Risk of meningomyelocele mediated by the common 22q11.2 deletion

Meningomyelocele is one of the most severe forms of neural tube defects (NTDs) and the most frequent structural birth defect of the central nervous system. We assembled the Spina Bifida Sequencing Consortium to identify causes. Exome and genome sequencing of 715 parent-offspring trios identified six patients with chromosomal 22q11.2 deletions, suggesting a 23-fold increased risk compared with the general population. Furthermore, analysis of a separate 22q11.2 deletion cohort suggested a 12- to 15-fold increased NTD risk of meningomyelocele. The loss of Crkl, one of several neural tube-expressed genes within the minimal deletion interval, was sufficient to replicate NTDs in mice, where both penetrance and expressivity were exacerbated by maternal folate deficiency. Thus, the common 22q11.2 deletion confers substantial meningomyelocele risk, which is partially alleviated by folate supplementation.

Feeding dysfunction in NICU patients with cramped synchronized movements

Patients admitted to the neonatal intensive care unit (NICU) have higher association for neurodevelopment deficits, specifically cerebral palsy (CP). We identified patients with risk for CP using abnormal Pretchl's General Movement Assessment (GMA) and sub-category of cramped synchronized movements (CSM) and reported their feeding outcomes at discharge. Over 75 % of these patients required either nasogastric (NGT) or gastrostomy tube (GT) at discharge. Of these, 57 % weaned off their NGT or GT at home and 43 % of patients still needed a GT one year after discharge. Of those that could not wean off their NGT or GT, these patients had longer hospital stay, took lower percentage by mouth, and an older post-menstrual age at discharge. We did not find a difference in NGT or GT use between patients with IVH, ELBW, nor between their birthweight or gestation age at birth. This study provides further clinical characteristics in NICU patients who have higher risk of CP, and supports the need for skilled feeding therapy and resources both during and after NICU admission.

Analysis of an Expanded Targeted Early Cytomegalovirus Testing Program

OBJECTIVE

Determine the detection rate from an expanded targeted early cytomegalovirus (CMV) testing program implemented from a large healthcare system (Intermountain Healthcare, IHC).

STUDY DESIGN

Retrospective review.

SETTING

Tertiary medical center.

METHODS

An electronic system was modified to include indications for testing whenever a provider placed an order for CMV testing. A retrospective analysis of this database was performed.

RESULTS

From March 1, 2021 to August 31, 2022, there were 3450 (8.8%) patients who underwent CMV testing out of 39,245 total live births within the IHC system. Since the formal implementation of this program in 2019, annual CMV testing has increased almost 10-fold: 2668 CMV tests were performed in 2021 compared to 289 CMV tests in 2015. The most frequent indication for congenital CMV (cCMV) testing was small for gestational age (SGA) (68.2%), followed by macrocephaly (13.5%), an abnormal hearing test (5.0%), and microcephaly (4.4%). Fourteen cCMV-infected infants were diagnosed all of them meeting the criteria for symptomatic cCMV. The most common indication resulting in a positive diagnosis was those who presented with SGA (n = 10 patients). The positivity rate would result in a prevalence of 35.7 symptomatic cCMV cases diagnosed per 100,000 live births, numbers comparable to those expected for universal cCMV screening.

CONCLUSION

An expanded targeted early cCMV testing program may improve detection rates of symptomatic cCMV cases and should be considered as a feasible alternative approach to universal or hearing-targeted early CMV testing.

Rapid genome sequencing identifies a novel de novo SNAP25 variant for neonatal congenital myasthenic syndrome

Congenital myasthenic syndrome (CMS) is a group of 32 disorders involving genetic dysfunction at the neuromuscular junction resulting in skeletal muscle weakness that worsens with physical activity. Precise diagnosis and molecular subtype identification are critical for treatment as medication for one subtype may exacerbate disease in another (Engel et al., Lancet Neurol 14: 420 [2015]; Finsterer, Orphanet J Rare Dis 14: 57 [2019]; Prior and Ghosh, J Child Neurol 36: 610 [2021]). The SNAP25-related CMS subtype (congenital myasthenic syndrome 18, CMS18; MIM #616330) is a rare disorder characterized by muscle fatigability, delayed psychomotor development, and ataxia. Herein, we performed rapid whole-genome sequencing (rWGS) on a critically ill newborn leading to the discovery of an unreported pathogenic de novo SNAP25 c.529C > T; p.Gln177Ter variant. In this report, we present a novel case of CMS18 with complex neonatal consequence. This discovery offers unique insight into the extent of phenotypic severity in CMS18, expands the reported SNAP25 variant phenotype, and paves a foundation for personalized management for CMS18.

Genetic Testing to Inform Epilepsy Treatment Management From an International Study of Clinical Practice

Importance

It is currently unknown how often and in which ways a genetic diagnosis given to a patient with epilepsy is associated with clinical management and outcomes.

Objective

To evaluate how genetic diagnoses in patients with epilepsy are associated with clinical management and outcomes.

Design, Setting, and Participants

This was a retrospective cross-sectional study of patients referred for multigene panel testing between March 18, 2016, and August 3, 2020, with outcomes reported between May and November 2020. The study setting included a commercial genetic testing laboratory and multicenter clinical practices. Patients with epilepsy, regardless of sociodemographic features, who received a pathogenic/likely pathogenic (P/LP) variant were included in the study. Case report forms were completed by all health care professionals.

Exposures

Genetic test results.

Main Outcomes and Measures

Clinical management changes after a genetic diagnosis (ie, 1 P/LP variant in autosomal dominant and X-linked diseases; 2 P/LP variants in autosomal recessive diseases) and subsequent patient outcomes as reported by health care professionals on case report forms.

Results

Among 418 patients, median (IQR) age at the time of testing was 4 (1-10) years, with an age range of 0 to 52 years, and 53.8% (n = 225) were female individuals. The mean (SD) time from a genetic test order to case report form completion was 595 (368) days (range, 27-1673 days). A genetic diagnosis was associated with changes in clinical management for 208 patients (49.8%) and usually (81.7% of the time) within 3 months of receiving the result. The most common clinical management changes were the addition of a new medication (78 [21.7%]), the initiation of medication (51 [14.2%]), the referral of a patient to a specialist (48 [13.4%]), vigilance for subclinical or extraneurological disease features (46 [12.8%]), and the cessation of a medication (42 [11.7%]). Among 167 patients with follow-up clinical information available (mean [SD] time, 584 [365] days), 125 (74.9%) reported positive outcomes, 108 (64.7%) reported reduction or elimination of seizures, 37 (22.2%) had decreases in the severity of other clinical signs, and 11 (6.6%) had reduced medication adverse effects. A few patients reported worsening of outcomes, including a decline in their condition (20 [12.0%]), increased seizure frequency (6 [3.6%]), and adverse medication effects (3 [1.8%]). No clinical management changes were reported for 178 patients (42.6%).

Conclusions and Relevance

Results of this cross-sectional study suggest that genetic testing of individuals with epilepsy may be materially associated with clinical decision-making and improved patient outcomes.

Child Neurology: Case Report of Lambl Excrescences in a Pediatric Patient With Multifocal Strokes

Lambl excrescences are fibrinous connective tissue strands found predominantly on left-sided cardiac valves. These valvular strands are typically benign, but have been implicated as a potential etiology of embolic strokes in adult patients. The significance of Lambl excrescences in pediatric stroke cases is unclear and not previously reported in the literature. In this study, we describe a 10-year-old boy who presented with acute-onset right-sided hemiplegia, found to have multifocal embolic strokes of various ages. Extensive stroke workup was unrevealing, aside from the presence of small, filamentous, strand-like densities associated with the mitral and aortic valves noted on a transesophageal echocardiogram consistent with Lambl excrescences. In this case report, we review Lambl excrescences and their significance in acute stroke and management options for the prevention of future ischemia in these patients.

Treatment of Neonatal Seizures: Comparison of Treatment Pathways From 11 Neonatal Intensive Care Units

OBJECTIVE

Seizures are a common neonatal neurologic emergency. Many centers have developed pathways to optimize management. We evaluated neonatal seizure management pathways at level IV neonatal intensive care units (NICUs) in the United States to highlight areas of consensus and describe aspects of variability.

METHODS

We conducted a descriptive analysis of 11 neonatal seizure management pathways from level IV NICUs that specialize in neonatal neurocritical care including guidelines for electroencephalography (EEG) monitoring, antiseizure medication (ASM) choice, timing, and dose.

RESULTS

Study center NICUs had a median of 70 beds (interquartile range: 52-96). All sites had 24/7 conventional EEG initiation, monitoring, and review capability. Management pathways uniformly included prompt EEG confirmation of seizures. Most pathways included a provision for intravenous benzodiazepine administration if either EEG or loading of ASM was delayed. Phenobarbital 20 mg/kg IV was the first-line ASM in all pathways. Pathways included either fosphenytoin or levetiracetam as the second-line ASM with variable dosing. Third-line ASMs were most commonly fosphenytoin or levetiracetam, with alternatives including topiramate or lacosamide. All pathways provided escalation to continuous midazolam infusion with variable dosing for seizures refractory to initial medication trials. Three pathways also included lidocaine infusion. Nine pathways discussed ASM discontinuation after resolution of acute symptomatic seizures with variable timing.

CONCLUSIONS

Despite a paucity of data from controlled trials regarding optimal neonatal seizure management, there are areas of broad agreement among institutional pathways. Areas of substantial heterogeneity that require further research include optimal second-line ASM, dosage, and timing of ASM discontinuation.

Dexmedetomidine Use in Infants Undergoing Cooling Due to Neonatal Encephalopathy (DICE Trial): A Randomized Controlled Trial: Background, Aims and Study Protocol

Background: Neonatal hypoxia-ischemia encephalopathy (HIE) is the leading cause of neonatal death and poor neurodevelopmental outcomes worldwide. Therapeutic hypothermia (TH), while beneficial, still leaves many HIE treated infants with lifelong disabilities. Furthermore, infants undergoing TH often require treatment for pain and agitation which may lead to further brain injury. For instance, morphine use in animal models has been shown to induce neuronal apoptosis. Dexmedetomidine is a potent α₂-adrenergic receptor agonist that may be a better alternative to morphine for newborns with HIE treated with TH. Dexmedetomidine provides sedation, analgesia, and prevents shivering but does not suppress ventilation. Importantly, there is increasing evidence that dexmedetomidine has neuroprotective properties. Even though there are limited data on pharmacokinetics (PK), safety and efficacy of dexmedetomidine in infants with HIE, it has been increasingly administered in many centers.

Objectives: To review the current approach to treatment of pain, sedation and shivering in infants with HIE undergoing TH, and to describe a new phase II safety and pharmacokinetics randomized controlled trial that proposes the use of dexmedetomidine vs. morphine in this population.

Methods: This article presents an overview of the current management of pain and sedation in critically ill infants diagnosed with HIE and undergoing TH for 72 h. The article describes the design and methodology of a randomized, controlled, unmasked multicenter trial of dexmedetomidine vs. morphine administration enrolling 50 (25 per arm) neonates ≥36 weeks of gestation with moderate or severe HIE undergoing TH and that require pain/sedation treatment.

Results and Conclusions: Dexmedetomidine may be a better alternative to morphine for the treatment of pain and sedation in newborns with HIE treated with TH. There is increasing evidence that dexmedetomidine has neuroprotective properties in several preclinical studies of injury models including ischemia-reperfusion, inflammation, and traumatic brain injury as well as adult clinical trials of brain trauma. The Dexmedetomidine Use in Infants undergoing Cooling due to Neonatal Encephalopathy (DICE) trial will evaluate whether administration of dexmedetomidine vs. morphine is safe, establish dexmedetomidine optimal dosing by collecting opportunistic PK data, and obtain preliminary neurodevelopmental data to inform a large Phase III efficacy trial with long term neurodevelopment impairment as the primary outcome.

Neurological and clinical outcomes in infants and children with a fetal diagnosis of asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum

OBJECTIVE

Advances in prenatal imaging have facilitated improvements in the fetal diagnosis of congenital anomalies. Asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum (AVID) is a constellation of congenital anomalies reported in fetal imaging. However, few data are available regarding postnatal outcomes of infants and children with a fetal diagnosis of AVID. The authors sought to report the neurodevelopmental outcomes of patients diagnosed with AVID before birth at a single institution.

METHODS

An institutional fetal imaging database was queried to identify cases with ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum over a 10-year study period from 2000 to 2019. Overall, 41 maternal-infant dyads who met imaging criteria for AVID were identified; medical records were reviewed for prenatal variables including gestational age at birth, perinatal complications including fetal demise, and postnatal variables including demographics, mortality, hydrocephalus diagnosis and management, epilepsy, and neurodevelopmental outcomes at 2 years or the last follow-up.

RESULTS

Among 41 patients, 25 (61%) were male. A slight majority of patients (55%) were born before 36 weeks of gestational age, and 27 patients (68%) were delivered via cesarean section because their head size precluded vaginal delivery. There were 8 incidences of fetal demise, 1 pregnancy was terminated, and 32 patients were born alive. Neonatal or early infant death occurred in 5 patients. Two children died during follow-up after the neonatal period (ages 7 months and 7 years). Twenty-six children survived to at least the 2-year follow-up, all of whom required treatment for hydrocephalus. Of those 26 children, 12 (46%) had a diagnosis of epilepsy, 14 (54%) could sit independently, 4 (16%) were in mainstream school, 16 (62%) had expressive language, and 7 (28%) had near-normal development without seizures.

CONCLUSIONS

Among 41 maternal-fetal dyads with AVID, a majority of children survived to the 2-year follow-up, although all developed hydrocephalus. Many continued to have seizures, but expressive language use, attendance at mainstream school, and near-normal development without seizures were not infrequent. These data are critical for prenatal counseling and to establish the natural history of a diagnosis with limited outcome data.

A comparison of the accuracy of fetal MRI and prenatal ultrasonography at predicting lesion level and perinatal motor outcome in patients with myelomeningocele

OBJECTIVE

Prenatal imaging has several critical roles in the diagnosis and management of myelomeningocele, including specific family counseling and the selection of fetal surgery or postnatal repair. In this study, the authors compared the accuracy of fetal MRI and prenatal ultrasonography (US) in predicting the spinal lesion level and assessed the correlation between imaging findings and motor function as independently evaluated by a physical therapist (PT) after birth.

METHODS

A retrospective review of demographic and clinical data was performed to identify children who had been treated with postnatal myelomeningocele closure at a single institution between March 2013 and December 2018. Patients were eligible for inclusion if they had all of the following: prenatal US identifying the neural tube defect level, fetal MRI identifying the neural tube defect level, and postoperative PT evaluation identifying the motor deficit level. Statistical analysis was performed using Cohen's kappa coefficient to compare the US- and MRI-demonstrated lesion level and correlate these findings with the motor level assigned postnatally by a PT via manual muscle testing.

RESULTS

Thirty-four patients met the inclusion criteria. The mean gestational age at US was 23.0 ± 4.7 weeks, whereas the mean gestational age at MRI was 24.0 ± 4.1 weeks. The mean time from surgery to the PT evaluation was 2.9 ± 1.9 days. Prenatal US and MRI were in agreement within one spinal level in 74% of cases (25/34, k = 0.43). When comparing the US-demonstrated spinal level with the PT-assigned motor level, the two were in agreement within one level in 65% of cases (22/34, k = 0.40). When comparing MRI-demonstrated spinal level with the PT motor level, the two were in agreement within one level in 59% of cases (20/34, k = 0.37). MRI and US were within two spinal levels of the PT evaluation in 79.4% and 85.3% of cases, respectively. MRI and US agreed within two levels in 97.1% of cases. Prenatal US and MRI were equivalent when comparing the difference between the imaged level and the postnatal motor deficit level (mean level difference: 1.12 ± 1.16 vs 1.17 ± 1.11, p = 0.86).

CONCLUSIONS

Prenatal US and MRI equivalently predicted the postnatal motor deficit level in children with myelomeningocele. These data may be valuable in prenatal prognostication.

Network Implementation of Guideline for Early Detection Decreases Age at Cerebral Palsy Diagnosis

BACKGROUND AND OBJECTIVES

Early diagnosis of cerebral palsy (CP) is critical in obtaining evidence-based interventions when plasticity is greatest. In 2017, international guidelines for early detection of CP were published on the basis of a systematic review of evidence. Our study aim was to reduce the age at CP diagnosis throughout a network of 5 diverse US high-risk infant follow-up programs through consistent implementation of these guidelines.

METHODS

The study leveraged plan-do-study-act and Lean methodologies. The primary outcome was age at CP diagnosis. Data were acquired during the corresponding 9-month baseline and quarterly throughout study. Balancing measures were clinic no-show rates and parent perception of the diagnosis visit. Clinic teams conducted strengths, weaknesses, opportunities, and threats analyses, process flow evaluations, standardized assessments training, and parent questionnaires. Performance of a 3- to 4-month clinic visit was a critical process step because it included a Hammersmith Infant Neurologic Examination, a General Movements Assessment, and standardized assessments of motor function.

RESULTS

The age at CP diagnosis decreased from a weighted average of 19.5 (95% confidence interval 16.2 to 22.8) to 9.5 months (95% confidence interval 4.5 to 14.6), with P = .008; 3- to 4-month visits per site increased from the median (interquartile range) 14 (5.2-73.7) to 54 (34.5-152.0), with P < .001; and no-show rates were not different. Parent questionnaires revealed positive provider perception with improvement opportunities for information content and understandability.

CONCLUSIONS

Large-scale implementation of international guidelines for early detection of CP is feasible in diverse high-risk infant follow-up clinics. The initiative was received positively by families and without adversely affecting clinic operational flow. Additional parent support and education are necessary.

Outcomes from an Expanded Targeted Early Cytomegalovirus Testing Program

Objective This study aimed to determine the outcomes from an expanded targeted early congenital cytomegalovirus (cCMV) testing program.

Study Design A retrospective analysis of data was collected from June 2016 to April 2018 of patients who underwent expanded targeted early cCMV testing during the peri-implementation phase. Information regarding patient presentation, test type/result, and audiologic outcomes were collected. Chi-square and two-sample t-tests were performed.

Results A total of 754 patients underwent cCMV testing; during that period there were 56,947 births at 20 different hospitals. Reasons for completing cCMV testing included the following: (1) failed hearing screening (35.8%), (2) intrauterine growth restriction (IUGR) or small for gestational age (SGA) (29.1%), (3) sepsis (10.7%), (4) other/unknown (8.7%), (5) elevated liver enzymes or bilirubin (5.1%), (6) thrombocytopenia (5.1%), (7) central nervous system abnormalities (3.3%), and (8) mother with suspected cCMV infection (2.2%). The most frequent type of cCMV test performed was urine polymerase chain reaction (75.8%). A total of 21 (2.8%) patients tested positive for cCMV, of which 12 (57%) were symptomatic. This value represents a prevalence of 36.9 cCMV cases and 21.1 symptomatic cCMV cases diagnosed per 100,000 live births. Criteria most commonly associated with a positive testing were failed hearing screening (33.3%), IUGR/SGA (28.6%), and a mother with suspected cCMV infection (19.0%).

Conclusion Implementation of an expanded targeted early CMV testing program has the potential to identify symptomatic cCMV infants who would not be identified otherwise.

Targeted gene panel sequencing for the rapid diagnosis of acutely ill infants

Background

Exome/genome sequencing (ES/GS) have been recently used in neonatal and pediatric/cardiac intensive care units (NICU and PICU/CICU) to diagnose and care for acutely ill infants, but the effectiveness of targeted gene panels for these purposes remains unknown.

Methods

RapSeq, a newly developed panel targeting 4,503 disease‐causing genes, was employed on selected patients in our NICU/PICU/CICU. Twenty trios were sequenced from October 2015 to March 2017. We assessed diagnostic yield, turnaround times, and clinical consequences.

Results

A diagnosis was made in 10/20 neonates (50%); eight had de novo variants (ASXL1, CHD, FBN1, KMT2D, FANCB, FLNA, PAX3), one was a compound heterozygote for CHAT, and one had a maternally inherited GNAS variant. Preliminary reports were generated by 9.6 days (mean); final reports after Sanger sequencing at 16.3 days (mean). In all positive infants, the diagnosis changed management. In a case with congenital myasthenia, diagnosis and treatment occurred at 17 days versus 7 months in a historical control.

Conclusions

This study shows that a gene panel that includes the majority of known disease‐causing genes can rapidly identify a diagnosis in a large number of tested infants. Due to simpler deployment and interpretation and lower costs, this approach might represent an alternative to ES/GS in the NICU/PICU/CICU.

Abstract TP507: Sex-Related Differences in Neonatal Stroke: International Maternal Newborn Stroke Registry

Background: There is evidence that male neonates have higher incidences of ischemic stroke and associated limitations in brain repair compared to female neonates. We used data from the International Maternal Newborn Stroke Registry (IMNSR) to further explore neonatal sex differences in demographics, birth characteristics, stroke onset, and maternal factors.

Methods: Eleven international sites participated; 8 entered data for this analysis. Eligible participants with newborn (28 weeks gestation to 28 postnatal days) ischemic or hemorrhagic stroke or cerebral venous thrombosis were identified prospectively and retrospectively and enrolled. Preterm infants born before 28 weeks and neonates with germinal matrix intraventricular hemorrhage were excluded. We collected APGAR scores at 1 and 5 minutes, resuscitation status, demographics, stroke type, maternal and gestational age at birth, and mother’s health conditions at birth. Descriptive statistics were performed to identify differences in female versus male neonate cases related to demographics, pregnancy-related factors, and birth-related factors.

Results: We analyzed 68 cases, 38 males and 30 females. Median maternal age for all cases was 31 y (IQR 29-34). Compared to females, males were more likely to have a lower APGAR 1 score and receive resuscitation, and more likely to have a stroke onset within the first week of life. This data set did not show significant gender-related differences in stroke type, or maternal health concerns during pregnancy (Table).

Conclusions: We found that males with newborn strokes had more complications at birth and were more likely to have strokes present in the first week of life than females. Further research on the reasons for these sex differences is needed.

Rapid clinical diagnostic variant investigation of genomic patient sequencing data with iobio web tools

INTRODUCTION

Computational analysis of genome or exome sequences may improve inherited disease diagnosis, but is costly and time-consuming.

METHODS

We describe the use of iobio, a web-based tool suite for intuitive, real-time genome diagnostic analyses.

RESULTS

We used iobio to identify the disease-causing variant in a patient with early infantile epileptic encephalopathy with prior nondiagnostic genetic testing.

CONCLUSIONS

Iobio tools can be used by clinicians to rapidly identify disease-causing variants from genomic patient sequencing data.

Neonatal Magnesium Levels Between 24 and 48 Hours of Life and Outcomes for Epilepsy and Motor Impairment in Premature Infants

OBJECTIVE

Elevated rates of epilepsy and motor impairments including cerebral palsy are observed in children who were born prematurely. Maternal antenatal magnesium supplementation has been associated with decreased rates of cerebral palsy in infants born prematurely. Our objective was to determine whether the neonatal serum magnesium level between 24 and 48 hours after birth is associated with better long-term neurodevelopmental outcomes (epilepsy, motor impairment) in premature infants.

METHODS

We performed a retrospective cohort analysis in infants born less than 37-weeks gestation over a ten-year period. Prenatal, perinatal, and postnatal clinical and demographic information was collected. Crude and adjusted odds ratios were estimated under generalized linear models with generalized estimating equations to examine the association of the neonatal serum magnesium level between 24 and 48 hours after birth with the risk of epilepsy and/or motor impairment (spasticity; hypotonia; cerebral palsy).

RESULTS

The final cohort included 5461 infants born less than 37-weeks gestation from 2002 to 2011. The adjusted relative risk ratio for the combined outcomes of epilepsy and/or motor impairment, controlling for gestational age, current age, maternal magnesium supplementation, maternal steroid administration, five-minute Apgar score, neonatal infection, need for vasopressor use, and birth weight and with serum magnesium level as the main independent variable, was 0.85 (P = 0.24). Stratified analyses by gestational age less than 32 or greater than 32 weeks were not significantly associated with adverse neurodevelopmental outcome (risk ratio = 0.79 and 1.2, P = 0.12 and 0.49, respectively). A multivariate analysis for the risk of motor impairment alone had a risk ratio of 0.94 (P = 0.72).

CONCLUSION

This study demostrates that the neonatal magnesium level between 24 and 48 hours of life in premature infants is not significantly associated with the risk for developing epilepsy or motor impairment.