Congenital hypothyroidism in neonates

Newborn screening for congenital hypothyroidism, congenital adrenal hyperplasia and glucose-6-phosphate dehydrogenase deficiency in Bihar: A pressing priority in today's time

Background and Objective

Newborn screening (NBS) aims towards early detection of congenital disorders or prevention of intellectual and physical defects and life-threatening illness. Three disorders namely congenital hypothyroidism (CH), congenital adrenal hyperplasia (CAH) and glucose-6-phosphate dehydrogenase deficiency (G-6-PDD) were selected for a preliminary study for NBS. The study aimed to establish NBS in the Indian scenario that could lay a framework for future such initiatives.

Methods

A screening programme was conducted at a tertiary care hospital for 1 year. All the neonates born at All India Institute of Medical Sciences (AIIMS), Patna, were screened for their blood levels of glucose-6-phosphate dehydrogenase (G-6-PD), 17-hydroxyprogesterone (17-OHP) and thyroid-stimulating hormone (TSH). Heel-prick blood samples were collected within 48-72 h of birth, and the level of these parameters was accessed by enzyme immunoassay (EIA).

Results

A total of 492 neonates were born from January 2020 to December 2020, of which 369 newborns were screened for CAH, CH and G-6-PDD. Of 369 neonates, one case (male) had an increased level of TSH, six cases (all males) had an increased level of 17-OHP and no case was found with G-6-PDD.

Interpretation and Conclusions

Preliminary data on the prevalence of various genetic disorders revealed that CAH is the most prevalent disorder followed by CH in the population of Bihar. More efforts need to be undertaken to create awareness and to make screening a successful programme in India. A cost-effective nationwide screening programme is highly recommended for the detection of such cases at the earliest to avoid their future complication.

Higher frequency of Congenital Hypothyroidism among Newborns, District Dera Ghazi Khan-Punjab, Pakistan: A case control study

OBJECTIVES

The study objective was to establish serum TSH cut off value for diagnosis of new case of congenital hypothyroidism and to estimate frequency of Congenital Neonatal Hypothyroidism.

METHODS

A case control study was conducted at DHQ Teaching Hospital of DG Khan Medical College, Dera Ghazi Khan during 2020 to establish reference values of TSH and T4 for study population. Sample size was calculated by classical sample size calculation formula Cochran WG 1977 sampling technique. A group of 30 neonates of normal, healthy, euthyroid mothers was taken as Neonatal Control Group to estimate levels of TSH and total T4 in normal neonates. Neonatal Study Group was neonates of hypothyroid mothers (n=75). Simple random sampling technique was applied.

RESULTS

Mean (mean ± SD) Serum TSH levels of Neonatal Control Group were found to be 3.58 ± 03.09 mIU/l. Mean Serum TSH levels among Neonatal Study Group were found to be 6.88 ±12.95 mIU/l and serum total T4 were found to be 16.78 ± 6.96ug/dl on 3-7 days of life. Serum total T4 (mean ± SD) levels of Neonatal Control Group were 9.73 ± 03.39 ug/dl. Neonatal serum TSH more than 15mIU/l was taken as cut off value to diagnose a case of CNH. So, frequency of CNH was 8% among neonates of study group.

CONCLUSIONS

The TSH cut off value of >15mIU/l was established for case detection of CNH. Our findings of CNH in district Dera Ghazi Khan (8%) are the highest frequency of CNH reported so far in Pakistan.

Trends of congenital hypothyroidism and inborn errors of metabolism in Pakistan

BACKGROUND

Metabolic disorders are heterogeneous group of genetic disorders that are responsible for significant neonatal and infant morbidity and mortality worldwide. In developing countries like Pakistan where infant mortality is high current population based studies are unable to gauge contribution of metabolic disorders in causing mortality and morbidity. It is essential to address this gap by a review of available scattered Pakistani data related to metabolic disorders specifically congenital hypothyroidism and inborn error of metabolism to calculate probable burden of these disorders.

MAIN BODY

Unfortunately currently in Pakistan newborn screening which identifies these illnesses at birth as a preventive strategy are not available. For current review data was collected through a systematic search of published articles (including data related to screening in certain subgroups of patients admitted to pediatric/neonatal intensive care units, patients with developmental delay/mental retardation).

CONCLUSION

The primary aim of this review was to get an estimate of the disease burden in the Pakistani population as true prevalence of Congenital Hypothyroidism and Inborn Errors of Metabolism in Pakistan is not available. This systematic review will help us to identify the rough idea about the scale of problem in Pakistan.

Performance in motor, communicative and cognitive skills of girls with congenital hypothyroidism treated from the neonatal period

OBJECTIVE

To compare the performance in gross motor, fine motor-adaptive, language, cognitive and personal-social development skills of girls with a mean age of 36 to 71 months with Congenital Hypothyroidism treated from the neonatal period with that of their peers without thyroid alterations.

METHODS

The participants included in the study were 30 children aged between 36 and 70 months divided into two groups paired for chronological age and socioeconomic status: 15 girls diagnosed with Congenital Hypothyroidism - Experimental Group (EG) and 15 girls without thyroid changes - Control Group (CG). The following assessment instruments were used: Interview with parents, Peabody Picture Vocabulary Test - Revised (PPVT-R), and Denver Developmental Screening Test - 2nd edition (DDST-II). Psychological testing of intellectual functioning was conducted with application of the Stanford-Binet Intelligence Scale (SBIS). The descriptive statistical analysis was performed using Student's t-test and the Mann-Whitney test at a significance level of 5% (p<0.05).

RESULTS

Comparison of the PPVT-R and SBIS results showed a statistically significant difference between the EG and CG. Comparison of the DDST-II results showed a statistically significant difference between the groups for the fine motor-adaptive, language and gross motor areas.

CONCLUSION

The present study confirms that Congenital Hypothyroidism affects child development, even when children are diagnosed and treated early, leading to alterations that can impair their motor, cognitive and language development.

Trend of Congenital Hypothyroidism Incidence and Its Affecting Factors in Shahr-e-Kord, Western Iran

BACKGROUND

Congenital hypothyroidism is one of the most common endocrine disrupters and metabolism, and is one of the most important preventable causes of physical and mental disabilities.

METHODS

This was a case-control study, in which 54468 infants were screened from 2006 to 2014 in Shahre-Kord, western Iran. To describe the data, central and dispersion indices such as mean and standard deviation was used. For modeling, logistic regression was used. All the tests were performed at the significant level of 5%.

RESULTS

Overall, 111 cases were diagnosed with hypothyroidism, which made the prevalence value equal to 2 cases per 1000 births. The prevalence in females and males was 1.9 and 2.2 per 1,000 birth, respectively. The odds ratio for this disorder was 4.47(2.42-9.28) for the neonates with a family history of hypothyroidism and 1.72(1.05-2.82) for those born through cesarean.

CONCLUSION

The incidence of this disorder is similar in males and females, and the incidence of this disease in people with a family history is far more than others.

Incidence of Congenital Hypothyroidism in Western Rajasthan Using Cord Blood Thyroid-stimulating Hormone Levels as a Screening Tool: A Cross-sectional Hospital-based Study

BACKGROUND

Congenital hypothyroidism (CH) is considered the most common preventable cause of intellectual impairment, with a worldwide annual incidence of 1:4000 live births. In the absence of screening program actual incidence in India is not exactly known, but in previous studies it varies from 1:500 to 1:3400. We wished to find out the incidence of CH in Western Rajasthan using cord blood TSH as a screening tool and venous TSH within 14 days of life as a confirmatory test.

METHODS

This cross sectional descriptive study was conducted over a period of six months in teaching hospitals attached to Medical College. Cord blood TSH value of 20 mIU/L or >20 mIU/L was taken as cut off for screening and all screen positive neonates were re-tested for serum TSH by taking venous samples within 14 days of life. Repeat TSH levels of 20mIU/L or more tested by Enzyme Linked Fluorescent Assay were considered confirmatory.

RESULTS

Total 9558 cord blood samples were analyzed for TSH levels, out of which 533 came out to be screen positive (recall rate 5.57%). Out of these 58 could not be confirmed, so were excluded from the further analysis. Effective sample size and screen positive cases dropped to 9500 and 475 respectively, and out of these 13 were confirmed as CH (incidence - 1.37 per thousand live births).

CONCLUSIONS

Considering the previous studies, incidence of CH is much higher in Western Rajasthan than the anticipated. Overall in India CH seems to be more prevalent than the other parts of the world, necessitating the need of national screening program.

Compound Heterozygous Mutations in the DUOX2/DUOXA2 Genes Cause Congenital Hypothyroidism

The mutations in the dual oxidase 2 (DUOX2) and dual oxidase maturation factor 2 (DUOXA2) genes can cause congenital hypothyroidism (CH). This study reports the pedigree with goitrous congenital hypothyroidism (GCH) due to the coexistence of heterozygous mutations in the DUOX2 and DUOXA2 genes. The two sisters with GCH were diagnosed with CH at neonatal screening and were enrolled in this study. The DUOX2, DUOXA2, and thyroid peroxidase (TPO) genes were considered for genetic defects screening. Family members of the patients and normal controls were also enrolled and evaluated. The two girls harbored compound heterozygous mutations, including a new mutation of c.2654G>T (p.R885L) in the maternal DUOX2 allele and c.738C>G (p.Y246X) in the paternal DUOXA2 allele, that has been previously reported. The germline mutations from the families were consistent with an autosomal recessive inheritance pattern. No mutations in the TPO gene and the controls were observed.

Next-generation sequencing of NKX2.1, FOXE1, PAX8, NKX2.5, and TSHR in 100 Chinese patients with congenital hypothyroidism and athyreosis

BACKGROUND

The abnormal expression of certain transcription factors (NKX2.1, FOXE1, NKX2.5, and PAX8) and thyroid stimulating hormone receptor (TSHR) genes has been associated with athyreosis, which is a form of thyroid dysgenesis (TD). We aimed to identify candidate gene mutations in CH patients with athyreosis and to establish the genotype-phenotype correlations in a Chinese population.

METHODS

The exons and flanking sequences of NKX2.1, FOXE1, NKX2.5, PAX8, and TSHR were screened by next-generation sequencing and further confirmed by direct Sanger sequencing. The mutation frequencies were calculated and compared against databases. The relationship between genotype and phenotype was also determined.

RESULTS

Seven variants were detected in TSHR-p.P52T, p.G132R, p.M164K, p.R450H, p.C700E, p.A522V, and p.R528S. The p. G132R, p. M164K and p. R528S variants were first identified in public databases. Five variants (p.G44D, p.G360V, p.R401Q, p.L418I, and p.E453Q) were found in NKX2.1 and one variant (p.P243T) was detected in FOXE1. In addition, one variant (p.N291I) was found in NKX2.5 and two variants (p.A355V and c.-26G>A) were detected in PAX8.

CONCLUSIONS

Our study indicated that TSHR mutations have phenotypic variability and has further expanded the mutation spectrum of TSHR. We also revealed that the rate of NKX2.1, FOXE1, NKX2.5, and PAX8 mutations were low in patients with CH and athyreosis, in contrast to the higher rate of TSHR mutations.

Two novel TSHR gene mutations (p.R528C and c.392+4del4) associated with congenital hypothyroidism

Inactivating mutations of the thyrotropin receptor (TSHR) gene are responsible for non-goitrogenic congenital hypothyroidism (CHNG). This study aimed to investigate mutations in the TSHR gene in 20 children with CHNG. Genomic DNA was extracted from peripheral blood leukocytes and was used for mutation screening by direct sequencing. Analyses of the TSHR gene revealed two novel variants in a 2-year-old boy with thyroid hypoplasia: a missense mutation c.1582C>T (p.R528C) and a splice-site deletion c.392+4del4. Bioinformatics analysis demonstrated that both variants are capable of causing disease. Family members of the patient with two mutations and normal controls were also recruited and investigated. Germline mutations from the proband's family were consistent with an autosomal recessive inheritance pattern. These findings indicate that two novel inactivating mutations (p.R528C and c.392+4del4) in the TSHR gene can cause CHNG.

Total knee arthroplasty in patients with skeletal dysplasia

INTRODUCTION

Dwarfism is a challenge in arthroplasty. The anatomical features provide a lot of pitfalls. The aim of this study was to follow-up growth-restricted patients after endoprosthetic treatment.

MATERIALS AND METHODS

138 knee arthroplasties in patients with a height ≤150 cm between January 1, 2000 and May 5, 2013 at our institution were enrolled in this study. 124 cases were available for 1-year follow-up. Out of these, 43 cases were available for 5-year follow-up so far. 14 patients were lost to follow-up.

RESULTS

IKS score increased from 35 ± 16 on admission to 67 ± 22 (p < 0.001) at 1-year follow-up and 65 ± 23 (p < 0.001) at 5-year follow-up. Function Score increased from 40 ± 29 on admission to 64 ± 21 (p < 0.001) at 1-year follow-up and 63 ± 23 (p < 0.001) at 5-year follow-up. Revision surgery was required in one case (0.8 %) after 1-year follow-up, and in an additional three cases (7 %) after 5-year follow-up.

CONCLUSIONS

Knee arthroplasty can be performed in patients suffering from dwarfism with good clinical benefits. However, survival rates are worse compared to the general population.

Novel genetic variants in the TPO gene cause congenital hypothyroidism

BACKGROUND

Mutations in the dual oxidase maturation factor 2 (DUOXA2) and thyroid peroxidase (TPO) genes have been reported to cause goitrous congenital hypothyroidism (GCH). The aim of this study was to determine the genetic basis of GCH in affected children.

METHODS

Thirty children with GCH were enrolled for molecular analysis of the DUOXA2 and TPO genes. All subjects underwent clinical examination and laboratory testing. Genomic DNA was extracted from peripheral blood leukocytes, and Sanger sequencing was used to screen for DUOXA2 and TPO gene mutations in the exon fragments amplified from the extracted DNA. Family members of those patients with mutations were also enrolled and evaluated.

RESULTS

Analysis of the TPO gene revealed six genetic variants, including two novel heterozygous mutations, c.1970T> C (p.I657T) and c.2665G> T (p.G889X), and four mutations that have been reported previously (c.670_672del, c.2268dup, c.2266T> C and c.2647C> T). Three patients harbored the same mutation c.2268dup. The germline mutations from four unrelated families were consistent with an autosomal recessive inheritance pattern. Conversely, no mutations in the DUOXA2 gene were detected.

CONCLUSION

Two novel inactivating mutations (c.1970T> C and c.2665G> T) in the TPO gene were identified. The c.2268dup mutation occurred frequently. No mutations in the DUOXA2 gene were detected in this study.