Associated anomalies with neural tube defects in fetal autopsies

Congenital anomalies of kidney and urinary tract (CAKUT) and associated extra-renal anomalies in fetal autopsies

OBJECTIVES AND BACKGROUND

According to studies, 1% of all pregnancies have an abnormality, with 20-30% of those affecting the genitourinary system. Congenital abnormalities of the kidney and urinary tract (CAKUT) is one of the primary causes of perinatal and neonatal mortality in children. Many extra-renal congenital illnesses accompany these defects, affecting the patient's prognosis. This study aims to determine the subtypes, frequency, and extra-renal defects associated with congenital anomalies of the urinary system, which is the major cause of mortality in fetal and infant autopsies throughout the perinatal and neonatal eras. We believe that our study will contribute to the literature because few autopsy investigations can give this data.

MATERIALS AND METHODS

The study included 110 fetal autopsies between January 1997 and May 2019. 10% were newborns under the age of one year, and 90% were fetus autopsies.

RESULTS

Males accounted for 67.3% of the cases, while females accounted for 35 (31.8%) (the gender of one case could not be determined). Renal dysplasia was the most frequent CAKUT, with a rate of 22.73%, followed by renal agenesis, with a rate of 20.0%. Eighty-four cases (76.3%) showed disease in at least one other organ system. Musculoskeletal system (MSS) abnormalities were the most common associated system anomaly, with one or more MSS anomalies (34.55%) detected in 38 cases.

CONCLUSION

Finally, we want to underline that CAKUT and its associated anomalies are not uncommon. Prenatal imaging, genetic investigation, and/or postmortem examination should all be used to screen for CAKUT. This information is helpful for the mother's future pregnancy management and parental genetic counseling.

Cerebral Abnormalities in Spina Bifida: A Neuropathological Study

INTRODUCTION

Spina bifida (SB) is the most common neural tube defect in humans. Here, we analyzed systematically the neuropathological findings of the brain in SB cases.

METHODS

79 cases with SB aperta (SBA) and 6 cases with SB occulta (SBO) autopsied at the Charité Neuropathology from 1974 to 2000 were re-evaluated retrospectively. For this, case files and spinal cord as well as brain sections were studied.

RESULTS

While no brain malformations were detected in SBO cases, 95% of SBA cases had brain malformations. Main brain anomalies identified were hydrocephalus (71%), Chiari II malformation (36%), heterotopia (34%), other cerebellar anomalies (36%), gyrification defects (33%), and ependymal denudation (29%). Hydrocephalus was observed as early as gestational week 17 and was highly associated to Chiari II and ependymal denudation. In 55% SBA was accompanied by further anomalies not primarily affecting the CNS.

CONCLUSION

We confirm using neuropathologic methods brain malformations in most SBA but none in SBO cases. In addition to our previous radiologic study, we now demonstrate the high prevalence of cerebellar malformations and cerebral heterotopias in SBA. The early detection of hydrocephalus and Chiari II malformation in fetuses raises the question whether these arise parallel rather than in strict temporal sequence.

Early prenatal diagnosis of an atypical phenotype of sacral spina bifida

Neural tube defects (NTDs) occur during embryogenesis, specifically during the fifth or sixth week of gestation, and are described as aberrant neural tube closing. The defect may alter the normal development of the vertebrae, spinal cord, cranium, or brain. The present study describes the case of a 41-year-old pregnant woman with fetal sacral meningocele, no associated pathologies, no family history of neural tube defects, a pregnancy under folate supplementation with the aim of highlighting the importance of ultrasound in diagnosing neural tube defects. The ultrasonographic diagnosis was not clear from the beginning. In our case, the differential diagnosis of meningocele was made with the cystic compound of a sacrococcygeal teratoma, which represents one of the most common congenital tumors in newborns. The particularity of this case was that a neural tube defect occurred despite the prophylactic administration of folic acid during pregnancy, which represents a well-documented protection against neural tube defects in fetuses.

Incidence of neural tube defects and their risk factors within a cohort of Moroccan newborn infants

Background

Neural tube defects (NTDs) are a group of birth defects that result from a partial or complete failure of the neural tube to close during embryogenesis. Their prevalence varies between 0.5 to 2 per 1000 births in countries without folic acid supplementation. The aim of our study is to assess the NTDs incidence and describe the risk factors within Moroccan newborn infants.

Method

This is a descriptive study over a period of 5 and a half years including all births at “Les Orangers” Maternity and Reproductive Health Hospital of Rabat with notification of NTD cases, whether isolated or combined with other anomalies. Data were reported on pre-established sheets and on the teratovigilance registry. Statistical analysis was performed with SPSS version 18 statistical software.

Results

During the study period, 43,923 births were recorded including 44 cases of neural tube defects, an incidence rate of 1 per 1000 births, with a female predominance; sex ratio = 0.8. These defects included anencephaly (50%), spina bifida (38.6%) and encephalocele (11.4%). The risk factors detected during this study include consanguinity (34%), consumption of fenugreek or other plants (36%), diabetes (4.5%) and medication (2.2%). A family history of malformation was reported in 6.8% of cases and among siblings in 4.5% of cases. The average maternal age was 30.38 ± 6.88 and the average gestational age was 36.80 ± 5.11. A quarter of mothers did not benefit from any medical monitoring during pregnancy while 59% did not take folic acid supplementation during the first trimester of pregnancy and none of them took B9 vitamin during the periconceptional period. The antenatal diagnosis was performed in 63% of cases. The mortality rate was 3.8 per 10,000 and 16% of cases evolved positively.

Conclusion

NTDs require high intensity and multidisciplinary care which stresses the importance, in our context, of strengthening and optimizing acid folic supplementation strategies during the periconceptional period.

Systematic Classification of Spina Bifida

Spina bifida (SB) is an umbrella term for multiple conditions characterized by misclosure of vertebral arches. Neuropathologic findings in SB cases are often reported with imprecise and overlapping terminology. In view of the increasing identification of SB-associated genes and pathomechanisms, the precise description of SB subtypes is highly important. In particular, the term "myelomeningocele" is applied to various and divergent SB subtypes. We reevaluated 90 cases with SB (58 prenatal; 32 postnatal). The most frequent SB phenotype in our cohort was myeloschisis, which is characterized by an open neural plate with exposed ependyma (n = 28; 31.1%). An open neural plate was initially described in only in two-thirds of the myeloschisis cases. An additional 21 cases (23.3%) had myelomeningocele; 2 cases (2.2%) had a meningocele; and 21 cases (23.3%) had an unspecified SB aperta (SBA) subtype. Overall, the SB phenotype was corrected in about one-third of the cases. Our findings highlight that "myelomeningocele" and "SB aperta" cannot be used as synonymous terms and that myeloschisis is an underreported SB phenotype. Based on our findings and a review of literature we propose a classification of SB subtypes in SB occulta and the 3 SBA subtypes, meningocele, myelomeningocele, and myeloschisis.

Fetal spina bifida: What we tell the parents

Worldwide, about 150 000 infants are born with spina bifida yearly, making this condition one of the most common fetal central nervous system anomalies compatible with life. Over the last decade, major changes have been introduced in the prenatal diagnosis and management of spina bifida. In this review, we provide a brief summary of the current management of fetal spina bifida and present essential information that should be provided to expecting parents when their fetus has been diagnosed with spina bifida. This information is focused around common parental questions, as encountered in our typical clinical practice, to facilitate knowledge translation.

Incidence of Congenital Spinal Abnormalities Among Pediatric Patients and Their Association With Scoliosis and Systemic Anomalies

BACKGROUND

Congenital abnormalities when present, according to VACTERL theory, occur nonrandomly with other congenital anomalies. This study estimates the prevalence of congenital spinal anomalies, and their concurrence with other systemic anomalies.

METHODS

A retrospective cohort analysis on Health care Cost and Utilization Project's Kids Inpatient Database (KID), years 2000, 2003, 2006, 2009 was performed. ICD-9 coding identified congenital anomalies of the spine and other body systems.

OUTCOME MEASURES

Overall incidence of congenital spinal abnormalities in pediatric patients, and the concurrence of spinal anomaly diagnoses with other organ system anomalies. Frequencies of congenital spine anomalies were estimated using KID hospital-and-year-adjusted weights. Poisson distribution in contingency tables tabulated concurrence of other congenital anomalies, grouped by body system.

RESULTS

Of 12,039,432 patients, rates per 100,000 cases were: 9.1 hemivertebra, 4.3 Klippel-Fiel, 56.3 Chiari malformation, 52.6 tethered cord, 83.4 spina bifida, 1.2 absence of vertebra, and 6.2 diastematomyelia. Diastematomyelia had the highest concurrence of other anomalies: 70.1% of diastematomyelia patients had at least one other congenital anomaly. Next, 63.2% of hemivertebra, and 35.2% of Klippel-Fiel patients had concurrent anomalies. Of the other systems deformities cooccuring, cardiac system had the highest concurrent incidence (6.5% overall). In light of VACTERL's definition of a patient being diagnosed with at least 3 VACTERL anomalies, hemivertebra patients had the highest cooccurrence of ≥3 anomalies (31.3%). With detailed analysis of hemivertebra patients, secundum ASD (14.49%), atresia of large intestine (10.2%), renal agenesis (7.43%) frequently cooccured.

CONCLUSIONS

Congenital abnormalities of the spine are associated with serious systemic anomalies that may have delayed presentations. These patients continue to be at a very high, and maybe higher than previously thought, risk for comorbidities that can cause devastating perioperative complications if not detected preoperatively, and full MRI workups should be considered in all patients with spinal abnormalities.

LEVEL OF EVIDENCE

Level III.

Neural Tube Defects in Embryonic Life: Lessons Learned From 340 Early Pregnancy Failures

OBJECTIVES

The aim of this study was to evaluate the feasibility of sonographic assessment of the embryonic/fetal neural tube in nonviable pregnancies and to determine the defect incidence.

METHODS

Prospective analysis of transvaginally acquired 3-dimensional (3D) multiplanar and 3D surface-rendered volume sets of 340 cases of missed abortion between March 2010 and September 2015 was performed. Data regarding karyotype and postmortem examination as well as demographic features and the outcomes of subsequent pregnancies were evaluated.

RESULTS

In 223 cases, an embryo/fetus was detected and considered suitable for further evaluation: in 37 of 223 (16.6%) embryos/fetuses, a neural tube defect was present: 27 of 37 cephaloceles, 5 of 37 anencephalies/exencepahlies, 3 of 37 spina bifidas, 1 of 37 caudal regression syndrome, and 1 of 37 iniencephaly. Additional alterations were not observed. In 7 of 37 cases karyotyping was carried out and showed no aneuploidy. Eight subsequent pregnancies had a favorable outcome, with 1 ending in an intrauterine fetal death during the 22nd week of gestation. Maternal folic acid supplementation was provided for all subsequent pregnancies. No neural tube defects occurred.

CONCLUSIONS

Sonographic 3D evaluation of complete neural tube closure in embryonic/fetal demise is technically feasible and can be achieved in embryos with a crown-rump length greater than 8 mm. In 26 of 37 cases a defective closure site could be allocated to high-risk areas known for early embryonic demise. Regardless of the etiology of different neural tube defects, high-dose folic acid prophylaxis must be recommended in all cases. Sonographic evaluation of the neural tube, including 3D surface-rendered images, should be offered to every woman with a missed abortion because of the impact on subsequent pregnancies.

Perinatal Diagnostic Approach to Fetal Skeletal Dysplasias: Six Years Experience of a Tertiary Center

Skeletal dysplasias (SDs) constitute a group of heterogeneous disorders affecting growth morphology of the chondro-osseous tissues. Prenatal diagnosis of SD is a considerable clinical challenge due to phenotypic variability. We performed a retrospective analysis of the fetal autopsies series conducted between January 2006 and December 2012 at our center. SD was detected in 54 (10%) out of 542 fetal autopsy cases which included; 11.1% thanatophoric dysplasia (n = 6), 7.4% achondroplasia (n = 4), 3.7% osteogenesis imperfect (n = 2), 1.9% Jarcho-Levin Syndrome (n = 1), 1.9% arthrogryposis (n = 1), 1.9% Dyggve-Melchior-Clausen syndrome (n = 1), 72.1% of dysostosis cases (n = 39). All SD cases were diagnosed by ultrasonography. In 20 of the cases, amniocentesis was performed, 4 cases underwent molecular genetic analyses. Antenatal identification of dysplasia is important in the management of pregnancy and in genetic counseling. Our data analysis showed that SD is usually detected clinically after the 20th gestational week. Genetic analyses for SD may provide early diagnosis and management.