Overview on neural tube defects: From development to physical characteristics

Brain development and bioenergetic changes

Bioenergetics describe the biochemical processes responsible for energy supply in organisms. When these changes become dysregulated in brain development, multiple neurodevelopmental diseases can occur, implicating bioenergetics as key regulators of neural development. Historically, the discovery of disease processes affecting individual stages of brain development has revealed critical roles that bioenergetics play in generating the nervous system. Bioenergetic-dependent neurodevelopmental disorders include neural tube closure defects, microcephaly, intellectual disability, autism spectrum disorders, epilepsy, mTORopathies, and oncogenic processes. Developmental timing and cell-type specificity of these changes determine the long-term effects of bioenergetic disease mechanisms on brain form and function. Here, we discuss key metabolic regulators of neural progenitor specification, neuronal differentiation (neurogenesis), and gliogenesis. In general, transitions between glycolysis and oxidative phosphorylation are regulated in early brain development and in oncogenesis, and reactive oxygen species (ROS) and mitochondrial maturity play key roles later in differentiation. We also discuss how bioenergetics interface with the developmental regulation of other key neural elements, including the cerebrospinal fluid brain environment. While questions remain about the interplay between bioenergetics and brain development, this review integrates the current state of known key intersections between these processes in health and disease.

Immunohistochemical and Histopathological Characterization of Spina Bifida Defect Tissues Removed After Prenatal and Postnatal Surgical Repair

Background: Myelomeningocele or spina bifida is an open neural tube defect that is characterized by protrusion of the meninges and the spinal cord through a deformity in the vertebral arch and spinous process. Myelomeningocele of post-natal tissue is well described; however, pre-natal tissue of this defect has no known previous histologic characterization. We compared the histology of different forms of pre-natal myelomeningocele and post-natal myelomeningocele tissue obtained via prenatal intrauterine and postnatal surgical repairs. Methods: Pre-and post-natal tissues from spina bifida repair surgeries were obtained from lipomyelomeningocele, myeloschisis, and myelomeningocele spina bifida defects. Tissue samples were processed for H&E and immunohistochemical staining (KRT14 and p63) to assess epidermal and dermal development. Results: Prenatal skin near the defect site develops with normal epidermal, dermal, and adnexal structures. Within the grossly cystic specimens, histology shows highly dense fibrous connective tissue with complete absence of a normal epidermal development with a lack of p63 and KRT14 expression. Conclusion: Tissues harvested from prenatal and postnatal spina bifida repair surgeries appear as normal skin near the defect site. However, cystic tissues consist of highly dense fibrous connective tissue with complete absence of normal epidermal development.

Craniorachischisis in a 33-week-old Female Fetus: A Case Report

We report the case of a 33-week-old female fetus born with craniorachischisis to a gravida 5, para 4 (3104) mother with no previous history of conceiving a child with a neural tube defect. Craniorachischisis is characterized by anencephaly and an open defect extending from the brain to the spine and is the most severe and fatal type of neural tube defect. Although the cause of neural tube defects is hypothesized to be multifactorial and is usually sporadic, the risk is increased in neonates born to mothers with a family history or a previous pregnancy with neural tube defect, both of which are not present in the index case. This case is unique in that only during the fifth pregnancy did the couple conceive a child with a neural tube defect, emphasizing that folic acid supplementation, the sole preventive measure proven to decrease the risk of neural tube defects, remains to be important in the periconceptual period for all women of childbearing age.

Exploring research hotspots and future directions in neural tube defects field by bibliometric and bioinformatics analysis

Background

Neural tube defects (NTDs) is the most common birth defect of the central nervous system (CNS) which causes the death of almost 88,000 people every year around the world. Much efforts have been made to investigate the reasons that contribute to NTD and explore new ways to for prevention. We trawl the past decade (2013-2022) published records in order to get a worldwide view about NTDs research field.

Methods

7,437 records about NTDs were retrieved from the Web of Science (WOS) database. Tools such as shell scripts, VOSviewer, SCImago Graphica, CiteSpace and PubTator were used for data analysis and visualization.

Results

Over the past decade, the number of publications has maintained an upward trend, except for 2022. The United States is the country with the highest number of publications and also with the closest collaboration with other countries. Baylor College of Medicine has the closest collaboration with other institutions worldwide and also was the most prolific institution. In the field of NTDs, research focuses on molecular mechanisms such as genes and signaling pathways related to folate metabolism, neurogenic diseases caused by neural tube closure disorders such as myelomeningocele and spina bifida, and prevention and treatment such as folate supplementation and surgical procedures. Most NTDs related genes are related to development, cell projection parts, and molecular binding. These genes are mainly concentrated in cancer, Wnt, MAPK, PI3K-Akt and other signaling pathways. The distribution of NTDs related SNPs on chromosomes 1, 3, 5, 11, 14, and 17 are relatively concentrated, which may be associated with high-risk of NTDs.

Conclusion

Bibliometric analysis of the literature on NTDs field provided the current status, hotspots and future directions to some extant. Further bioinformatics analysis expanded our understanding of NTDs-related genes function and revealed some important SNP clusters and loci. This study provided some guidance for further studies. More extensive cooperation and further research are needed to overcome the ongoing challenge in pathogenesis, prevention and treatment of NTDs.

Prenatal diagnosis and postnatal outcome of closed spinal dysraphism

OBJECTIVE

To evaluate the prenatal diagnosis of closed dysraphism (CD) and its correlation with postnatal findings and neonatal adverse outcomes.

METHODS

A retrospective cohort study including pregnancies diagsnosed with fetal CD by prenatal ultrasound (US) and magnetic resonance imaging (MRI) at a single tertiary center between September 2011 and July 2021.

RESULTS

CD was diagnosed prenatally and confirmed postnatally in 12 fetuses. The mean gestational age of prenatal imaging was 24.2 weeks, in 17% the head circumference was ≤fifth percentile and in 25% the cerebellar diameter was ≤fifth percentile. US findings included banana sign in 17%, and lemon sign in 33%. On MRI, posterior fossa anomalies were seen in 33% of cases, with hindbrain herniation below the foramen magnum in two cases. Mean clivus-supraocciput angle (CSA) was 74°. Additional anomalies outside the CNS were observed in 50%. Abnormal foot position was demonstrated prenatally in 17%. Neurogenic bladder was present in 90% of patients after birth.

CONCLUSION

Arnold Chiari II malformation and impaired motor function can be present on prenatal imaging of fetuses with CD and may be associated with a specific type of CD. Prenatal distinction of CD can be challenging. Associated extra CNS anomalies are frequent and the rate of neurogenic urinary tract dysfunction is high.

Prenatal imaging of the normal and abnormal spinal cord: recommendations from the Fetal Task Force of the European Society of Paediatric Radiology (ESPR) and the European Society of Neuroradiology (ESNR) Pediatric Neuroradiology Committee

Spinal dysraphisms are amenable to diagnosis in utero. The prognosis and the neonatal management of these conditions differ significantly depending on their types, mainly on the distinction between open and closed defects. A detailed evaluation not only of the fetal spine, but also of the brain, skull, and lower limbs is essential in allowing for the right diagnosis. In this article, recommendations from the Fetal Task Force of the European Society of Paediatric Radiology (ESPR) and the European Society of Neuroradiology (ESNR) Pediatric Neuroradiology Committee will be presented. The aim of this paper is to review the imaging features of the normal and abnormal fetal spinal cord, to clarify the prenatal classification of congenital spinal cord anomalies and to provide guidance in their reporting.

Profile of a Multivariate Observation under Destructive Sampling-A Monte Carlo Approach to a Case of Spina Bifida

A biodegradable hybrid polymer patch was invented at the University of Cincinnati to cover gaps on the skin over the spinal column of a growing fetus, characterized by the medical condition spina bifida. The inserted patch faces amniotic fluid (AF) on one side and cerebrospinal fluid on the other side. The goal is to provide a profile of the roughness of a patch over time at 0, 4, 8, 12, and 16 weeks with a 95% confidence band. The patch is soaked in a test tube filled with either amniotic fluid (AF) or phosphate-buffered saline (PBS) in the lab. If roughness is measured at any time point for a patch, the patch is destroyed. Thus, it is impossible to measure roughness at all weeks of interest for any patch. It is important to assess the roughness of a patch because the rougher the patch is, the faster the skin grows under the patch. We use a model-based approach with Monte Carlo simulations to estimate the profile over time with a 95% confidence band. The roughness profiles are similar with both liquids. The profile can be used as a template for future experiments on the composition of patches.

Multidisciplinary management of people with spina bifida across the lifespan

The average worldwide prevalence of neural tube defects (NTDs) is 1.0 per 1000 births. Its development is multifactorial due to genetic and non-genetic factors. Spina bifida (SB) is one of main representatives of NTD. The spinal cord lesion level is the main determinant of the level of paralysis, numbness, and difficulties with bladder/bowel functions. Myelomeningocele prenatal repair reduces hydrocephalus and hindbrain herniation and improves motor function. The severity of hydrocephalus is associated with poorer neurodevelopmental outcomes whether operated on prenatally or after birth. People with SB tend to have a lower IQ and cognitive difficulties. Early diagnosis, proactivity, and lifelong multidisciplinary follow-up are key protective issues. Invasive urological interventions should be considered in selected patients after failure of conservative treatment. Transition to adult care should be well planned as it is challenging. Health literacy is directly associated with success at transition. Sexuality and fertility should be addressed before/during puberty. Overall, the rates of fecal and urinary continence and skin breakdown increase with age, whereas the ability to ambulate declines with age. Bowel and urinary incontinence are independent predictors of lower health-related quality of life (HRQoL) in adults with SB. Bowel incontinence has negative impact on HRQoL regardless of frequency or amount. Long-term caregiver support should be offered at diagnosis. Survival at a mean of 50 years is poor, at 32%, due to central nervous system deaths, cancer, urological disease, and sepsis. Challenges to implementation of recommended practices exist, especially in low and middle-income countries.

Pharmacoeconomic Evaluation of Costs of Myelomeningocele and Meningocele Treatment and Screening

Background

The prevention of myelomeningocele (MMC) and meningocele (MC) is a public health concern. A systematic review on economic factors associated with MMC and MC can help the policy makers to evaluate the cost-effectiveness of screening and treatment. To our knowledge, this is the first systematic review to provide up-to date pharmacoeconomic evidence of all economic studies present in literature on different aspects of MMC and MC.

Methods

We searched in the National Health Service Economic Evaluation Database (NHSEED), PubMed, Cost-effectiveness Analysis Registry (CEA Registry), Centre for Reviews and Dissemination (CRD), Health Technology Assessment Database (HTAD), Cochrane Library, and Econlit. The PRISMA guidelines were followed in the search and evaluation of literature. Only articles in English not limited by the year of publication that fulfilled the eligibility criteria were included in this systematic review.

Results

Nineteen papers were included in the study. The studies were very heterogeneous and reported a comparison of the costs between prenatal versus postnatal repair, the cost of fetoscopic approach versus open surgery, the cost of ventriculoperitoneal shunting (VPS) versus endoscopic third ventriculostomy (ETV), and ETV with choroid plexus cauterization (ETV/CPC), the cost of hospitalization, and the cost of diagnosis for MMC.

Conclusion

The results of this study can help in implementing new policies in different countries to assist MC and MMC patients with the cost of treatment and screening.

Effect of cervical and lumbosacral spina bifida cystica on volumes of intracranial structures in children

PURPOSE

Spina bifida is a major disorder that occurs when the membranes of the spinal cord and medulla fail to close during the embryonic period and affects the individual for the rest of life. Some physical, mental, and social difficulties can be observed in the lives of children with spina bifida after surgery. The aim of this study is to determine what kind of volumetric changes occur in the brain when spina bifida occurs in different regions of the cord.

METHODS

The volume of intracranial structures of 14 children aged 1 to 9 years (7 cervical, 7 lumbosacral) with different levels of spina bifida compared with vol2Brain.

RESULTS

Spina bifida occurring in the cervical region was found to cause a greater volumetric reduction in subcortical structures, cortex and gyrus than spina bifida occurring in the lumbosacral region.

CONCLUSION

We believe that our study will help clinicians involved in the management of this disorder.

Molecular landscape of congenital vertebral malformations: recent discoveries and future directions

Vertebral malformations (VMs) pose a significant global health problem, causing chronic pain and disability. Vertebral defects occur as isolated conditions or within the spectrum of various congenital disorders, such as Klippel-Feil syndrome, congenital scoliosis, spondylocostal dysostosis, sacral agenesis, and neural tube defects. Although both genetic abnormalities and environmental factors can contribute to abnormal vertebral development, our knowledge on molecular mechanisms of numerous VMs is still limited. Furthermore, there is a lack of resource that consolidates the current knowledge in this field. In this pioneering review, we provide a comprehensive analysis of the latest research on the molecular basis of VMs and the association of the VMs-related causative genes with bone developmental signaling pathways. Our study identifies 118 genes linked to VMs, with 98 genes involved in biological pathways crucial for the formation of the vertebral column. Overall, the review summarizes the current knowledge on VM genetics, and provides new insights into potential involvement of biological pathways in VM pathogenesis. We also present an overview of available data regarding the role of epigenetic and environmental factors in VMs. We identify areas where knowledge is lacking, such as precise molecular mechanisms in which specific genes contribute to the development of VMs. Finally, we propose future research avenues that could address knowledge gaps.

Fetal and Placental Causes of Elevated Serum Alpha-Fetoprotein Levels in Pregnant Women

The most common association related to alpha-fetoprotein (AFP) is fetal neural tube defect (NTD), and indeed, this is where the international career of this protein began. In times when ultrasonography was not yet technically advanced, the detection of high levels of AFP in maternal serum (MS-AFP) and amniotic fluid was the basis for suspecting neural tube defects. In cases where there was no confirmation of NTD, other causes were sought. It has been established that high titers of MS-AFP could originate in other defects or diseases, such as (1) increased proteinuria in severe fetal kidney diseases; (2) pathological overproduction in liver diseases; (3) penetration through the membranes of gastrointestinal organs exposed to amniotic fluid; (4) passage through the walls of skin vessels; and as a side effect of (5) hepatic hematopoiesis and increased transfer through the edematous placenta in fetal anemia. This article provides a review of the current literature on congenital defects and genetic diseases in the fetus where an elevated level of MS-AFP may serve as the initial diagnostic clue for their detection.

Clinical presentation and outcomes of neonates born with neural tube defects- an experience from a level III B NICU in Western India

PURPOSE

Neural tube defects (NTDs) are one of the most common congenital anomalies and a cause of chronic disability. The study was done to study outcomes of neural tube defects admitted at a tertiary level neonatal intensive care unit (NICU) from 2018 to 2022, a period of 4 years that also coincided with the COVID pandemic. The secondary outcome was to study the clinical presentation, associated anomalies and epidemiological features.

METHODS

It was a retrospective observational study; data of infants was obtained from medical records and analysis was done.

RESULTS

Thirty-four neonates were enrolled, of which there were 16 (47%) males and 18 (53%) females. History of pre-pregnancy maternal folate intake was present in 4 (11.7%) cases. 33 (97%) babies were diagnosed with meningomyelocele (MMC) and one each had anencephaly, iniencephaly and encephalocele, of which one had frontal and two had occipital encephalocele. The median age of surgery was 16 days of life with primary repair being the most common procedure followed by MMC repair with VP shunt. Twenty babies (58.8%) were discharged successfully, while 9 (26.5%) expired and 5 (14.7%) were discharged against medical advice; which can be attributed to the financial problems of the patients in a developing country. The overall deaths in our series were four (26.5%) which is slightly higher than other studies which may be due to the fact that this study was conducted during the COVID era with lesser rates of folate supplementation, reduced access to prenatal diagnosis coupled with poor follow-up and compliance of patients post-surgical repair.

CONCLUSION

This study emphasizes the importance of periconceptional folic acid supplementation, prenatal diagnosis, early surgery and meticulous follow-up as being pivotal to improving outcomes in children with NTDs.

Valproic Acid in Pregnancy Revisited: Neurobehavioral, Biochemical and Molecular Changes Affecting the Embryo and Fetus in Humans and in Animals: A Narrative Review

Valproic acid (VPA) is a very effective anticonvulsant and mood stabilizer with relatively few side effects. Being an epigenetic modulator, it undergoes clinical trials for the treatment of advanced prostatic and breast cancer. However, in pregnancy, it seems to be the most teratogenic antiepileptic drug. Among the proven effects are congenital malformations in about 10%. The more common congenital malformations are neural tube defects, cardiac anomalies, urogenital malformations including hypospadias, skeletal malformations and orofacial clefts. These effects are dose related; daily doses below 600 mg have a limited teratogenic potential. VPA, when added to other anti-seizure medications, increases the malformations rate. It induces malformations even when taken for indications other than epilepsy, adding to the data that epilepsy is not responsible for the teratogenic effects. VPA increases the rate of neurodevelopmental problems causing reduced cognitive abilities and language impairment. It also increases the prevalence of specific neurodevelopmental syndromes like autism (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). High doses of folic acid administered prior to and during pregnancy might alleviate some of the teratogenic effect of VPA and other AEDs. Several teratogenic mechanisms are proposed for VPA, but the most important mechanisms seem to be its effects on the metabolism of folate, SAMe and histones, thus affecting DNA methylation. VPA crosses the human placenta and was found at higher concentrations in fetal blood. Its concentrations in milk are low, therefore nursing is permitted. Animal studies generally recapitulate human data.

Exencephaly-Anencephaly Sequence Associated with Maxillary Brachygnathia, Spinal Defects, and Palatoschisis in a Male Domestic Cat

Anencephaly, a severe neural tube defect characterized by the absence of major parts of the brain and skull, is a rare congenital disorder that has been observed in various species, including cats. Considering the uncommon appearance of anencephaly, this paper aims to present anencephaly in a stillborn male kitten from an accidental inbreeding using various paraclinical methods. Histological examination of tissue samples from the cranial region, where parts of the skull were absent, revealed the presence of atypical nerve tissue with neurons and glial cells organized in clusters, surrounded by an extracellular matrix and with an abundance of blood vessels, which are large, dilated, and filled with blood, not characteristic of nerve tissue structure. In CT scans, the caudal part of the frontal bone, the fronto-temporal limits, and the parietal bone were observed to be missing. CT also revealed that the dorsal tubercle of the atlas, the dorsal neural arch, and the spinal process of the C2-C7 bones were missing. In conclusion, the kitten was affected by multiple congenital malformations, a combination of exencephaly-anencephaly, maxillary brachygnathism, closed cranial spina bifida at the level of cervical vertebrae, kyphoscoliosis, palatoschisis, and partial intestinal atresia. The importance of employing imaging techniques cannot be overstated when it comes to the accurate diagnosis of neural tube defects.

Folate deficiency reduced aberrant level of DOT1L-mediated histone H3K79 methylation causes disruptive SHH gene expression involved in neural tube defects

BACKGROUND

Neural tube defects (NTDs) are one of the most severe congenital abnormalities characterized by failures of the neural tube to close during early embryogenesis. Maternal folate deficiency could impact the occurrence of NTDs, however, the mechanisms involved in the cause of NTDs are poorly defined.

RESULTS

Here, we report that histone H3 methyltransferase disruptor of telomeric silencing 1-like (DOT1L) expression was significantly downregulated, and low levels of H3K79me2 were found in the corresponding NTDs samples with their maternal serum folate under low levels. Using ChIP-seq assays, we found that a decrease of H3K79me2 downregulates the expression of Shh and Sufu in mouse embryonic stem cells (mESC) under folate deficiency. Interestingly, folate antagonist methotrexate treatment led to attenuation of H3K79me2 due to Dot1l, affecting Shh and Sufu genes regulation. Upon further analysis, we find that the genes Shh and Sufu are both downregulated in the brain tissues of mice and humans with NTDs. There was a positive correlation between the transcription levels of Shh, Sufu and the protein levels of DOT1L by Pearson correlation analysis.

CONCLUSION

Our results indicate that abnormal Shh and Sufu genes expression reduced by aberrant Dot1l-mediated H3K79me2 levels could be the cause of NTDs occurrence.

Determinants of neural tube defects among women who gave birth in hospitals in Eastern Ethiopia: evidence from a matched case control study

INTRODUCTION

Neural tube defects (NTDs) are severe birth defects caused by nutritional, genetic or environmental factors. Because NTDs continue to have a significant health and economic impact on children and community at large, it is crucial to investigate potential risk factors in order to develop novel approaches to NTDs prevention. Determinants for the development of NTDs differ by country, region as well as within the country. The objective of this study was to identify the determinants of NTDs among newborns delivered in three hospitals found in eastern Ethiopia.

METHODS

A hospital-based matched case-control study was conducted among 138 cases and 138 control women who delivered in three teaching hospitals in Eastern Ethiopia in 2021. Data were collected using a structured and pre-tested interviewer-administered questionnaire. Cases were mothers who delivered a neonate with any type of NTDs regardless of gestational age or fetal viability, whereas controls were mothers who delivered an apparently healthy newborn. Chi-square was used to assess the significant difference between the two groups. Conditional logistic regression model was used to generate adjusted odds ratio with its corresponding 95% confidence intervals and compare the two groups.

RESULTS

Anencephaly (51.4%) and spinal bifida (34.1%) were the most frequently observed NTDs. None of study participants took preconception folic acid supplementation. Being a non-formal mothers (AOR = 0.34, 95% CI: 0.12-0.92, P = 0.034), rural residence, (AOR = 3.4, 95% CI: 1.18-9.78, P = 0.023), history of spontaneous abortion (AOR = 2.95, 95% CI: 1.15-7.55, P = 0.023), having severe anemia (AOR = 3.4, 95% CI: 1.17-9.87, P = 0.024), history of fever or cold (AOR = 2.75; 95% CI: 1.05-7.15, P = 0.038), and an exposure to various agro-chemicals (AOR = 3.39, 95% CI: 1.11-10.3, P = 0.032) were independent determinants of NTDs.

CONCLUSION AND RECOMMENDATION

In this study, NTDs were associated to several determinant factors in the area, including residential area, history of spontaneous abortion, severe anemia, fever/cold, antibiotic use before or during early pregnancy, and exposure to agrochemicals. Addressing the identified determinants is critical in averting the incidence of NTDs in the study area. Moreover, more research is needed to investigate women's dietary practices as well as the practice of preconception folic acid supplementation for pregnant women in Ethiopia's current health care system.

Ultrasound-Guided Prospective Screening for Spinal Dysraphism in Offspring of Mothers With Pregestational Diabetes: A Pilot Study

AIM

Determine the utility of prospective spinal ultrasound in infants of mothers with pregestational diabetes (PGDM) for the diagnosis of closed spinal dysraphism (SDs).

METHODS

This prospective observational pilot study was completed at a tertiary care center between May 1, 2020 and December 30, 2022. Infants born to mothers with PGDM and with normal spinal physical examinations were included. A total of 25 mother-infant dyads were enrolled in the study and prospectively screened with spinal ultrasound. The study was registered on ClinicalTrials.gov (Identifier-NCT05033275).

RESULTS

Twenty-five spinal ultrasounds were performed over the course of this study with three (8%) resulting in abnormal findings that required further imaging. Follow-up with magnetic resonance imaging found one case of tethered cord syndrome.

CONCLUSION

Prospective screening in infants of mothers with PGDM found one case of tethered cord syndrome. This finding suggests that risk stratified screening of mothers with diabetes might be a reasonable approach to care.

Transcriptional Signature of Valproic Acid-Induced Neural Tube Defects in Human Spinal Cord Organoids

In vertebrates, the entire central nervous system is derived from the neural tube, which is formed through a conserved early developmental morphogenetic process called neurulation. Although the perturbations in neurulation caused by genetic or environmental factors lead to neural tube defects (NTDs), the most common congenital malformation and the precise molecular pathological cascades mediating NTDs are not well understood. Recently, we have developed human spinal cord organoids (hSCOs) that recapitulate some aspects of human neurulation and observed that valproic acid (VPA) could cause neurulation defects in an organoid model. In this study, we identified and verified the significant changes in cell-cell junctional genes/proteins in VPA-treated organoids using transcriptomic and immunostaining analysis. Furthermore, VPA-treated mouse embryos exhibited impaired gene expression and NTD phenotypes, similar to those observed in the hSCO model. Collectively, our data demonstrate that hSCOs provide a valuable biological resource for dissecting the molecular pathways underlying the currently unknown human neurulation process using destructive biological analysis tools.

Birth prevalence and risk factors of neural tube defects in Ethiopia: a systematic review and meta-analysis

OBJECTIVE

This study aims to estimate the prevalence of neural tube defects (NTDs) and to identify potential risk factors in the Ethiopian context.

STUDY DESIGN

Systematic review and meta-analysis.

STUDY PARTICIPANTS

A total of 611 064 participants were included in the review obtained from 42 studies.

METHODS

PubMed (Medline), Embase and Cochrane Library databases in combination with other potential sources of literature were systematically searched, whereby studies conducted between January 2010 and December 2022 were targeted in the review process. All observational studies were included and heterogeneity between studies was verified using Cochrane Q test statistics and I2 test statistics. Small study effects were checked using Egger's statistical test at a 5% significance level.

RESULT

The pooled prevalence of all NTDs per 10 000 births in Ethiopia was 71.48 (95% CI 57.80 to 86.58). The between-study heterogeneity was high (I2= 97.49%, p<0.0001). Birth prevalence of spina bifida (33.99 per 10 000) was higher than anencephaly (23.70 per 10 000), and encephalocele (4.22 per 10 000). Unbooked antenatal care (AOR 2.26, 95% CI (1.30 to 3.94)), preconception intake of folic acid (AOR 0.41, 95% CI (0.26 to 0.66)), having chronic medical illness (AOR 2.06, 95% CI (1.42 to 2.99)), drinking alcohol (AOR 2.70, 95% CI (1.89 to 3.85)), smoking cigarette (AOR 2.49, 95% CI (1.51 to 4.11)), chewing khat (AOR 3.30, 95% CI (1.88 to 5.80)), exposure to pesticides (AOR 3.87, 95% CI (2.63 to 5.71)), maternal age ≥35 (AOR 1.90, 95% CI (1.13 to 3.25)), maternal low educational status (AOR 1.60, 95% CI (1.13 to 2.24)), residing in urban areas (AOR 0.75, 95% CI (0.58 to 0.97))and family history of NTDs (AOR 2.51, 95% CI (1.36 to 4.62)) were associated with NTD cases.

CONCLUSION

The prevalence of NTDs in Ethiopia is seven times as high as in other Western countries where prevention measures are put in place. Heredity, maternal and environmental factors are associated with a high prevalence of NTDs. Mandatory fortification of staple food with folic acid should be taken as a priority intervention to curb the burden of NTDs. To smoothen and overlook the pace of implementation of mass fortification, screening, and monitoring surveillance systems should be in place along with awareness-raising measures.

PROSPERO REGISTRATION NUMBER

CRD42023413490.

Reducing the Risk of Birth Defects Associated with Maternal Influenza: Insights from a Hungarian Case-Control Study

Influenza viruses can cause several complications during pregnancy. Therefore, we aimed to investigate the effects of influenza on the development of congenital abnormalities (CAs) by analyzing the database of the Hungarian Case-Control Surveillance of Congenital Abnormalities (HCCSCA). In our multicenter, case-control, population-based study, we processed clinician-reported outcomes and diagnoses collected in the HCCSCA. The case group included newborns with different non-chromosomal birth defects, while the controls were newborns without CAs. Maternal influenza, as a risk factor for CAs, was analyzed by using a logistic regression model and odds ratios with 95% confidence intervals (CIs). Our results showed that maternal influenza in the first trimester was associated with increased odds of developing non-chromosomal CAs (OR: 1.41, CI: 1.28-1.55). There were increased odds of neural tube defects (OR: 2.22, CI: 1.78-2.76), orofacial clefts (OR: 2.28, CI: 1.87-2.78), and congenital heart defects (OR: 1.28, CI: 1.10-1.49) after influenza infection. In all cases, we found a protective effect of folic acid supplementation in the first trimester. In summary, the odds of non-chromosomal birth defects are higher after maternal influenza in the first trimester, and folic acid or pregnancy vitamin supplementation and antipyretic therapy may reduce the effect of maternal influenza during the first trimester.

Antiretroviral Regimen and Pregnancy Outcomes of Women Living with HIV in a US Cohort

Women who are pregnant and living with HIV have traditionally been excluded from clinical trials regarding new pharmacotherapy. Immediate initiation of antiretroviral therapy (ART) is recommended for women who are pregnant and living with HIV. Integrase inhibitors (INSTIs) are first-line recommended agents as they lead to more rapid HIV viral load reduction. We conducted a retrospective study of women who are pregnant and living with HIV who received prenatal care at the University of Washington. Mothers were categorized by ART class: INSTI, protease inhibitors (PI), and non-nucleoside reverse transcriptase inhibitors (NNRTI). Chi-square and t-tests were used for the analysis of baseline characteristics, and generalized estimating equations were used to adjust for HIV viral suppression between groups. There were a total of 234 mother-infant pairs whose pregnancies progressed beyond 20 weeks. The study demonstrated that women on INSTI regimens were more likely to have a shorter time to viral load suppression than women on NNRTI regimens. Additionally, seven congenital anomalies were identified in this cohort, none of which were neural tube defects. There was no perinatal transmission of HIV to any of the infants. This small cohort of women provides high-quality data regarding the safety and efficacy of INSTI use for both mothers and infants in resource-rich settings.

Neighborhood Deprivation and Neural Tube Defects

BACKGROUND

Individual measures of socioeconomic status (SES) have been associated with an increased risk of neural tube defects (NTDs); however, the association between neighborhood SES and NTD risk is unknown. Using data from the National Birth Defects Prevention Study (NBDPS) from 1997 to 2011, we investigated the association between measures of census tract SES and NTD risk.

METHODS

The study population included 10,028 controls and 1829 NTD cases. We linked maternal addresses to census tract SES measures and used these measures to calculate the neighborhood deprivation index. We used generalized estimating equations to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) estimating the impact of quartiles of census tract deprivation on NTDs adjusting for maternal race-ethnicity, maternal education, and maternal age at delivery.

RESULTS

Quartiles of higher neighborhood deprivation were associated with NTDs when compared with the least deprived quartile (Q2: aOR = 1.2; 95% CI = 1.0, 1.4; Q3: aOR = 1.3, 95% CI = 1.1, 1.5; Q4 (highest): aOR = 1.2; 95% CI = 1.0, 1.4). Results for spina bifida were similar; however, estimates for anencephaly and encephalocele were attenuated. Associations differed by maternal race-ethnicity.

CONCLUSIONS

Our findings suggest that residing in a census tract with more socioeconomic deprivation is associated with an increased risk for NTDs, specifically spina bifida.

Global, regional, and national epidemiological trends in neural tube defects between 1990 and 2019: a summary

BACKGROUND

Neural tube defects (NTD), such as spina bifida, are surgically treatable and primarily preventable non-communicable diseases. How incidence, mortality and disability-adjusted life year (DALYs) rates of NTD have modulated over time is not well defined. Correspondingly, the aim of this study was to quantitively define the global, regional, and national epidemiological trends in these.

METHODS

A retrospective review of data from the Global Burden of Disease Study 2019 Database was performed. Global, regional, and national outcomes for NTD were collected for incidence, mortality, and DALY rates and their age-standardized metrics analyzed. There were 7 regions at a regional level, and 204 countries and territories at a national level.

RESULTS

Globally, the latest age-standardized rates of incidence, mortality, and DALYs of NTD were 2.1 per 100,000 population, 1.3 per 1000,000, and 117 per 100,000 respectively. All rates demonstrated decreases in the last two decades to now. Regionally, sub-Saharan Africa and North America demonstrated the highest and lowest age-standardized rates of incidence (4.0 vs 0.5 per 100,000), mortality (3.0 vs 0.4 per 100,000), and DALYs (266 vs 33 per 100,000), respectively. Similar to global trends, all regions demonstrated decrease in these rates over the last two decades. Nationally, the highest age-standardized rates were reported in African countries, Central African Republic, with highest incidence rate (7.6 per 100,000), and Burkina Faso with highest mortality rate (5.8 per 100,000) and DALY rate (518 per 100,000). India was the country with the highest number of new NTD cases (22,000 per country) in the most recent year of study. Between 1990 and 2019, 182/204 (89%), 188/204 (92%), and 188/204 (92%) countries and territories demonstrated a decrease in age-standardized incidence, mortality, and DALY rates respectively, with the greatest decreases seen in Saudi Arabia for all statistics.

CONCLUSIONS

Between 1990 and 2019, overall trends in incidence, mortality, and DALY rates of NTD have been favorably downtrending globally. Regionally, these rates in the highest sub-Saharan Africa were 8 times greater compared to the lowest North America. Nationally, although the majority of countries showed decreases in these rates, a small number of countries demonstrated uptrending rates of NTD. Understanding the mechanics behind these trends will allow future public health endeavors for both prevention and neurosurgical treatment to be targeted appropriately.

A Brief Overview of Recent Pediatric Physical Therapy Practices and Their Importance

Recent years have seen a substantial increase in interest in pediatric physical therapy, which is a reflection of improvements in its methods and the rising understanding of its significance in child development and rehabilitation. This review provides a concise overview of the latest trends and techniques in pediatric physical therapy, emphasizing the integration of innovative technologies, evidence-based interventions, and holistic approaches. For children with varied developmental, congenital, and acquired disorders, the significance of early intervention and individualized treatment programs is emphasized, underlining the important influence of prompt interventions on long-term functional results and quality of life. To guarantee comprehensive and coordinated care, the study also examines the interdisciplinary character of pediatric physical therapy placing special emphasis on collaboration with families, caregivers, educators, and healthcare professionals. It also emphasizes the importance of continuing research, instruction, and lobbying to improve the effectiveness and availability of pediatric physical therapy services, eventually promoting the overall well-being of kids and their families.

The Relationship Between Fetal Central Nervous System Malformations and Modified Myocardial Performance Index

INTRODUCTION

Fetal ventriculomegaly, the most commonly identified abnormality of the fetal central nervous system (CNS), has been associated with elevated levels of the modified myocardial performance index (mMPI). However, the impact of other CNS pathologies on mMPI has not yet been evaluated. This study aimed to investigate whether there were changes in the myocardial performance index of fetuses with CNS pathologies without congenital heart diseases.

METHODS

A total of 126 singleton pregnant women were included in this study. Sixty-three fetuses had fetal CNS abnormalities of acrania, anencephaly, encephalocele, Dandy-Walker malformation, hydrocephalus, and meningocele. The control group consisted of 63 healthy and gestational age-matched fetuses. All ultrasonographic examinations were done in the second trimester of gestation. The data related to the characteristics of pregnant women were evaluated, and fetal left ventricular mMPI was obtained by ultrasound scan.

RESULTS

The study and the control group participants were not significantly different by means of pregnancy characteristics. The mean mMPI was higher in the fetal CNS malformation group compared to the control groups (0.39±0.02 vs. 0.45±0.04, P<0.001). The mean mMPI value was similar for fetuses with both closed and open calvarium defects of fetal CNS malformation.

CONCLUSION

Fetal CNS anomalies may be associated with prenatal cardiac dysfunction. Moreover, this relationship might be independent of the type of fetal CNS malformation, whether a closed or open calvarium defect.

Arnold-Chiari Malformations in Pregnancy and Labor: Challenges and Management Strategies

Arnold-Chiari malformations (ACMs) present unique challenges in pregnancy and labor, requiring a comprehensive understanding and multidisciplinary approach to care. This review article provides an overview of ACMs, including their definition, classification, and prevalence. The challenges in diagnosing ACMs during pregnancy, the available imaging modalities, and screening recommendations are discussed. The impact of ACMs on maternal health, fetal development, and the management strategies employed during pregnancy and labor are explored. Emphasis is placed on the importance of a multidisciplinary approach involving neurologists, obstetricians, and other specialists. Medical management options for symptom relief, surgical interventions, and anesthetic considerations during labor and delivery are also addressed. The importance of postpartum care, breastfeeding considerations, and long-term follow-up for women with ACMs who desire future pregnancies are highlighted. Finally, areas for further research and advancements in ACM management are identified. By improving our understanding and management of ACMs in pregnancy and labor, healthcare professionals can optimize care and improve outcomes for mothers and babies affected by this condition.

Does the Micronutrient Molybdenum Have a Role in Gestational Complications and Placental Health?

Molybdenum is an essential trace element for human health and survival, with molybdenum-containing enzymes catalysing multiple reactions in the metabolism of purines, aldehydes, and sulfur-containing amino acids. Recommended daily intakes vary globally, with molybdenum primarily sourced through the diet, and supplementation is not common. Although the benefits of molybdenum as an anti-diabetic and antioxidant inducer have been reported in the literature, there are conflicting data on the benefits of molybdenum for chronic diseases. Overexposure and deficiency can result in adverse health outcomes and mortality, although physiological doses remain largely unexplored in relation to human health. The lack of knowledge surrounding molybdenum intake and the role it plays in physiology is compounded during pregnancy. As pregnancy progresses, micronutrient demand increases, and diet is an established factor in programming gestational outcomes and maternal health. This review summarises the current literature concerning varied recommendations on molybdenum intake, the role of molybdenum and molybdoenzymes in physiology, and the contribution these play in gestational outcomes.

Neural tube defects: a review of global prevalence, causes, and primary prevention

Neural tube defects (NTDs) are common birth defects and contribute to life-long disabilities, high medical care costs, and perinatal and child mortality. This review is a primer on prevalence, causes, and evidence-based prevention strategies for NTDs. The estimated average global prevalence of NTDs is two cases per 1000 births, amounting to approximately 214,000-322,000 affected pregnancies worldwide annually. Prevalence and associated adverse outcomes are disproportionately high in developing countries. NTDs have multiple risk factors including genetic and non-genetic (i.e., maternal nutritional status, pre-pregnancy diabetes, early pregnancy exposure to valproic acid (anti-epileptic medication), and a previous pregnancy affected by a NTD) factors. Maternal folate insufficiency before and during early pregnancy is the most common risk factor and is preventable. Folic acid (vitamin B9) is required for formation of the neural tube early in pregnancy, around 28 days after conception, when most women are unaware of their pregnancies. Current guidelines recommend that all women planning or capable of pregnancy take a daily supplement containing 400-800 μg of folic acid. Mandatory folic acid fortification of staple foods (e.g., wheat flour, maize flour, rice) is safe, economical, and the effective intervention for primary prevention of NTDs. Currently, about 60 countries are implementing mandatory folic acid fortification of staple foods, preventing just a quarter of all preventable NTD cases worldwide. There is an urgent need for active champions, including neurosurgeons and other healthcare providers, to generate political will and promote effective mandatory food fortification with folic acid, and reach equitable primary prevention of NTDs in all countries.

Estimating the Glomerular Filtration Rate in Pediatric Patients With Neurogenic Bladder: A Comparison Between Creatinine- and Cystatin C-Equations

Background and objective Patients with neurogenic bladder (NB) are at a higher risk of developing chronic kidney disease (CKD). Due to their lower muscle mass, the estimated glomerular filtration rate (eGFR) based on creatinine (Cr) may be overestimated and delay the diagnosis of renal failure. This study compared eGFR calculated with different equations based on Cr and/or cystatin C (CysC) in children with NB, and the differences between patients with lower muscle mass (underdeveloped lower limbs) and those with independent gait (less muscle depletion). Methods We calculated the eGFR in pediatric patients with NB and CKD stages 1 and 2 by using the following equations: Chronic Kidney Disease in Children equation for serum creatinine (CKiD-Cr), CKiD-CysC, CKiD combined-Cr/CysC, Zappitelli-CysC, and Zappitelli combined-Cr/CysC. Results We evaluated a total of 47 patients, 74.5% with CKD stage 1, with a median age of 14.1 years. Of these participants, 59.6% had lipo/myelomeningocele. The CKiD-Cr and CysC-based equations led to significantly lower calculated eGFR ​​(p<0.05), specifically CKiD-CysC (p<0.001), Zappitelli-CysC (p<0.001), CKiD-Cr/CysC (p<0.001), and Zappitelli combined-Cr/CysC (p<0.05). When CKiD-CysC was used, 68% of the patients moved to a more advanced CKD stage. In patients without independent gait, with lower muscle mass (55.3%), the median eGFR calculated using the CKiD-Cr and CKiD combined-Cr/CysC equations was significantly higher (p<0.05). However, there were no differences between the two groups when using the other CysC-based equations. Conclusion In patients with NB and poor muscle mass, the CKiD-Cr equation may overestimate renal function. CysC-based equations seem more reliable in these patients, especially in those with greater muscular atrophy.

Genotoxicity and maternal-fetal safety of the dried extract of leaves of Azadirachta indica A. Juss (Meliaceae) in Wistar rats

ETHNOPHARMACOLOGICAL RELEVANCE

Azadirachta indica A. Juss (Meliaceae), popularly known as "neem", is used for the treatment of rheumatism, cancer, ulcers, diabetes, respiratory problems, among others. This species is present on six continents and contains more than 400 bioactive compounds. Practically all parts of the plant are used in the treatment of diseases. Although it is widely used, no study has evaluated the safety of this species throughout the gestational period in Wistar rats.

AIM OF THE STUDY

To evaluate the genotoxicity and the effect of treatment with dried extract of leaves of Azadirachta indica on maternal toxicity and fetal development.

MATERIALS AND METHODS

The dried extract of leaves of A. indica was obtained by spray drying after percolation of the plant material in 30% ethanol (w/w). The total flavonoids and rutin contents of the extract were determined by spectrophotometric method and HPLC-DAD, respectively. Pregnant Wistar rats (n = 40) were divided into four groups (n = 10/group): one control and three groups treated with dried extract of leaves of A. indica at doses of 300, 600 or 1200 mg/kg. Treatments were carried out from gestational day (GD) 0-20. During gestation, clinical signs of toxicity, weight gain, feed and water consumption of the dams were evaluated. On GD 21, rats were euthanized and cardiac blood was collected. Liver, kidneys, lung, heart, uterus, ovaries and bone marrow were collected. Reproductive performance parameters, histopathological analysis, biochemistry and genotoxicity were evaluated. Fetuses were evaluated for external morphology, skeletal and visceral changes.

RESULTS

The total flavonoid content of the extract ranged from 2.64 to 3.01%, and the rutin content was 1.07%. There was no change in body mass gain, food and water consumption between the evaluated groups. There was also no difference between the groups in terms of biochemical parameters, reproductive performance, histopathological analysis of the mother's organs and genotoxicity. Supernumerary ossification sites of the sternum were observed, and other skeletal and visceral alterations were not significant.

CONCLUSIONS

The treatment did not induce maternal toxicity, it was neither embryotoxic nor fetotoxic. The extract was not potentially genotoxic, and at a dose of 1200 mg/kg, it caused changes in the ossification of the sternum.

Double whammy: the genetic variants in CECR2 and high Hcy on the development of neural tube defects

Introduction: Neural tube defects (NTDs) are serious congenital malformations. The etiology of NTDs involves both genetic and environmental factors. Loss of CECR2 in mice has been shown to result in NTDs. Our previous study indicated that high homocysteine (HHcy) levels could further reduced the expression level of CECR2. This investigation aims to explore the genetic influence of the chromatin remodeling gene, CECR2, in humans and determine if HHcy can have a synergistic effect on protein expression. Methods: We conducted Next-Generation Sequencing (NGS) of the CECR2 gene in 373 NTD cases and 222 healthy controls, followed by functional assay application to select and evaluate CECR2 missense variants and subsequent Western blotting to identify protein expression levels. Results: From the analysis, we identified nine rare, NTD-specific mutations within the CECR2 gene. Significantly, four missense variants (p.E327V, p.T521S, p.G701R, and p.G868R) were selected via functional screening. The E9.5 mouse ectodermal stem cell line NE-4C, transfected with plasmids expressing p.E327V, p.T521S, p.G868R variants or a recombinant harboring all four (named as 4Mut), exhibited notable reductions in CECR2 protein expression. Furthermore, exposure to homocysteine thiolactone (HTL), an extremely reactive homocysteine metabolite, amplified the reduction in CECR2 expression, accompanied by a significant increase in the apoptotic molecule Caspase3 activity, a potential NTD inducer. Importantly, folic acid (FA) supplementation effectively counteracted the CECR2 expression decline induced by CECR2 mutation and HTL treatment, leading to reduced apoptosis. Discussion: Our observations underscore a synergistic relationship between HHcy and genetic variations in CECR2 concerning NTDs, thereby reinforcing the concept of gene-environment interaction phenomena in NTD etiology.

Case report: Sacral agenesis in two boxer dogs: clinical presentation, diagnostic investigations, and outcome

Two boxer dogs from the same litter were presented at 3 months of age for urinary and fecal incontinence. Both dogs had an abnormal tail consisting of a small stump, an atonic anal sphincter, and absent perineal reflex and sensation. Neurological evaluation was indicative of a lesion of the cauda equina or sacral spinal cord. Radiology and CT scan of the spine displayed similar findings in the two dogs that were indicative of sacral agenesis. Indeed, they had 6 lumbar vertebrae followed by a lumbosacral transitional vertebra, lacking a complete spinous process, and a hypoplastic vertebra carrying 2 hypoplastic sacral transverse processes as the only remnant of the sacral bone. Caudal vertebrae were absent in one of the dogs. On MRI, one dog had a dural sac occupying the entire spinal canal and ending in a subfascial fat structure. In the other dog, the dural sac finished in an extracanalar, subfascial, well-defined cystic structure, communicating with the subarachnoid space, and consistent with a meningocele. Sacral agenesis-that is the partial or complete absence of the sacral bones-is a neural tube defect occasionally reported in humans with spina bifida occulta. Sacral agenesis has been described in human and veterinary medicine in association with conditions such as caudal regression syndrome, perosomus elumbis, and Currarino syndrome. These neural tube defects are caused by genetic and/or environmental factors. Despite thorough genetic investigation, no candidate variants in genes with known functional impact on bone development or sacral development could be found in the affected dogs. To the best of the authors' knowledge, this is the first report describing similar sacral agenesis in two related boxer dogs.

Neural tube defects: Prevalence, mortality, and maternal characteristics in two departmental hospitals in the northwestern region of Nicaragua, 2006-2018

BACKGROUND

Congenital anomalies are the fifth most common cause of neonatal mortality in Nicaragua, and neural tube defects (NTDs) are the most common of all cases of lethality associated with a birth defect. Prevalence and mortality estimates are needed to propose effective intervention strategies that prevent NTDs over time.

METHODS

A cross-sectional study was carried out in northwestern Nicaragua from January 2006 to December 2018. All cases of NTDs (anencephaly, spina bifida, and encephalocele) were registered in hospital surveillance systems, and the medical histories of the mothers and newborns were reviewed. Prevalence was calculated by considering the number of live births and stillbirths older than 20 weeks of gestation with NTDs, divided by the total number of live births and stillbirths in each study year. Neonatal mortality rate (NMR) for NTD, and case fatality for spina bifida was calculated.

RESULTS

Two hundred fifty cases of NTDs were identified from 178,498 deliveries (177,316 live births and 1,182 stillbirths). The prevalence of NTDs during this time period was 14.01 (95% CI: 12.27-15.74) per 10,000 births. The prevalence of spina bifida (n = 140), anencephaly (n = 97), and encephalocele (n = 13) was 7.84, (95% CI: 6.54-9.14), 5.43 (95% CI: 4.30-6.45), and 0.73 (95% CI: 0.33-1.12) per 10,000 births, respectively. Mothers with fetus or newborns affected with NTDs did not use folic acid prior to conception, and 11% experienced periods of hyperthermia during the first trimester of pregnancy. NMR for NTDs was 0.55 per 1.000 livebirths. Case fatality for all NTDs and for spina bifida were 55% and 18%, respectively.

CONCLUSION

The prevalence and mortality of NTDs in the northwestern region of Nicaragua present peaks and troughs during the study period. Spina bifida was the most frequent type of NTD. We believe that these findings could be of use by health policy makers to strengthen the primary prevention of NTDs in the region through the monitoring of the food fortification policy and folic acid supplementation to women of childbearing age. Additional etiologic studies of NTDs should be considered to identify additional prevention measures.

Repair of spina bifida cystica: an institutional experience

Objective

Although most cases with spina bifida cystica could be closed by primary skin closure with or without undermining its edges, about 25% of patients have large defects not amenable for closure by these simple methods. We conducted this study to review our techniques in closing spina bifida cystica defects.

Methods

We retrospectively reviewed the data of consecutive 21 patients diagnosed with spina bifida cystica in our setting. According to the surface area of the defect, the approach was decided; primary closure for small defects (11 cases) and flap-based approach for large defects (10 patients).

Results

The age of the included pediatric patients ranged between 3 and 75 days. For the primary closure cases, a vertical incision was done in seven cases. For the flap-based group, bilateral rotation transposition flap was done for circular defects (7 cases) while elliptical ones were repaired via bilateral V–Y flap. Complete skin healing was achieved after two weeks (range 12–18 days) in most cases. Complications were as follows; for the primary closure group, cerebrospinal fluid leakage (18.18%%), partial wound dehiscence (18.18%) and superficial surgical site infection (9.09%). In the flap-based group, CSF leakage (20%), superficial surgical site infection (10%), and distal flap necrosis (30%) were detected. Reoperation for wound complication was needed only in one case in the flap-based group.

Conclusions

Flap-based procedures are recommended for patients with large spina bifida cystica defects because of less tissue dissection and low complication rates. Primary closure should be kept for small defects.

Advances in Fetal Surgical Repair of Open Spina Bifida

Spina bifida remains a common congenital anomaly of the central nervous system despite national fortification of foods with folic acid, with a prevalence of 2-4 per 10,000 live births. Prenatal screening for the early detection of this condition provides patients with the opportunity to consider various management options during pregnancy. Prenatal repair of open spina bifida, traditionally performed by the open maternal-fetal surgical approach through hysterotomy, has been shown to improve outcomes for the child, including decreased need for cerebrospinal fluid diversion surgery and improved lower neuromotor function. However, the open maternal-fetal surgical approach is associated with relatively increased risk for the patient and the overall pregnancy, as well as future pregnancies. Recent advances in minimally invasive prenatal repair of open spina bifida through fetoscopy have shown similar benefits for the child but relatively improved outcomes for the pregnant patient and future childbearing.

Ischemic myelomalacia and closed spinal dysraphism in multiple finishing swine

Ischemic myelomalacia secondary to fibrocartilaginous emboli (FCE) is an idiopathic disease in humans and animals. On the other hand, congenital spinal cord malformations result from neural tube defects in fetal development (ie, spinal dysraphism), with structural anomalies referred to collectively as myelodysplasia. Spinal dysraphisms are frequently accompanied by skin and vertebral abnormalities because of the embryogenic relationship. In this observational case study, we report the pathologic findings of 13, 18- to 24-weeks-old pigs from a large conventional operation that presented with acute paraparesis. Ischemic myelomalacia secondary to FCE was observed in 5 of 13 examined pigs. Congenital spinal cord malformations located between the caudal thoracic and sacral spinal cord were identified in 7 pigs, with structural abnormalities that ranged from diplomyelia/split cord malformation to segmental spinal dysgenesis (myelodysplasia) to caudal agenesis. Concurrent myelomalacia and congenital spinal cord malformations in the same or different sites were noted in 2 pigs. No spinal lesion was observed in 3 pigs. Although gross vertebral abnormalities were not observed herein, intervertebral instability due to minor defects in the articular facets, as well as other unidentified factors, is suspected to contribute high incidence of FCE. It is likely that these congenital malformations were previously underdiagnosed or are possibly new conditions associated with continuous inbreeding and genetic improvement in the modern swine industry.

Neural Tube Defects and Folate Deficiency: Is DNA Repair Defective?

Neural tube defects (NTDs) are complex congenital malformations resulting from failure of neural tube closure during embryogenesis, which is affected by the interaction of genetic and environmental factors. It is well known that folate deficiency increases the incidence of NTDs; however, the underlying mechanism remains unclear. Folate deficiency not only causes DNA hypomethylation, but also blocks the synthesis of 2'-deoxythymidine-5'-monophosphate (dTMP) and increases uracil misincorporation, resulting in genomic instabilities such as base mismatch, DNA breakage, and even chromosome aberration. DNA repair pathways are essential for ensuring normal DNA synthesis, genomic stability and integrity during embryonic neural development. Genomic instability or lack of DNA repair has been implicated in risk of development of NTDs. Here, we reviewed the relationship between folate deficiency, DNA repair pathways and NTDs so as to reveal the role and significance of DNA repair system in the pathogenesis of NTDs and better understand the pathogenesis of NTDs.

Parent/caregiver's role in nutrition, physical activity, and food access among children diagnosed with spina bifida

PURPOSE

This pilot study aimed to determine the parent/caregiver's role in nutrition/eating habits, physical activity behaviors, and food access among children diagnosed with spina bifida (SB).

METHODS

Parents/caregivers of children with SB were asked to participate at a single, outpatient SB clinic. Demographic, biomedical data, parent/caregiver nutrition knowledge, family nutrition and physical activity (FNPA), and food security survey scores were compared. Descriptive, regression, and correlational statistics were conducted for analysis via SPSS 29.

RESULTS

Of the 117 parents/caregivers surveyed, completed data suggested most were overweight/obese (average body mass index [BMI] of 30.63 kg/m2±8.40; n = 99) with an average nutrition knowledge score of 71% (17.83±3.33). As FNPA scores decreased, the patient/child's maximum BMI z scores increased (β= -0.043; confidence interval -0.079, -0.007; p = 0.020), suggesting the less active and/or less healthy eating habits, the higher body mass was noted for the child. Forty four percent of children (n = 99) were in the overweight/obese weight range based on maximum BMI z score.

CONCLUSION

These findings suggest there is a need for parental/caregiver nutrition education to assist children with SB with meal and activity planning to achieve optimal health.

Erken dönem civciv embriyo modelinde dimenhidrinatın nöral tüp gelişimi üzerine etkisi

Amaç: Bu çalışmada dimenhidrinat’ın erken dönem civciv embriyo modelinde nöral tüp gelişimi üzerindeki etkilerinin araştırılması amaçlanmıştır. Gereç ve Yöntem: Çalışmada 32 fertil, spesifik patojen olmayan yumurta kullanıldı. Tüm yumurtalar her bir grupta 8 adet olacak şekilde dört gruba ayrıldı. İnkübasyonun 28. saatinde deney gruplarına üç farklı dozda (0,7, 1,4, 2,1 mg/kg) dimenhidrinat ve kontrol grubuna serum fizyolojik enjekte edildi. İnkübasyonun 48. saatinde tüm embriyolar diseke edildi ve ışık mikroskobu altında histolojik olarak değerlendirildi. Bulgular: Kontrol, düşük, orta ve yüksek doz grubu embriyoları morfolojik olarak değerlendirildiğinde, kraniokaudal uzunluk ortalamaları sırasıyla; 8493,73±1342,90 µm, 5743,61±770,3 µm, 5572,62±315,32 µm, 5306,55±1135,99 µm, somit sayıları ortalamaları sırasıyla; 15,91±1,62, 15,38±1,19, 15,13±0,83, 10,63±5,15‘dir. Dimenhidrinat dozundaki artışa bağlı olarak kraniokaudal uzunluklarının ve somit sayılarının azaldığı tespit edildi. Dimenhidrinat doz artışına bağlı olarak nöral tüp açıklığının arttığı belirlendi . Sonuç: Bu çalışmada, erken dönem civciv embriyo modelinde dimenhidrinat uygulanan gruplarda doz artışına bağlı olarak nörogenezisin ve morfolojik gelişimin olumsuz etkilendiği görüldü.

Maternal morbidity under an absolute abortion ban: insights from a 6-year case series of fatal fetal malformations in El Salvador

BACKGROUND

A striking number of national and subnational governments that previously allowed legal abortion in cases of severe fetal anomaly have passed new legislation to explicitly remove these allowances. However, we know little about the maternal health implications of such restrictions.

OBJECTIVE

This study aimed to examine the health outcomes of pregnant individuals in El Salvador whose fetuses were diagnosed with a fatal congenital malformation and who were legally required to carry these nonviable pregnancies to term under the nation's absolute abortion ban.

STUDY DESIGN

We reviewed the charts of all 239 pregnancies with fetuses classified as having 1 of 18 congenital malformations typically considered to be incompatible with extrauterine life that were evaluated at the National Women's Hospital in El Salvador between January 1, 2013 and December 31, 2018. Because regional healthcare providers who identify pregnancy complications in El Salvador are instructed to refer those patients to the National Women's Hospital, our analysis captured the total population of lethal fetal malformations treated by the national public health system. We documented pregnant patients' socioeconomic characteristics, pregnancy-related complications, and the medical procedures used to mitigate complications.

RESULTS

Individuals who were required to carry pregnancies with severe fetal malformations to term (or until preterm labor began naturally) experienced high rates of maternal morbidity. More than half (54.9%) of pregnancies experienced at least 1 serious pregnancy-related health complication, whereas 47.9% underwent a physically-invasive medical procedure to manage complications, including cesarean deliveries, decompression amniocenteses, fetal head decompressions, and, in 1 case, a full hysterectomy. A total of 9% of patients opted to discontinue care after receiving the diagnosis of fatal fetal malformation. We also found striking variation in how physicians managed pregnancies with fatal fetal malformations, suggesting that different interpretations of the law lead to inequities in individual-level patient care.

CONCLUSION

Laws prohibiting abortions in cases of severe fetal malformation can increase risks to pregnant patients by requiring clinicians to subject healthy patients to a course of treatment that generates morbidity.

First-Trimester Influenza Infection Increases the Odds of Non-Chromosomal Birth Defects: A Systematic Review and Meta-Analysis

Viral infections during pregnancy raise several clinical challenges, including birth defects in the offspring. Thus, this systematic review and meta-analysis aims to prove and highlight the risk of birth defects after first-trimester maternal influenza infection. Our systematic search was performed on 21 November 2022. Studies that reported maternal influenza infection in the first trimester and non-chromosomal congenital abnormalities were considered eligible. We used odds ratios (OR) with 95% confidence intervals (CIs) to measure the effect size. Pooled ORs were calculated with a random effects model. Heterogeneity was measured with I² and Cochran's Q tests. We found that first-trimester maternal influenza was associated with increased odds of developing any type of birth defects (OR: 1.5, CI: 1.30-1.70). Moreover, newborns were more than twice as likely to be diagnosed with neural tube defects (OR: 2.48, CI: 1.95-3.14) or cleft lip and palate (OR: 2.48, CI: 1.87-3.28). We also found increased odds of developing congenital heart defects (OR: 1.63, CI: 1.27-2.09). In conclusion, influenza increases the odds of non-chromosomal birth defects in the first trimester. The aim of the present study was to estimate the risk of CAs in the offspring of mothers affected by first-trimester influenza infection.

BMP/Smad Pathway Is Involved in Lithium Carbonate-Induced Neural-Tube Defects in Mice and Neural Stem Cells

Neural-tube defects (NTDs) are one type of the most serious birth defects. Studies have shown that inositol deficiency is closely related to the occurrence of NTDs. Bone morphogenetic protein (BMP)-mediated Smad signaling pathways have been implicated in neurogenesis and neural-tube closure. However, the role of the BMP/Smad pathway in inositol-deficiency-induced NTDs remains unclear. Inositol-deficiency models in C57 mice and mouse neural stem cells (mNSCs) were induced with Li₂CO₃ treatment or inositol withdrawal. The role of the BMP/Smad pathway in the regulation of cell proliferation and the development of NTDs was determined utilizing qRT-PCR, HE staining, Western blot, immunostaining, MTT assay, EdU staining, and flow cytometry. The intraperitoneal injection of Li₂CO₃ at Embryonic Day 7.5 induced the occurrence of NTDs. The mRNA levels of Bmp2, Bmp4, Smad1, Smad5, Smad8 and Runx2, the phosphorylation of Smad1/5/8, and the nuclear translocation of Runx2 were significantly increased in NTD embryonic brain tissues and mNSCs exposed to Li₂CO₃ or an inositol-free medium, which were suppressed by BMP receptor selective inhibitor LDN-193189. The Li₂CO₃-induced phosphorylation of Smad1/5/8 was inhibited by inositol supplementation. Cell proliferation was significantly promoted by Li₂CO₃ exposure or the absence of inositol in mNSCs, which was reversed by LDN-193189. These results suggest that the activation of the BMP/Smad signaling pathway might play an important role in the development of NTDs induced by maternal Li₂CO₃ exposure via inositol deficiency.

Identifying key m6A-methylated lncRNAs and genes associated with neural tube defects via integrative MeRIP and RNA sequencing analyses

Objective: N6-methyladenosine (m6A) is a common post-transcriptional modification of messenger RNAs (mRNAs) and long non-coding RNAs (lncRNAs). However, m6A-modified lncRNAs are still largely unexplored. This study aimed to investigate differentially m6A-modified lncRNAs and genes involved in neural tube defect (NTD) development. Methods: Pregnant Kunming mice (9-10 weeks of age) were treated with retinoic acid to construct NTD models. m6A levels and methyltransferase-like 3 (METTL3) expression were evaluated in brain tissues of the NTD models. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) were performed on the NovaSeq platform and Illumina HiSeq 2,500 platform, respectively. Differentially m6A-methylated differentially expressed lncRNAs (DElncRNAs) and differentially expressed genes (DEGs) were identified, followed by GO biological process and KEGG pathway functional enrichment analyses. Expression levels of several DElncRNAs and DEGs were evaluated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for validation. Results: m6A levels and METTL3 expression levels were significantly lower in the brain tissues of the NTD mouse model than in controls. By integrating MeRIP-seq and RNA-seq data, 13 differentially m6A-methylated DElncRNAs and 170 differentially m6A-methylated DEGs were identified. They were significantly enriched in the Hippo signaling pathway and mannose-type O-glycan biosynthesis. The qRT-PCR results confirmed the decreased expression levels of lncRNAs, such as Mir100hg, Gm19265, Gm10544, and Malat1, and genes, such as Zfp236, Erc2, and Hmg20a, in the NTD group. Conclusion: METTL3-mediated m6A modifications may be involved in NTD development. In particular, decreased expression levels of Mir100hg, Gm19265, Gm10544, Malat1, Zfp236, Erc2, and Hmg20a may contribute to the development of NTD.

Prenatal diagnosis and pregnancy outcome of major structural anomalies detectable in the first trimester: A population-based cohort study in the Netherlands

BACKGROUND

Prenatal diagnosis of several major congenital anomalies can be achieved in the first trimester of pregnancy.

OBJECTIVE

This study investigates the timing of diagnosis and pregnancy outcome of foetuses and neonates with selected structural anomalies in the Northern Netherlands over a 10-year period when the prenatal screening programme changed significantly, but no first-trimester anatomical screening was implemented.

METHODS

We performed a population-based retrospective cohort study with data from the EUROCAT Northern Netherlands database on pregnancies with delivery or termination of pregnancy for fetal anomaly (TOPFA) date between 2010 and 2019. The analysis was restricted to anomalies potentially detectable in the first trimester of pregnancy in at least 50% of cases, based on previously published data. These included: anencephaly, encephalocele, spina bifida, holoprosencephaly, tricuspid/pulmonary valve atresia, hypoplastic left heart, abdominal wall and limb reduction defects, lethal skeletal dysplasia, megacystis, multiple congenital anomalies. The primary outcome was the timing of diagnosis of each structural anomaly. Information on additional investigations, genetic testing and pregnancy outcome (live birth, TOPFA and foetal/neonatal death) was also collected.

RESULTS

A total of 478 foetuses were included; 95.0% (n = 454) of anomalies were detected prenatally and 5.0% (n = 24) postpartum. Among the prenatally detected cases, 31% (n = 141) were diagnosed before 14 weeks of gestation, 65.6% (n = 298) between 14-22 weeks and 3.3% (n = 15) after 22 weeks. Prenatal genetic testing was performed in 80.4% (n = 365) of cases with prenatally diagnosed anomalies, and the results were abnormal in 26% (n = 95). Twenty-one% (n = 102) of pregnancies resulted in live births and 62.8% (n = 300) in TOPFA. Spontaneous death occurred in 15.9% (n = 76) of cases: in-utero (6.1%, n = 29), at delivery (7.7%, n = 37) or in neonatal life (2.1%, n = 10).

CONCLUSION

Major structural anomalies amenable to early diagnosis in the first trimester of pregnancy are mostly diagnosed during the second trimester in the absence of a regulated first-trimester anatomical screening programme in the Netherlands and are associated with TOPFA and spontaneous death, especially in cases with underlying genetic anomalies.

Diabetic Embryopathies

Diabetic embryopathy is defined as congenital anomalies that are linked to maternal diabetes. The association between diabetes and fetal, neonatal, and long-term complications is well-established. These complications include organ or structural maldevelopment, fetal growth abnormalities, and learning/psychiatric comorbidities. Recent studies have elucidated the pathophysiology behind these conditions and outlined new management approaches. Caudal regression syndrome, also known as sacral agenesis, is a well-known but less described complication of maternal diabetes. The purpose of this review is to summarize existing research on common neonatal morbidities in infants of mothers with diabetes with a focus on caudal regression syndrome and its long-term associations.

Folate deficiency disturbs PEG10 methylation modifications in human spina bifida

BACKGROUND

Paternally expressed gene 10 (PEG10) is believed to be a key imprinted gene involved in placenta formation. However, its role in human folate-related spina bifida (SB) remains unclear.

METHODS

The methylation status of the germline differentially methylated region (gDMR) in the PEG10/sarcoglycan epsilon (SGCE) imprinted cluster was compared between SB patients and control samples. Moreover, the influence of ectopic PEG10 expression on apoptosis was assessed to explore the underlying mechanisms related to folate deficiency-induced aberrant gDMR methylation in SB.

RESULTS

The case group exhibited a significant increase in the methylation level of the gDMR and a marked reduction in the mRNA and protein expression of PEG10 compared with the control group. A prominent negative correlation was found between the folate level in brain tissue and gDMR methylation status (r = -0.62, P = 0.001). A cell model treated with a demethylating agent showed a significant elevation of PEG10 transcription level, as well as other imprinted genes in this cluster. In addition, the inhibition of PEG10 was found to be accompanied by aberrant activation of apoptosis in SB.

CONCLUSIONS

Our findings suggest that disturbed gDMR methylation of the PEG10/SGCE cluster due to folate deficiency is involved in SB through aberrant activation of apoptosis.

IMPACT

Disturbed genomic imprinting has been verified to be involved in neural tube defects (NTDs). However, little is known about the effect of ectopic expression of imprinted gene PEG10 on human NTDs. Aberrant methylation status of the germline differentially methylated region (gDMR) of PEG10/SGCE cluster due to folate deficiency has been found to result in the inhibition of PEG10 and has a marked association with an increased occurrence of spina bifida. Inhibited expression of PEG10 partly is found to be related to the abnormal activation of apoptosis in spina bifida.