High prevalence of associated birth defects in congenital hypothyroidism

Retrospective Examination of Infants With Congenital Neural Tube Defect

INTRODUCTION

In the present study, neonates presenting with neural tube defects (NTDs) and undergoing observation within the confines of the neonatal intensive care unit (NICU) were subjected to a comprehensive assessment encompassing concurrent morbidities, clinical manifestations, laboratory parameters, and instituted interventions.

MATERIALS AND METHODS

A retrospective examination was conducted on the medical records of 135 neonates diagnosed with congenital NTD within the temporal span from 2008 to 2018. The study cohort was drawn from the NICU of the Health Sciences University Erzurum Regional and Research Hospital Health Practice and Research Center.

DISCUSSION

The current investigation encompasses a retrospective analysis of 135 patients diagnosed with NTD who received treatment at the NICU between the years 2008 and 2018. Among these, 74 individuals (54.2%) were male, while 61 (45.8%) were female. Maternal ages ranged from 17 to 46 years, with variations in the number of pregnancies, ranging from 1 to 10. Notably, 71 cases (52.6%) were delivered through normal spontaneous delivery, whereas 64 cases (47.4%) underwent cesarean section. The familial context revealed that five patients (3.6%) had siblings with a history of NTD, while no instances were noted where mothers had received antenatal folic acid support. Birth weights of the neonates ranged from 1425 to 4500 grams. Consanguinity was identified in the parental relationships of 17 cases (12.6%). The average diameter of the neural tube sac was determined to be 4.83 ± 1.94 cm (1-12 cm). Predominantly, the lumbosacral region emerged as the most common site of NTD, with meningomyelocele being the prevailing NTD type. Hydrocephalus coexisted in 67 cases, and notably, 44 instances exhibited the development of hydrocephalus post-sac operation. Eight patients were deemed inoperable, and the initial surgery transpired at an average age of 4.3 ± 2.6 (0-17) days. Flap closure constituted 32 of the surgical interventions, while primary closure was implemented in 95 cases. Neurogenic bladder antedated the operation in 14 patients, and 12 individuals developed neurogenic bladder postoperatively. Ventriculoperitoneal shunt placement was warranted in 47 patients. The average duration of hospitalization was 22.5 ± 14.4 days. Regrettably, three patients died due to complications and infections during their hospital stay.

RESULT

NTD represents a significant cohort of pathologies necessitating a comprehensive and interdisciplinary management strategy. These anomalies are characterized by elevated morbidity and mortality rates, not only exerting substantial financial strains on societal, familial, and state healthcare resources but also inflicting profound emotional distress upon affected families. Crucially, periconceptional strategies emphasizing balanced nutrition coupled with targeted multivitamin and mineral supplementation, particularly the inclusion of folic acid, assume paramount importance in the prophylaxis of this debilitating condition.

Patent ductus arteriosus in a late preterm neonate: think congenital hypopituitarism

A late preterm female neonate presented with initial respiratory distress and heart murmur attributed to a haemodynamically significant patent ductus arteriosus (hsPDA) not responding to two courses of ibuprofen. Thyroid function performed for prolonged neonatal jaundice at 3 weeks of life suggested central hypothyroidism. Subsequent adrenocorticotropic hormone stimulation test showing hypocortisolism and MRI revealing adenohypophysis hypoplasia confirmed the diagnosis of congenital hypopituitarism (CH). Commencement of hydrocortisone followed by thyroxine replacement coincided with clinical closure of the hsPDA within 72 hours of treatment. Hypothyroidism and hypocortisolism may have contributed to persistent hsPDA. Thyroid hormone increases cytochrome P450 activity, endothelin-1 and fibronectin expression. Hydrocortisone decreases sensitivity of ductus arteriosus to PGE2 These mechanisms have been postulated to cause ductal constriction and closure. Our case supports this association. hsPDA in a term and near-term neonate with a protracted disease course or associated midline defects should prompt the clinician to suspect CH (hypothyroidism and/or hypocortisolism).

Congenital Anomalies in Infant With Congenital Hypothyroidism: A Review of Pathogenesis, Diagnostic Options, and Management Protocols

Thyroid hormones (TH) regulate growth, nervous system myelination, metabolism, and physiologic functions in nearly every organ system. Congenital hypothyroidism (CH) is one of the most common endocrinopathies in children and has potentially devastating neurologic and developmental consequences. The etiology and clinical manifestations of hypothyroidism in children differ from adults. And hence, pediatric medical care requires a detailed understanding of thyroid function and dysfunction in children. The perinatal risk factors include female sex, preterm birth, low birth weight, postmature birth, additional birth abnormalities, and being delivered in multiple births. In countries where newborn screening is practiced, CH is detected after birth through screening tests. It aids in determining the underlying cause, though some patients may be able to start treatment without these tests. Early detection and treatment prevent irreversible and permanent nervous system damage. Thus, in addition to exploring the development of CH, this article has also covered the epidemiological data, clinical aspects, and management stemming from pediatric hypothyroidism.

Neonatal outcomes and congenital anomalies in pregnancies affected by hypothyroidism

BACKGROUND

Maternal hypothyroidism has been reported to have concerns over neonatal outcomes, not only in the context of neurocognitive development but also in the short term as birth weight and neonatal jaundice.

PATIENTS AND METHODS

We conducted a cross-sectional retrospective study on 638 cases who delivered live births in the Aga Khan University Hospital after ethical approval. Data were collected on hypothyroid pregnant females who were diagnosed before conception or during their antenatal visits during the year 2008-2016. Neonatal outcomes were noted for birth weight, maturity, and neonatal jaundice, neonatal hypothyroidism, neonatal respiratory distress syndrome, sepsis, hypocalcaemia, congenital anomalies, need for intensive care admission, and neonatal death. Subgroup analysis was performed on the timing of diagnosis of maternal hypothyroidism. Data analysis was performed on Statistical Package for the Social Sciences version 20.0.

RESULTS

Neonatal jaundice was the most common neonatal outcome (37.6%) in our cohort of 662 live births. Nearly 15% required intensive care unit admission, however, neonatal death was very rare. The most common clinically significant congenital anomalies were cardiovascular defects, whereas Mongolian spots were the commonest congenital condition to report. There is a statistically significant association between low birth weight (OR 1.86, 95% CI 1.0-3.2, p ≤ 0.05) and congenital anomalies (OR 2.39, 95% CI 1.4-4.0, p ≤ 0.05) with women diagnosed with hypothyroidism before pregnancy.

CONCLUSION

We report the neonatal outcomes and spectrum of congenital anomalies of hypothyroid pregnancies diagnosed before and during conception for the first time from the region of Pakistan.KEY MESSAGEOverall, none of the neonates of hypothyroid pregnancies developed congenital hypothyroidism.Cardiovascular defects in these neonates imply extensive screening and monitoring during pregnancy.Low birth weight and congenital anomalies are associated with the timings of diagnosis of hypothyroidism in pregnancy.

Incidence of primary congenital hypothyroidism and relationship between diagnostic categories and associated malformations

PURPOSE

The incidence of primary congenital hypothyroidism (CH) has grown progressively and literature data indicate an association between CH and congenital malformations. The purpose of this study is to establish the current incidence of CH in the Italian Region of Piedmont and verify the relationship between CH diagnostic categories and associated malformations.

METHODS

The biochemical and clinical data of 105 newborns with CH diagnosed in the period January 2014 to December 2019 were analyzed.

RESULTS

The incidence of CH in the Italian Piedmont region in the 2014-2019 period increased to 1:1090. Thyroid dysgenesis was responsible for 47.6% (50/105) of all cases, with agenesis in 14.3% (15/105), while ectopia and hypoplasia in 23.8% (25/105) and 9.5% (10/105) of the cases, respectively; dyshormonogenesis defects were found in 52.4% (55/105) of cases. Congenital extra-thyroid anomalies were identified in 33/105 (31.4%) of newborns with CH and mainly involve the cardiac system (17/85, 16.1%), urogenital tract (7/85, 6.7%), gastrointestinal tract (5/105, 4.8%), and the musculoskeletal system (5/105, 4.8%). The highest rate of malformations was observed in patients with thyroid agenesis and dyshormonogenesis, respectively, in 53.5% and 36.4% of cases, while in the presence of thyroid ectopia and hypoplasia, the rate was 12% and 20%, respectively, (p = 0.03).

CONCLUSION

In the Italian region of Piedmont, the incidence of primary CH has been increased over time, with a variation in the percentage of the different forms of CH. Congenital malformations, especially affecting the cardiovascular, urogenital, gastrointestinal, and musculoskeletal systems, seem to be mainly associated with thyroid agenesis or defects in hormonogenesis.

Congenital urogenital abnormalities in children with congenital hypothyroidism

Background: Congenital hypothyroidism (CH), as one of the most common congenital endocrine disorders, may be significantly associated with congenital malformations. This study investigates urogenital abnormalities in children with primary CH (PCH).

Methods: This case-control study was conducted on 200 children aged three months to 1 year, referred to Amir-Kabir Hospital, Arak, Iran. One hundred children with PCH, as the case group, and 100 healthy children, as the control group, were selected using convenient sampling. For all children, demographic data checklists were filled, and physical examination, abdomen and pelvic ultrasound and other diagnostic measures (if necessary) were performed to evaluate the congenital urogenital abnormalities including anomalies of the penis and urethra, and disorders and anomalies of the scrotal contents.

Results: Among 92 (100%) urogenital anomalies diagnosed, highest frequencies with 37 (40.2%), 26(28.2%) and 9 (9.7%) cases including hypospadias, Cryptorchidism, and hydrocele, respectively. The frequency of urogenital abnormalities among 32 children with PCH, with 52 cases (56.5%) was significantly higher than the frequency of abnormalities among the 21 children in the control group, with 40 cases (43.4%). (OR=2.04; 95%CI: 1.1-3.6; p=0.014).

Conclusion: Our study demonstrated that PCH is significantly associated with the congenital urogenital abnormalities. However, due to the lack of evidence in this area, further studies are recommended to determine the necessity of conducting screening programs for abnormalities of the urogenital system in children with CH at birth.

Detection of Novel Gene Variants Associated with Congenital Hypothyroidism in a Finnish Patient Cohort

BACKGROUND

Congenital hypothyroidism (CH) is defined as the lack of thyroid hormones at birth. Mutations in at least 15 different genes have been associated with this disease. While up to 20% of CH cases are hereditary, the majority of cases are sporadic with unknown etiology. Apart from a monogenic pattern of inheritance, multigenic mechanisms have been suggested to play a role in CH. The genetics of CH has not been studied in Finland so far. Therefore, multigenic sequencing of CH candidate genes was performed in a Finnish patient cohort with both familial and sporadic CH.

METHODS

A targeted next-generation sequencing (NGS) panel, covering all exons of the major CH genes, was applied for 15 patients with sporadic and 11 index cases with familial CH.

RESULTS

Among the familial cases, six pathogenic mutations were found in the TPO, PAX8, and TSHR genes. Furthermore, pathogenic NKX2.1 and TG mutations were identified from sporadic cases, together with likely pathogenic variants in the TG, NKX2.5, SLC26A4, and DUOX2 genes. All identified novel pathogenic mutations were confirmed by Sanger-sequencing and characterized in silico and/or in vitro.

CONCLUSION

In summary, the CH panel provides an efficient, cost-effective, and multigenic screening tool for both known and novel CH gene mutations. Hence, it may be a useful method to identify accurately the genetic etiology for dyshormogenic, familial, or syndromic forms of CH.

Congenital anomalies of kidney and upper urinary tract in children with congenital hypothyroidism; a case-control study

INTRODUCTION

Congenital hypothyroidism (CH) may be significantly associated with congenital malformations. However, there is little evidence on the relationship between renal and urinary tract anomalies and CH.

OBJECTIVES

The aim of this study was to compare the renal and upper urinary tract anomalies in children with and without primary CH (PCH).

PATIENTS AND METHODS

This case-control study was conducted on 200 children aged 3 months to 1 year, referring to Amir-Kabir hospital, Arak, Iran. One hundred children with PCH, as the case group, and 100 children without CH, as the control group, were selected. For all children, ultrasonography and other diagnostic measures (if necessary) were performed to evaluate renal and upper urinary tract anomalies (ureter and bladder).

RESULTS

The frequency of renal and upper urinary tract anomalies among 43 children with primary CH, with 83 cases (72.8%), was significantly higher than the frequency of anomalies among the 19 children in the control group, with 31 cases (27.1%) (OR = 3; CI 95%: 1.6-5.4; P = 0.001). Among the anomalies studied, only the differences in frequency of uretero-pelvic junction obstruction (UPJO) (OR = 6; CI 95%: 1.3-28; P = 0.018) and hydronephrosis (OR = 22; CI 95%: 5-95; P = 0.001) was significant between the two groups.

CONCLUSION

Our study demonstrated that PCH is significantly associated with the frequency of congenital anomalies of the kidneys and upper urinary tracts. However, further studies are recommended to determine the necessity of conducting screening programs for anomalies of the kidneys and urinary tract in children with CH at birth.

Thyroid dyshormonogenesis and associated non-thyroidal anomalies in a tertiary care hospital in India

BACKGROUND

Dyshormonogenetic goiter refers to familial goiters owing to an inherited defect in the metabolism of thyroid hormones.

METHODS

19 patients with clinical and biochemically proven hypothyroidism (low T3, FT4 and high TSH) were recruited for the study. All patients were subjected to (i) ultrasound of the neck to rule out thyroid dysgenesis and (ii) technetium-99m radionuclide thyroid scintigraphy and a perchlorate discharge test (PDT). Extrathyroidal malformations were identified by clinical ultrasound (USG) examination of the abdomen and pelvis and by echocardiography.

RESULTS

Out of 19 patients with elevated thyroid uptakes on technetium-99m thyroid scintigraphy, 12 (63%) had a positive PDT and 7 patients (37%) had a negative PDT. All patients were subjected to abdominopelvic USG and echocardiography. Out of 12 patients with a positive PDT, 5 (42%) had associated extrathyroid malformations, 2 had urogenital malformations, and cardiac abnormalities on echocardiography were present in 2 patients (17%). One patient (8%) had features of dysmorphism in the form of a high-arched palate, low-set ears and microcephaly.

CONCLUSION

Congenital hypothyroidism due to dyshormogenesis is associated with a high prevalence of extrathyroidal malformations and needs to be managed as early as possible to ensure normal neurocognitive development of the children affected.

A de novo 10.79 Mb interstitial deletion at 2q13q14.2 involving PAX8 causing hypothyroidism and mullerian agenesis: a novel case report and literature review

Reports of interstitial deletions involving proximal long arm of chromosome 2 are limited. Based on early chromosomal analysis studies, the phenotypic consequence of deletions at the ancestral chromosome fusion site at chromosome 2q13q14.1 remains unclear. A recurrent 1.71 Mb deletion at 2q13 has recently been proposed as a new genomic disorder, associated with an increased risk of intellectual disability and craniofacial dysmorphism. Herein, we report the case of a 12 year-old girl with unique clinical features including global developmental delay, mullerian agenesis, and hypothyroidism associated with a normal size and position of the thyroid gland, as well as negative thyroid antibodies. Microarray-based comparative genomic hybridization study revealed a de novo 10.79 Mb deletion at 2q13q14.2 (111,548,932–122,336,492), which involves more than 88 UCSC genes, 38 of which are OMIM genes, 7 of which are disease-causing and 3 of which (including GLI2, IL1B and PAX8) show a dominant inheritance pattern.. Interestingly, PAX8 (chr2:113,973,574–114,036,498), a member of the paired-box gene family, is essential for the formation of thyroxine-producing follicular cells. Autosomal dominant transmission of congenital thyroid hypoplasia due to loss-of-function mutation of PAX8 suggests a possible haploinsufficiency effect. Additionally, PAX8 is also expressed in the tissue primordia that form both the mullerian duct derivatives and the upper urinary tracts. A recent study has associated a novel PAX8 mutation with a severe form of hypothyroidism and abnormalities in the urogenital tract. Taken together, the unique clinical manifestation seen in this patient could be attributed to the heterozygous deletion of PAX8 gene. A prospective investigation is merited to fully evaluate the pathogenic effect of the interstitial deletion of 2q13q14.2.

Thyroid Function Test in Pre-term Neonates During the First Five Weeks of Life

BACKGROUND

Congenital hypothyroidism (CHT) is one of the most common congenital endocrinal disorders. The prevalence of CHT is estimated about 1 in 3,000 newborns. The prevalence, etiology and associated disorders of abnormal thyroid screening tests are reported in different ranges. In this study, we assessed the pre-term newborns for CHT and associated factors that influence thyroid function.

METHODS

One hundred newborns with the gestational age fewer than 35 weeks were investigated. Baseline serum thyroid stimulating hormone (TSH) and free thyroxin (FT4) levels were measured during the first 5 days of life and were repeated during the first 5 weeks. We analyzed the effects of demographic factors and the presence of respiratory distress syndrome on the alteration of thyroid function tests during the first 5 weeks of life.

RESULTS

The mean gestational age (GA) at delivery was 32.35í1.97 (range 28 to 35) weeks. CHT was observed in 13(13%) preterm infants. GA was the only factor which affect the FT4 changes over the two weeks follow-up (P < 0.001, b: -2.783, Power: 70.2%) although the differences between baseline and follow-up amount of TSH were not significantly influenced by GA (P = 0.062, power: 46%). However, the adjusted TSH and FT4 serum level changes during follow-up were significantly different between two groups (between CHT and normal, P = 0.006, 0.000, respectively).

CONCLUSIONS

It seems that thyroid function tests should be repeated in preterm infants, especially for patients with lower gestational age, to confirm the diagnosis of CHT. Also, CHT should be considered among the newborns that are affected by RDS.

Congenital hypothyroidism after assisted reproductive technology in Japan: comparison between multiples and singletons, 2005-2009

Background

The relationship between congenital hypothyroidism (CH) and multiple pregnancy has not been fully studied in Japan.

Methods

Complete nationwide data of assisted reproductive technology (ART) in Japan from 2005 to 2009 presented by the Japan Society of Obstetrics and Gynecology, which include information on CH and birth defects were used for analyses. Diseases were reclassified according to the International Classification of Diseases, tenth edition (ICD-10, 2003 version). The relative risk (RR) and 95% confidence interval (CI) of the incidence rate for CH was calculated with singletons as the reference group. Additional birth defects with CH were examined. The probandwise concordance rate of multiples and recurrence risk ratio were calculated.

Results

There were 18 patients with CH, consisting of 12 singletons and 6 multiples. The incidence rates of CH per 1,000 live births in singletons and multiples are 0.14 (=12/87,145) and 0.31 (=6/19,533), respectively. The incidence rate was more than twofold higher in multiple births than in singleton births, but the difference was not statistically significant (RR=2.2, 95% CI 0.8–5.9). Additional birth defects were present in three patients with CH (17%=3/18). The multiples were affected by other birth defects more frequently (33%=2/6) than the singletons (8%=1/12). The six multiple-births patients were derived from one concordant twin pair, which consisted of two twin patients; three discordant twin pairs, which consisted of three twin patients; and one discordant triplets set, which consisted of one triplet patient. Thus, the probandwise concordance rate was 33.3% (=2/(2+4)). The estimated recurrence risk ratio was 1976 (for the total ART population) or 609 (for the Japanese general population).

Conclusions

CH was more frequent in multiples compared to singletons. A higher percentage of additional birth defects was also observed in multiples compared to singletons. The familial aggregation of CH was suggested.

Congenital anomalies in infant with congenital hypothyroidism

OBJECTIVE

Congenital hypothyroidism is characterized by inadequate thyroid hormone production in newborn infants. Many infants with CH have co-occurring congenital malformations. This is an investigation on the frequency and types of congenital anomalies in infants with congenital hypothyroidism born from May 2006-2010 in Hamadan, west province of Iran.

METHODS

The Iranian neonatal screening program for congenital hypothyroidism was initiated in May 2005. This prospective descriptive study was conducted in infants diagnosed with congenital hypothyroidism being followed up in Pediatric Endocrinology Clinic of Besat Hospital, a tertiary care centre in Hamadan. Cases included all infants with congenital hypothyroidism diagnosed through newborn screening program or detected clinically. Anomalies were identified by clinical examination, echocardiography, and X-ray of the hip during the infant's first year of life.

RESULTS

A total of 150 infants with biochemically confirmed primary congenital hypothyroidism (72 females and 78 males) were recruited during the period between May 2006-2010. Overall, 30 (20%) infants had associated congenital anomalies. The most common type of anomaly was Down syndrome. Seven infants (3.1%) had congenital cardiac anomalies such as: ASD (n=3), VSD (n=2), PS (n =1), PDA (n=1). Three children (2.6%) had developmental dysplasia of the hip (n=3).

CONCLUSION

The overall frequency of Down syndrome, cardiac malformation and other birth defect was high in infants with CH. This reinforces the need to examine all infants with congenital hypothyroidism for the presence of associated congenital anomalies.

High prevalence of congenital hypothyroidism in Isfahan: Do familial components have a role?

Background:

Despite elimination of iodine deficiency, the rates of both permanent and transient congenital hypothyroidism (CH) in our study were higher than the comparable worldwide rates, which emphasize the major role of genetic factors in the pathogenesis of CH and many studies in this regard confirm this possibility.

Materials and Methods:

In this review, we report all studies that established during CH screening program regarding familial and genetic component of the disease.

Results:

Although we could not entirely ignore the possible role of environmental and autoimmune factors in the development and function of thyroid gland, our findings strongly suggest the role of genetic factors as dominant etiologic factor in CH.

Conclusion:

The studies support the existence of a familial component of CH involving dominant genetic predisposition factors with a low penetrance. Considering the polygenic/multifactorial basis of CH, they suggest the possible involvement of other unknown genes in the pathogenesis of the disease, which may also follow non-Mendelian pattern of inheritance.