase transition readiness. The timing, amount and 'mode' of medical information should be individualised. Transition checklists should be used to detect shortcomings in practical skills and communication, which can subsequently be trained with the help of parents, caregivers and/or e-technology.

Combined use of thyroid stimulating hormone plus free thyroxine levels and gestational age at birth for the prediction of neonatal hypothyroidism and associated risk factors

The present study aimed to explore the effectiveness of the combined use of thyroid-stimulating hormone (TSH) and free thyroxine [(FT4); TSH+FT4] levels and gestational age at birth to predict neonatal hypothyroidism and to identify the risk factors associated with the disease. The clinical data of 686 neonates with suspected hypothyroidism (TSH >10 mIU/l) who were admitted to The First Affiliated Hospital of Chongqing Medical University were retrospectively analyzed. From these, 70 neonates with confirmed hypothyroidism were assigned to the patient group and another 70 neonates with normal thyroid function to the normal (control) group. Sex, gestational age at birth, Apgar score, birth weight, body length, head circumference and heart rate data were collected. TSH and FT4 levels were measured by electrochemiluminescence immunoassay, and the predictive value of combined use of TSH+FT4 and gestational age at birth on neonatal hypothyroidism was analyzed. The prespecified secondary outcomes were the risk factors for neonatal hypothyroidism determined using univariate and logistic regression analyses. TSH levels were significantly higher, whereas FT4 levels were lower in the patient group at 3 days of age compared with the control group (P<0.05). After 8-week treatment with thyroxine, these levels were not significantly different between the patient and control groups (P<0.05). The combined use of TSH+FT4 levels and gestational age at birth to predict neonatal hypothyroidism demonstrated a significantly improved sensitivity, specificity, accuracy, positive predictive value and negative predictive value (92.86, 97.26, 96.76, 81.25 and 99.07%, respectively) compared with the use of only TSH+FT4 levels (P<0.05). Logistic regression analysis revealed a low gestational age at birth, maternal thyroid dysfunction and low birth weight were risk factors for neonatal hypothyroidism (P<0.05). The combined use of TSH+FT4 levels and gestational age at birth resulted in an improved prediction of neonatal hypothyroidism and contributed to early therapeutic intervention. Thus, special intervention is necessary for pregnant women with thyroid dysfunction to reduce the incidence of neonatal hypothyroidism.

Thyroid Receptor Antagonism of Chemicals Extracted from Personal Silicone Wristbands within a Papillary Thyroid Cancer Pilot Study

Research suggests that thyroid cancer incidence rates are increasing, and environmental exposures have been postulated to be playing a role. To explore this possibility, we conducted a pilot study to investigate the thyroid disrupting bioactivity of chemical mixtures isolated from personal silicone wristband samplers within a thyroid cancer cohort. Specifically, we evaluated TRβ antagonism of chemical mixtures extracted from wristbands (n = 72) worn by adults in central North Carolina participating in a case-control study on papillary thyroid cancer. Sections of wristbands were solvent-extracted and analyzed via mass spectrometry to quantify a suite of semivolatile chemicals. A second extract from each wristband was used in a bioassay to quantify TRβ antagonism in human embryonic kidney cells (HEK293/17) at concentrations ranging from 0.1 to 10% of the original extract (by volume). Approximately 70% of the sample extracts tested at a 1% extract concentration exhibited significant TRβ antagonism, with a mean of 30% and a range of 0-100%. Inhibited cell viability was noted in >20% of samples that were tested at 5 and 10% concentrations. Antagonism was positively associated with wristband concentrations of several phthalates, organophosphate esters, and brominated flame retardants. These results suggest that personal passive samplers may be useful in evaluating the bioactivities of mixtures that people contact on a daily basis. We also report tentative associations between thyroid receptor antagonism, chemical concentrations, and papillary thyroid cancer case status. Future research utilizing larger sample sizes, prospective data collection, and measurement of serum thyroid hormone levels (which were not possible in this study) should be utilized to more comprehensively evaluate these associations.

Multiorgan involvement and management in children with Down syndrome

AIM

To review multiorgan involvement and management in children with Down syndrome (DS).

METHODS

A literature review of articles from 1980 to 2019 using the MEDLINE interface of PubMed was performed using the following search terms- [Down syndrome] or [Trisomy 21] AND [Cardiology] or [Respiratory] or [neurodevelopment] or [epilepsy] or [musculoskeletal] or [immune system] or [haematological] or [endocrine] or [gastrointestinal] or [ophthalmological] or [Ear Nose Throat] or [dermatology] or [renal].

RESULTS

Congenital heart disease particularly septal defects occur in over 60% of infants with DS and 5%-34% of infants develop persistent pulmonary hypertension of the newborn irrespective of a diagnosis of congenital heart disease. Early recognition and management of aspiration, obstructive sleep apnoea and recurrent lower respiratory tract infections (LRTI) could reduce risk of developing pulmonary hypertension in later childhood. Children with DS have an increased risk of autistic spectrum disorder, attention deficit disorder and epilepsy particularly infantile spasms, which are associated with poor neurodevelopmental outcomes. Congenital anomalies of the gastrointestinal and renal system as well as autoimmune diseases, coeliac disease, arthropathy, thyroid dysfunction fold diabetes mellitus and dermatological conditions are more common. Hearing and visual anomalies are also well recognised association with DS (Table 1).

CONCLUSION

Children with DS are at an increased risk of multiorgan comorbidities. Organ-specific health surveillance may provide holistic care for the children and families with DS throughout childhood.

Determining Reference Ranges for Total T4 in Dried Blood Samples for Newborn Screening

The purpose of this study was to define reference intervals for total thyroxine (tT4) in dried blood samples (DBSs) obtained for newborn screening. The aim of our study was to assess the possible benefit of measuring tT4 concentrations directly in DBSs obtained for newborn screening in premature and term-born infants. In order to have a sufficient number of samples for the extremely premature infants (<30 weeks), we set up a retrospective study, measuring the concentrations in DBSs collected over the previous 21 weeks. This time frame was a result of the included miniature study of tT4 stability in DBSs. We found that tT4 strongly correlated with gestational age (GA) in premature infants, highlighting the need for age-specific reference ranges. For term-born infants, the tT4 ranges did not vary significantly among different gestational ages, allowing for the use of one single reference range.

Same-sex twins have a high incidence of congenital hypothyroidism and a high probability to be missed at newborn screening

BACKGROUND

We estimated the incidence of CH in twins, analyse the clinical features of CH cases in twins and further evaluate the CH screening strategy and recall procedures for twins.

METHODS

A retrospective investigation of the screening results and confirmed cases in 724,791 newborns was conducted from 2015 to 2017 in Guangzhou. Clinical features were compared between twins with CH and singletons with CH. In addition, the twins were further divided into same-sex twins and different-sex twins to analyse the characteristics and incidence of CH and to compare differences in the confirmed cases in the 2 groups.

RESULTS

The incidence of CH in same-sex twins was 1/593, which was much higher than the incidence of CH in singletons (1/1323) and different-sex twins (1/3060). Of the 20 twins diagnosed with CH, 17 were same-sex twins and 3 were different-sex twins. Among the six pairs of same-sex twins with CH, four had TSH inconsistency, which reached 67%. Eight of the 17 cases of same-sex twins diagnosed with CH had negative results at the first screening.

CONCLUSIONS

Distinguishing same-sex twins from different-sex twins during newborn screening is more feasible. The incidence of CH in same-sex twins is much higher than that in the general population and the risk of transient CH is relatively high. In positive cases in same-sex twins, the simultaneous recall of the twin can effectively avoid a missed diagnosis. The screening center should properly evaluate the recall strategy and screening procedure for twins, especially twins of the same-sex.

Congenital Hypothyroidism: 8-Year Experience Using 2 Newborn Screens in Alabama

BACKGROUND/AIMS

Newborn screening protocols for congenital hypothyroidism (CH) vary as to whether a TSH or T4 algorithm or some combination is performed. We aimed to determine the 3-year clinical outcome of infants diagnosed with CH and screen-positive for CH using a 2-screen protocol that measures both T4 and TSH on all specimens.

METHODS

Retrospective analysis of patients with CH who were detected by first (NBS1) or second (NBS2) newborn screen in Alabama (2009-2016) and followed at our university-based practice. Clinical follow-up established the final diagnoses in 146 patients, including a subset of 72 patients with eutopic glands.

RESULTS

168 patients were studied: 139 (83%) were detected by NBS1 and 29 (17%) by NBS2. Screening T4 concentrations were 45% reduced in NBS2 compared to NBS1 (p= 0.0002). Thyroid dysgenesis was present in 55% of NBS1 patients while all in NBS2 were eutopic. Follow-up of 146 patients confirmed permanent CH in 92 patients in NBS1 (75%) and 5 in NBS2 (20%). Hispanic infants were only detected by NBS1, and 93% had permanent CH. Transient CH was associated with congenital heart disease. In patients with eutopic, permanent CH, dyshormonogenesis was confirmed in 23% of NBS1 patients and 40% of NBS2. One case of central CH was detected by each screen.

CONCLUSIONS

This 8-year, retrospective study buttresses the importance of a 2-screen approach for CH by identifying 5 infants with clinically significant permanent thyroid dysfunction including dyshormonogenesis and central hypothyroidism. It is the first 2-screen study to incorporate thyroid ultrasound. Disconcertingly, 4 of 5 second-screen infants with permanent CH had no risk factors for CH, and these infants would otherwise not have been detected.

Thyroid-Stimulating Hormone Reference Ranges for Preterm Infants

BACKGROUND AND OBJECTIVES

Many newborn screening (NBS) programs now perform repeat or serial NBS to detect congenital hypothyroidism. There is wide variation in thyroid-stimulating hormone (TSH) cutoffs used by NBS programs. Data on TSH reference ranges in preterm infants at increasing postnatal age are limited. Our study objective was to determine TSH reference ranges for preterm infants born at <32 weeks' gestation.

METHODS

We analyzed serial TSH levels on NBS performed on infants born between 22 and 31 weeks' gestation from 2012 to 2016 in Wisconsin. The study cohort was divided into 2 groups (22-27 and 28-31 weeks), and TSH percentiles were defined from birth to the term equivalent gestational age.

RESULTS

The study cohort consisted of 1022 and 2115 infants born at 22 to 27 and 28 to 31 weeks' gestation, respectively. The 95th percentile TSH level for the group born at 22 to 27 weeks' gestation gradually decreased and reached a nadir at ∼10 to 11 weeks. In contrast, for the group born at 28 to 31 weeks' gestation, the 95th percentile TSH level reached a nadir at ∼5 to 6 weeks. At 3 to 4 weeks after birth, the 95th percentile TSH level ranged from 11 to 11.8 μIU/mL for the group born at 22 to 27 weeks' gestation and ranged from 8.2 to 9 μIU/mL for the group born at 28 to 31 weeks' gestation.

CONCLUSIONS

Using a statewide cohort of preterm infants, we constructed TSH reference charts from birth to the term equivalent gestation for preterm infants born at <32 weeks' gestation. Use of a single cutoff for all preterm infants might lead to misdiagnosis. The differences in TSH levels according to gestational-age categories might explain the increased frequency in congenital hypothyroidism diagnoses among preterm infants. These data are useful for defining age-adjusted NBS TSH cutoffs for preterm infants.