CHARGE syndrome: an update

Clinical Portrait of Cochlear Implantation in Patients With CHARGE Syndrome

OBJECTIVE

To examine the clinical characteristics and auditory performance of patients with CHARGE syndrome following cochlear implantation (CI), as well as the prognostic factors affecting auditory outcomes.

STUDY DESIGN

Retrospective cohort.

SETTING

Tertiary academic center.

METHODS

A retrospective chart review was performed in patients with CHARGE syndrome who underwent CI from 2007 to 2022. The category of auditory performance (CAP) score was used to assess the CI outcomes, and factors that may affect the speech outcomes were also evaluated.

RESULTS

In 14 children with CHARGE syndrome, 22 CIs were performed, 6 unilaterally and 8 bilaterally. The mean age at CI was 25.9 months (range: 10-62). All patients had ear abnormalities and developmental delays, and cochlear nerve deficiency (CND) was present in all ears. At the last follow-up (mean: 49.6 months), the mean CAP score improved significantly compared to the preoperative measure (from 0.36 ± 0.81 to 3.21 ± 1.70, P = .001), with 6 patients (42.9%) achieving a CAP score of 4 points or higher. However, between the unilateral and bilateral CI groups, the final CAP score or change in CAP score was similar. Factors including age, coloboma, and CND did not significantly affect speech outcomes (all P > .05).

CONCLUSION

Even though CHARGE syndrome features challenging anomalies, CI can be conducted safely and can offer effective contribution to significant speech improvement. Patients with CHARGE syndrome should be given the opportunity to undergo CI to maximize their audiological progress.

CHD7 regulates craniofacial cartilage development via controlling HTR2B expression

Mutations in the Chromodomain helicase DNA-binding protein 7 - coding gene (CHD7) cause CHARGE syndrome (CS). Although craniofacial and skeletal abnormalities are major features of CS patients, the role of CHD7 in bone and cartilage development remain largely unexplored. Here, using a zebrafish (Danio rerio) CS model, we show that chd7-/- larvae display abnormal craniofacial cartilage development and spinal deformities. The craniofacial and spine defects are accompanied by a marked reduction of bone mineralization. At the molecular level, we show that these phenotypes are associated with significant reduction in the expression levels of osteoblast differentiation markers. Additionally, we detected a marked depletion of collagen 2α1 in the cartilage of craniofacial regions and vertebrae, along with significantly reduced number of chondrocytes. Chondrogenesis defects are at least in part due to downregulation of htr2b, which we found to be also dysregulated in human cells derived from an individual with CHD7 mutation-positive CS. Overall, this study thus unveils an essential role for CHD7 in cartilage and bone development, with potential clinical relevance for the craniofacial defects associated with CS.

The Incidence and Outcomes for Children with Cleft Palate and/or Lip and CHARGE Syndrome

OBJECTIVES

Published literature on children with cleft palate and/or lip (CP + /-L) and CHARGE syndrome (CS) is limited. This study investigated cleft characteristics including surgery, and feeding and communication outcomes in children identified with CP + /-L and CS.

DESIGN

Retrospective cross-sectional review.

SETTING

Regional Referral Centre for Paediatric Cleft Surgery.

PATIENTS

All children diagnosed with CP + /-L and CS (based on clinical features and/or CHD7 mutation testing) between 1989-2019.

MAIN OUTCOME MEASURES

Cleft type, timing of CP + /-L repair, reasons for 'delayed' repair, feeding methods and communication modality.

RESULTS

Twenty-two children with CP + /-L and CS were identified. Cleft sub-types (%) were: Eleven (50%) had bilateral cleft lip and palate (BCLP), six (27%) had unilateral cleft lip and palate (UCLP) and five (23%) had cleft palate (CP). Cleft repair was delayed compared to protocol care for non-syndromic children with CP + /-L. Median age for lip repair + /- vomerine flap was 9 months (range 4-22 months), and palate repair was 21 months (range 11-40 months). Median age for isolated CP repair was 13 months (range 7-23). Surgery for cardiac anomalies (36%) before cleft repair, and (59%) were classed as having severe systemic disease at the time of cleft surgery. Only 27% of the children in this study had both full oral feeding and verbal communication.

CONCLUSIONS

Children with CP + /-L and CS had severe cleft types and complex medical problems leading to delayed cleft surgery. Feeding and speech outcomes were better in the children aged over ten years.

Detailed analysis of inner ear malformations in CHARGE syndrome patients - correlation with audiological results and proposal for computed tomography scans evaluation methodology

OBJECTIVES

The aim was to describe the spectrum of inner ear malformations in CHARGE syndrome and propose a Computed Tomography (CT) detailed scan evaluation methodology. The secondary aim was to correlate the CT findings with hearing thresholds.

METHODS

Twenty ears of ten patients diagnosed with CHARGE syndrome were subjected to CT analysis focusing on the inner ear and internal acoustic canal. The protocol used is presented in detail. ASSR results were analyzed and correlated with inner ear malformations.

RESULTS

Cochlear hypoplasia type III was the most common malformation found in 12 ears (60%). Cochlear hypoplasia type II, aplasia with a dilated vestibule, and rudimentary otocyst were also identified. In 20%, no cochlear anomaly was found. The lateral Semicircular Canal (SCC) absence affected 100% of ears, the absence of the posterior SCC 95%, and the superior SCC 65%. Better development of cochlea structures and IAC correlated significantly with the lower hearing thresholds.

CONCLUSION

This study demonstrated that rudimentary SCC or a complete absence of these SCCs was universally observed in all patients diagnosed with CHARGE syndrome. This finding supports the idea that inner ear anomalies are a hallmark feature of the CHARGE, contributing to its distinct clinical profile. The presence of inner ear malformations has substantial clinical implications. Audiological assessments are crucial for CHARGE syndrome, as hearing loss is common. Early detection of these malformations can guide appropriate interventions, such as hearing aids or cochlear implants, which may significantly improve developmental outcomes and communication for affected individuals. Recognizing inner ear malformations as a diagnostic criterion presents implications beyond clinical diagnosis. A better understanding of these malformations can advance the knowledge of CHARGE pathophysiology. It may also help guide future research into targeted therapies to mitigate the impact of inner ear anomalies on hearing and balance function.

LEVEL OF EVIDENCE: 4

Random walk with restart on multilayer networks: from node prioritisation to supervised link prediction and beyond

BACKGROUND

Biological networks have proven invaluable ability for representing biological knowledge. Multilayer networks, which gather different types of nodes and edges in multiplex, heterogeneous and bipartite networks, provide a natural way to integrate diverse and multi-scale data sources into a common framework. Recently, we developed MultiXrank, a Random Walk with Restart algorithm able to explore such multilayer networks. MultiXrank outputs scores reflecting the proximity between an initial set of seed node(s) and all the other nodes in the multilayer network. We illustrate here the versatility of bioinformatics tasks that can be performed using MultiXrank.

RESULTS

We first show that MultiXrank can be used to prioritise genes and drugs of interest by exploring multilayer networks containing interactions between genes, drugs, and diseases. In a second study, we illustrate how MultiXrank scores can also be used in a supervised strategy to train a binary classifier to predict gene-disease associations. The classifier performance are validated using outdated and novel gene-disease association for training and evaluation, respectively. Finally, we show that MultiXrank scores can be used to compute diffusion profiles and use them as disease signatures. We computed the diffusion profiles of more than 100 immune diseases using a multilayer network that includes cell-type specific genomic information. The clustering of the immune disease diffusion profiles reveals shared shared phenotypic characteristics.

CONCLUSION

Overall, we illustrate here diverse applications of MultiXrank to showcase its versatility. We expect that this can lead to further and broader bioinformatics applications.

Effects of 4 Testing Arena Sizes and 11 Types of Embryo Media on Sensorimotor Behaviors in Wild-Type and chd7 Mutant Zebrafish Larvae

The larval zebrafish is a highly versatile model across research disciplines, and the expanding use of behavioral analysis has contributed to many advances in neuropsychiatric, developmental, and toxicological studies, often through large-scale chemical and genetic screens. In the absence of standardized approaches to larval zebrafish behavior analysis, however, it is critical to understand the impact on behavior of experimental variables such as the size of testing arenas and the choice of embryo medium. Using a custom-built, modular high-throughput testing system, we examined the effects of 4 testing arena sizes and 11 types of embryo media on conserved sensorimotor behaviors in zebrafish larvae. Our data show that testing arena size impacts acoustic startle sensitivity and kinematics, as well as spontaneous locomotion and thigmotaxis, with fish tested in larger arenas displaying reduced startle sensitivity and increased locomotion. We also find that embryo media can dramatically affect startle sensitivity, kinematics, habituation, and prepulse inhibition, as well as spontaneous swimming, turning, and overall activity. Common medium components such as methylene blue and high calcium concentration consistently reduced startle sensitivity and locomotion. To further address how the choice of embryo medium can impact phenotype expression in zebrafish models of disease, we reared chd7 mutant larvae, a model of CHARGE syndrome with previously characterized morphological and behavioral phenotypes, in five different types of media and observed impacts on all phenotypes. By defining the effects of these key extrinsic factors on larval zebrafish behavior, these data can help researchers select the most appropriate conditions for their specific research questions, particularly for genetic and chemical screens.

Digenic CHD7 and SMCHD1 inheritance Unveils phenotypic variability in a family mainly presenting with hypogonadotropic hypogonadism

Objectives

CHARGE syndrome is a congenital hereditary condition involving multiple systems. Patients are easily misdiagnosed with idiopathic hypogonadotropic hypogonadism (IHH) due to the overlap of clinical manifestations. An accurate clinical diagnosis remains challenging when the predominant clinical manifestation resembles hypogonadotropic hypogonadism.

Methods

This original research is conducted based on the genetic finding and analysis of clinical cases. Whole-exome sequencing (WES) and in-silico analyse were performed on two sisters to investigate the pathogenesis in this family. Homology modelling was conducted to evaluate structural changes in the variants.

Results

WES and Sanger sequencing revealed two siblings carrying a nonsense mutation (NM_017780.4: c.115C > T) in exon 2 of CHD7 inherited from a mildly affected mother and a missense mutation (NM_015295.3: c.2582T > C) in exon 20 of SMCHD1 inherited from an asymptomatic father. The nonsense mutation in CHD7 was predicted to generate nonsense-mediated decay, whereas the missense mutation in SMCHD1 decreased protein stability.

Conclusions

We identified digenic CHD7 and SMCHD1 mutations in IHH-associated diseases for the first time and verified the synergistic role of oligogenic inheritance. It was also determined that WES is an effective tool for distinguishing diseases with overlapping features and establishing a molecular diagnosis for cases with digenic or oligogenic hereditary disorders, which is beneficial for timely treatment, and family genetic counseling.

Syndromic Hearing Loss in Children

Pattern recognition of specific temporal bone radiological phenotypes, in association with abnormalities in other organ systems, is critical in the diagnosis and management of syndromic causes of hearing loss. Several recent publications have demonstrated the presence of specific radiological appearances, allowing precise genetic and/or syndromic diagnosis, in the right clinical context. This review article aims to provide an extensive but practical guide to the radiologist dealing with syndromic causes of hearing loss.

Effects of 4 testing arena sizes and 11 types of embryo media on sensorimotor behaviors in wild-type and chd7 mutant zebrafish larvae: Media and arena size impact zebrafish behavior

The larval zebrafish is a highly versatile model across research disciplines, and the expanding use of behavioral analysis has contributed to many advances in neuro-psychiatric, developmental, and toxicological studies, often through large-scale chemical and genetic screens. In the absence of standardized approaches to larval zebrafish behavior analysis, however, it is critical to understand the impact on behavior of experimental variables such as the size of testing arenas and the choice of embryo medium. Using a custom-built, modular high-throughput testing system, we examined the effects of 4 testing arena sizes and 11 types of embryo media on conserved sensorimotor behaviors in zebrafish larvae. Our data show that testing arena size impacts acoustic startle sensitivity and kinematics as well as spontaneous locomotion and thigmotaxis, with fish tested in larger arenas displaying reduced startle sensitivity and increased locomotion. We also find that embryo media can dramatically affect startle sensitivity, kinematics, habituation, and pre-pulse inhibition, as well as spontaneous swimming, turning, and overall activity. Common media components such as methylene blue and high calcium concentration consistently reduced startle sensitivity and locomotion. To further address how the choice of embryo medium can impact phenotype expression in zebrafish models of disease, we reared chd7 mutant larvae, a model of CHARGE syndrome with previously characterized morphological and behavioral phenotypes, in 5 different types of media and observed impacts on all phenotypes. By defining the effects of these key extrinsic factors on larval zebrafish behavior, these data can help researchers select the most appropriate conditions for their specific research questions, particularly for genetic and chemical screens.

Predicting the clinical trajectory of feeding and swallowing abilities in CHARGE syndrome

To date, the feeding and oral-motor abilities of patients with CHARGE syndrome (CS) have not been longitudinally assessed. This study aims to investigate the level of these abilities at different ages and evaluate how they evolve during growth. We retrospectively analysed oral-motor features of 16 patients with molecularly confirmed CS (age range 4-21 years old; mean 11 years; SD 6 years; median 10 years). Nearly 100% of CS new-borns had weak sucking at birth, and half of them demonstrated poor coordination between breathing and swallowing. Over time, the percentages of children with tube feeding dependence (60% at birth) faced a slow but steady decrease (from 33% at 6 months, 25% at 12 months, to 13% at school age) in tandem with the decreasing risk of aspiration. The ability of eating foods requiring chewing was achieved at school age, after the acquisition of an adequate oral sensory processing. A mature chewing pattern with a variety of food textures was not achieved by more than half of patients, including those requiring artificial enteral nutrition. Most patients started prolonged oral-motor treatments with speech language therapists in early childhood.

CONCLUSIONS

Although feeding and swallowing disorders are constant features in CS patients, a slow and gradual development of feeding abilities occurs in most cases. Rehabilitation plays a key role in overcoming structural and functional difficulties and attaining appropriate eating skills.

WHAT IS KNOWN

• Feeding problems and swallowing dysfunction have been noted in CHARGE syndrome. • The involvement of multiple factors, including structural problems in the mouth, throat, or esophagus, and neurological impairment, make feeding a complicated task in CHARGE individuals.

WHAT IS NEW

• Dysphagia gradually improves in most CHARGE children over time, though with a wide interindividual variability. • The percentages of children with tube feeding dependence decrease over time from 60% at birth to 33% at 6 months and 13% at school age.

Case report: Functional characterization of a novel CHD7 intronic variant in patients with CHARGE syndrome

Background: Because CHARGE syndrome is characterized by high clinical variability, molecular confirmation of the clinical diagnosis is of pivotal importance. Most patients have a pathogenic variant in the CHD7 gene; however, variants are distributed throughout the gene and most cases are due to de novo mutations. Often, assessing the pathogenetic effect of a variant can be challenging, requiring the design of a unique assay for each specific case. Method: Here we describe a new CHD7 intronic variant, c.5607+17A>G, identified in two unrelated patients. In order to characterize the molecular effect of the variant, minigenes were constructed using exon trapping vectors. Results: The experimental approach pinpoints the pathogenetic effect of the variant on CHD7 gene splicing, subsequently confirmed using cDNA synthetized from RNA extracted from patient lymphocytes. Our results were further corroborated by the introduction of other substitutions at the same nucleotide position, showing that c.5607+17A>G specifically alters splicing possibly due to the generation of a recognition motif for the recruitment of a splicing effector. Conclusion: Here we identify a novel pathogenetic variant affecting splicing, and we provide a detailed molecular characterization and possible functional explanation.

Patterns of multiple congenital anomalies in the National Birth Defect Prevention Study: Challenges and insights

BACKGROUND

About 20%-30% of children with birth defects have multiple major birth defects in more than one organ system, often referred to as multiple congenital anomalies (MCAs). Evaluating the patterns of MCAs can provide clues to the underlying causes, pathogenic mechanisms, and developmental pathways. We sought to explore selected patterns of MCAs within the National Birth Defects Prevention Study (NBDPS), a population-based, case-control study that excluded cases attributed to known chromosomal or single-gene abnormalities.

METHODS

We defined MCAs as having two or more NBDPS-eligible birth defects and calculated the adjusted observed-to-expected ratio for all observed MCA patterns using co-occurring defect analysis.

RESULTS

Of the 50,186 case infants eligible for NBDPS, 2,734 (3.7%) had at least two eligible birth defects. We observed 209 distinct 2-way combinations of birth defects, 297 distinct 3-way combinations, 179 distinct 4-way combinations, and 69 distinct 5-way combinations. Sacral agenesis had the largest proportion of cases with MCAs (70%), whereas gastroschisis had the lowest (3%). Among the cases with MCAs, 63% had a heart defect, 23% had an oral cleft, and 21% had anorectal atresia/stenosis. Of the patterns with adjusted observed-to-expected ratios in the top 20%, most were consistent with the known associations or syndromes, including VATER/VACTERL association and CHARGE syndrome.

CONCLUSIONS

Most but not all patterns that had the highest adjusted observed-to-expected ratios were instances of known syndromes or associations. These findings highlight the importance of considering birth defect combinations that suggest syndromic patterns in the absence of a formal syndromic diagnosis. New approaches for screening for sequences and associations, and VATER/VACTERL in particular, in surveillance systems with limited resources for manual review may be valuable for improving surveillance system quality. The observed MCA patterns within NBDPS may help focus future genetic studies by generating case groups of higher yield.

Mammalian Resilience Revealed by a Comparison of Human Diseases and Mouse Models Associated With DNA Helicase Deficiencies

Maintaining genomic integrity is critical for sustaining individual animals and passing on the genome to subsequent generations. Several enzymes, such as DNA helicases and DNA polymerases, are involved in maintaining genomic integrity by unwinding and synthesizing the genome, respectively. Indeed, several human diseases that arise caused by deficiencies in these enzymes have long been known. In this review, the author presents the DNA helicases associated with human diseases discovered to date using recent analyses, including exome sequences. Since several mouse models that reflect these human diseases have been developed and reported, this study also summarizes the current knowledge regarding the outcomes of DNA helicase deficiencies in humans and mice and discusses possible mechanisms by which DNA helicases maintain genomic integrity in mammals. It also highlights specific diseases that demonstrate mammalian resilience, in which, despite the presence of genomic instability, patients and mouse models have lifespans comparable to those of the general population if they do not develop cancers; finally, this study discusses future directions for therapeutic applications in humans that can be explored using these mouse models.

A case of Gross E esophageal atresia discovered following a unique clinical course

The patient was a 15 months-old boy who had been diagnosed CHARGE syndrome, which is a multiple congenital anomaly syndrome caused by mutations in the CHD7 gene. Mechanical ventilation management was initiated 2 hours after birth for dysphagia and respiratory failure, and tracheotomy was performed 3 months after birth for dysphagia and failed extubation. He was repeatedly hospitalized due to pneuomoniae. Approximately 1 year after birth, the boy had two consecutive episodes of sudden ventilatory insufficiency while replacing the tracheotomy cannula. A bronchoscopic examination under general anesthesia revealed a tracheoesophageal fistula directly below the tracheostomy. The patient was diagnosed with Gross E esophageal atresia, and we speculated that the cannula migrated to the esophagus via the fistula during tracheostomy cannula replacement. Gross E esophageal atresia is a rare disease. Its diagnosis is often delayed, and it is discovered by recurrent pneumonia in many cases. A tracheoesophageal fistula may also be found in children with deformities of the respiratory system. Furthermore, tracheoesophageal fistulae are often found in the neck. Therefore, when sudden ventilatory insufficiency occurs in a child with a tracheostomy after replacing the tracheostomy cannula, caution must be exercised since the cannula may have migrated to the esophagus via a fistula. J. Med. Invest. 69 : 141-144, February, 2022.

Clinical spectrum of female genital malformations in prenatal diagnosis

Introduction

Fetal genital malformations represent a rare and heterogeneous group of congenital malformations of the disorders of sexual development (DSD) spectrum.

Methods

A thorough literature review on the main topics in the prenatal approach towards DSD was conducted.

Results

First, a thorough overview on prenatal characteristics of the most common fetal genital malformations of ovaries, uterus and external genitalia, and second, a standardized approach for differential diagnosis in the presence of direct and indirect prenatal signs of DSDs.

Conclusions

This review is mainly directed towards the aspects of female genital malformations with  aspects of male DSD explained as well to aid in the prenatal differential diagnosis.

Phenotypic spectrum of patients with mutations in CHD7: clinical implications of endocrinological findings

OBJECTIVE

Heterozygous CHD7 mutations cause a broad spectrum of clinical phenotypes ranging from typical CHARGE syndrome to self-limited delayed puberty. This study aimed to investigate the clinical characteristics of endocrine dysfunction in patients with CHD7 mutations.

METHODS

The clinical features and endocrine findings from 30 patients with CHD7 variants were retrospectively reviewed. A diagnosis of CHARGE syndrome was based on the Verloes diagnostic criteria.

RESULTS

Seventeen patients fulfilled the criteria for typical CHARGE syndrome, one patient for partial/incomplete CHARGE, and the remaining eleven patients had atypical CHARGE syndrome. One patient was diagnosed with Kallmann syndrome and unilateral deafness. The most frequently observed features were inner ear anomalies (80.0%), intellectual disability (76.7%), and external ear anomalies (73.3%). The mean height and weight SDSs at diagnosis were -2.6 ± 1.3 and -2.2 ± 1.8, respectively. Short stature was apparent in 18 patients (60%), and 1 patient was diagnosed with growth hormone deficiency. Seventeen males showed genital hypoplasia, including micropenis, cryptorchidism, or both. Seven patients after pubertal age had hypogonadotropic hypogonadism with hyposmia/anosmia and olfactory bulb hypoplasia. Truncating CHD7 mutations were the most common (n = 22), followed by missense variants (n = 3), splice-site variants (n = 2), and large deletion (n = 2).

CONCLUSIONS

A diverse phenotypic spectrum was observed in patients with CHD7 variants, and endocrine defects such as short stature and delayed puberty occurred in most patients. Endocrine evaluation, especially for growth and pubertal impairment, should be performed during diagnosis and follow-up to improve the patient's quality of life.

De novo Splice Site Mutation of the CHD7 Gene in a Chinese Patient with Typical CHARGE Syndrome

INTRODUCTION

CHARGE syndrome (CS, OMIM 214800) is a rare genetic disease characterized by multiple congenital abnormalities, including coloboma, heart defect, atresia of the choanae, retardation of development, genital anomalies, and ear anomalies/deafness. The syndrome is mainly caused by a heterozygous variant in the chromodomain helicase DNA-binding protein 7 (CHD7) gene that encodes the CHD7 protein, involved in the ATP-dependent remodeling of chromatin.

METHODS

In this study, the next-generation sequencing targeted panel was used to detect a de novo variant c.3523-2A>G in the CHD7 gene in a patient with severe CS, congenital heart disease, left coloboma of the choroid, cryptorchidism, and congenital deafness. The Sanger sequencing confirmed the variant and clarified it as de novo variant by short tandem repeat analysis in the patient family. We analyzed the effect of a variant by Minigene assay to evaluate the pathogenicity of the variant.

RESULTS

In summary, cDNA analysis confirmed that c.3523-2A>G variant activates a cryptic splice site, resulting in 172 base pair missing in exon 15, leading to the premature truncation of the CHD7 protein (p.V1175Afs*11).

CONCLUSION

The present study functionally characterized the novel c.3523-2A>G variant in CHD7, providing further confirmatory evidence that it is associated with CS.

Rare Genetic Syndromes and Oral Anomalies: A Review of the Literature and Case Series with a New Classification Proposal

Rare genetic syndromes, conditions with a global average prevalence of 40 cases/100,000 people, are associated with anatomical, physiological, and neurological anomalies that may affect different body districts, including the oral district. So far, no classification of oral abnormalities in rare genetic syndromes is present in the literature. The aim of this narrative review is to analyze literature on rare genetic syndromes affecting dento-oro-maxillofacial structures (teeth, maxillary bones, oral soft tissues, or mixed) and to propose a classification according to the detected oral abnormalities. In addition, five significant cases of rare genetic syndromes are presented. The Scale for the Assessment of Narrative Review Articles (SANRA) was followed for this review. From 674 papers obtained through PubMed search, 351 were selected. Sixty-two rare genetic syndromes involving oral manifestations were found and classified. The proposed classification aims to help the clinician to easily understand which dento-oro-maxillofacial findings might be expected in the presence of each rare genetic syndrome. This immediate framework may both help in the diagnosis of dento-oro-maxillofacial anomalies related to the underlying pathology as well as facilitate the drafting of treatment plans with the involvement of a multidisciplinary team.

CHARGE syndrome: A case report of two new CDH7 gene mutations

CHARGE syndrome is a genetic disorder comprising the following clinical features: coloboma, heart defects, choanal atresia, retardation (of growth and development), as well as genitourinary and ear abnormalities. This syndrome is caused by mutations in the CDH7 gene, located on chromosome 8 (8q12). We present two new gene mutations in two patients with CHARGE syndrome, not previously reported in the scientific literature. Both of these patients clearly demonstrate the difference in the clinical expression of this syndrome, with patient 1 having a greater clinical severity compared to patient 2. We conclude that although in the scientific literature to date there is no clear correlation between a patient's genotype and phenotype expression, we can assume from the cases we present that a correlation does in fact exist. Specifically, missense mutations (as in case of patient 2) are associated with milder clinical expression, whereas mutations which result in truncation of the CDH7 protein (as in the case of patient 1 having a nonsense mutation) may be associated with a more severe clinical expression.

Persistent Trigeminal Artery: A Novel Imaging Finding in CHARGE Syndrome

BACKGROUND AND PURPOSE

Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and/or development, Genital and/or urinary abnormalities, Ear abnormalities and deafness (CHARGE) syndrome is an autosomal dominant genetic disorder with evolving clinical diagnostic criteria. Recently, a number of additional anomalies have been described in this syndrome, which may aid in early diagnosis, particularly in incomplete phenotypes or atypical cases. The persistent trigeminal artery is an embryonic carotid-vertebral anastomosis, rarely seen in the healthy population, with a reported prevalence of 0.4%. Because we had observed the persistent trigeminal artery in patients with CHARGE syndrome, this study aimed to explore the prevalence of the persistent trigeminal artery in this syndrome.

MATERIALS AND METHODS

A retrospective study was performed at our tertiary center. MR imaging studies, clinical records, and genetic results were reviewed for patients diagnosed with CHARGE syndrome between 2006 and 2019. The prevalence of the persistent trigeminal artery in patients with CHARGE syndrome was recorded and compared with other established diagnostic criteria.

RESULTS

Twenty-five patients with CHARGE syndrome were included. The persistent trigeminal artery was demonstrated on MR imaging in 14/25 (56%) patients and was seen more frequently than 4 of 9 other established diagnostic criteria in our cohort. When individual major or minor diagnostic criteria were absent, the persistent trigeminal artery was still demonstrated on MR imaging in 52%-67% of these patients with CHARGE syndrome.

CONCLUSIONS

The prevalence of the persistent trigeminal artery in CHARGE syndrome of 56% is higher than that of some other established diagnostic criteria and much higher than that in the general population. The persistent trigeminal artery may be a useful addition to the expanding phenotype of CHARGE syndrome, supplementing other diagnostic criteria. Radiologists should be aware of this novel finding demonstrable on MR imaging.

Otopathologic Abnormalities in CHARGE Syndrome

OBJECTIVE

To perform an otopathologic analysis of temporal bones (TBs) with CHARGE syndrome.

STUDY DESIGN

Otopathologic study of human TB specimens.

SETTING

Otopathology laboratories.

METHODS

From the otopathology laboratories at the University of Minnesota and Massachusetts Eye and Ear Infirmary, we selected TBs from donors with CHARGE syndrome. These TBs were serially sectioned at a thickness of 20 µm, and every 10th section was stained with hematoxylin and eosin. We performed otopathologic analyses of the external ear, middle ear (middle ear cleft, mucosal lining, ossicles, mastoid, and facial nerve), and inner ear (cochlea, vestibule, internal auditory canal, and cochlear and vestibular nerves). The gathered data were statistically analyzed.

RESULTS

Our study included 12 TBs from 6 donors. We found a high prevalence of abnormalities affecting the ears. The most frequent findings were stapes malformation (100%), aberrant course of the facial nerve (100%) with narrow facial recess (50%), sclerotic and hypodeveloped mastoids (50%), cochlear (100%) and vestibular (83.3%) hypoplasia with aplasia of the semicircular canals, hypoplasia and aplasia of the cochlear (66.6%) and vestibular (91.6%) nerves, and narrowing of the bony canal of the cochlear nerve (66.6%). The number of spiral ganglion and Scarpa's ganglion neurons were decreased in all specimens (versus normative data).

CONCLUSIONS

In our study, CHARGE syndrome was associated with multiple TB abnormalities that may severely affect audiovestibular function and rehabilitation.

What can clinical immunology learn from inborn errors of epigenetic regulators?

The epigenome is at the interface between environmental factors and the genome, regulating gene transcription, DNA repair, and replication. Epigenetic modifications play a crucial role in establishing and maintaining cell identity and are especially crucial for neurology, musculoskeletal integrity, and the function of the immune system. Mutations in genes encoding for the components of the epigenetic machinery lead to the development of distinct disorders, especially involving the central nervous system and host defense. In this review, we focus on the role of epigenetic modifications for the function of the immune system. By studying the immune phenotype of patients with monogenic mutations in components of the epigenetic machinery (inborn errors of epigenetic regulators), we demonstrate the importance of DNA methylation, histone modifications, chromatin remodeling, noncoding RNAs, and mRNA processing for immunity. Moreover, we give a short overview on therapeutic strategies targeting the epigenome.

Cardiac Neural Crest

Cardiac neural crest (CNC) cells are pluripotent cells derived from the dorsal neural tube that migrate and contribute to the remodeling of pharyngeal arch arteries and septation of the cardiac outflow tract (OFT). Numerous molecular cascades regulate the induction, specification, delamination, and migration of the CNC. Extensive analyses of the CNC ranging from chick ablation models to molecular biology studies have explored the mechanisms of heart development and disease, particularly involving the OFT and aortic arch (AA) system. Recent studies focus more on reciprocal signaling between the CNC and cells originated from the second heart field (SHF), which are essential for the development of the OFT myocardium, providing new insights into the molecular mechanisms underlying congenital heart diseases (CHDs) and some human syndromes.

CHARGE syndrome in the era of molecular diagnosis: Similar outcomes in those without coloboma or choanal atresia

CHARGE syndrome (OMIM 214800) is a condition characterized by multisystem involvement with CHD7 pathogenic mutations leading to disease in the majority of patients. Discovery of the molecular cause of CHARGE unmasked a larger phenotypic spectrum than was previously appreciated. Within our interdisciplinary CHARGE syndrome program, we sought to characterize our CHD7-positive CHARGE cohort without coloboma or choanal atresia, highlighting complications and outcomes. We describe 18 individuals with CHD7-confirmed diagnosis from 15 families. The most sensitive finding in the cohort was temporal bone malformations, present in 13/15 individuals. Individuals had an average of 1.6 major features and 3.3 minor features defined by the Blake et al. guidelines. Despite lack of major features or major malformations, the majority of individuals continued to have difficulties with pneumonia, aspiration, secretion management and motility issues that greatly impacted their lives. Our findings illustrate the need for molecular testing and timely recognition given that the major co-morbidities are frequently experienced by patients with the mildest clinical spectrum of CHARGE syndrome.

CHD7 regulates cardiovascular development through ATP-dependent and -independent activities

CHD7 encodes an ATP-dependent chromatin remodeling factor. Mutation of this gene causes multiple developmental disorders, including CHARGE (Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth/development, Genital abnormalities, and Ear anomalies) syndrome, in which conotruncal anomalies are the most prevalent form of heart defects. How CHD7 regulates conotruncal development remains unclear. In this study, we establish that deletion of Chd7 in neural crest cells (NCCs) causes severe conotruncal defects and perinatal lethality, thus providing mouse genetic evidence demonstrating that CHD7 cell-autonomously regulates cardiac NCC development, thereby clarifying a long-standing controversy in the literature. Using transcriptomic analyses, we show that CHD7 fine-tunes the expression of a gene network that is critical for cardiac NCC development. To gain further molecular insights into gene regulation by CHD7, we performed a protein-protein interaction screen by incubating recombinant CHD7 on a protein array. We find that CHD7 directly interacts with several developmental disorder-mutated proteins including WDR5, a core component of H3K4 methyltransferase complexes. This direct interaction suggested that CHD7 may recruit histone-modifying enzymes to target loci independently of its remodeling functions. We therefore generated a mouse model that harbors an ATPase-deficient allele and demonstrates that mutant CHD7 retains the ability to recruit H3K4 methyltransferase activity to its targets. Thus, our data uncover that CHD7 regulates cardiovascular development through ATP-dependent and -independent activities, shedding light on the etiology of CHD7-related congenital disorders. Importantly, our data also imply that patients carrying a premature stop codon versus missense mutations will likely display different molecular alterations; these patients might therefore require personalized therapeutic interventions.

Relationship Between Motor Skills, Balance, and Physical Activity in Children with CHARGE Syndrome

Introduction:

Children with CHARGE syndrome often show delays in balance and motor skills due to multisensory impairments. Research also suggests that children with CHARGE syndrome have fewer opportunities to engage in physical activity. However, little research has examined the relationship among all of these variables. Thus, the purpose of this study was to examine the relationship between balance, motor skills, and physical activity.

Methods:

Participants consisted of 37 children with CHARGE syndrome aged 3–16 years who could walk independently. Parents of each child with CHARGE syndrome completed a demographics questionnaire and the Physical Activity Questionnaire for Children or Adolescents. Their child completed the Mini-BEST balance test and five motor skills (run, jump, slide, kick, and throw) from the Test of Gross Motor Development II.

Results:

Results indicate that anticipatory control had significant positive correlations with all five motor skills, sensory orientation with three motor skills, and reactive postural control and dynamic gait with two motor skills. Running was the only variable that had a significant positive correlation with physical activity.

Discussion:

The findings indicate that balance, especially anticipatory control, plays an important role in fundamental motor skills of children with CHARGE syndrome. There is also a strong connection between physical activity and running competence for this population; however, since this is based on a correlational analysis, the direction of the relationship is unclear.

Implications for practitioners:

Physical education teachers should work with students with CHARGE syndrome on increasing balance and motor skill performance to give them the competence and confidence to engage in physical activity. Moreover, parents can help by engaging in physical activity with their child at an early age and seeking out additional physical activity opportunities for their child outside of the physical education and school setting.

Should autism spectrum disorder be considered part of CHARGE syndrome? A cross-sectional study of 46 patients

Background

Behavioral problems are an important issue for people with CHARGE syndrome. The similarity of their behavioral traits with those of people with autism raises questions. In a large national cross-sectional study, we used specific standardized tools for diagnosing autism (Autism Diagnostic Interview-Revised and Diagnostic and Statistical Manual of Mental Disorders, 5th edition, DSM-5) and evaluating behavioral disorders (Developmental Behavior Checklist-Parents, DBC-P) to investigate a series of individuals with CHARGE syndrome, defined by Verloes’s criteria. We evaluated their adaptive functioning level and sensory particularities and extracted several data items from medical files to assess as potential risk factors for autism and/or behavioral disorders.

Results

We investigated 64 individuals with CHARGE syndrome (35 females; mean age 10.7 years, SD 7.1 years). Among 46 participants with complete results for the Autism Diagnostic Interview-Revised (ADI-R), 13 (28%) had a diagnosis of autism according to the ADI-R, and 25 (54%) had a diagnosis of autism spectrum disorder (ASD) according to the DSM-5 criteria. The frequency of autistic traits in the entire group was a continuum. We did not identify any risk factor for ASD but found a negative correlation between the ADI-R score and adaptive functioning level. Among 48 participants with data for the DBC-P, 26 (55%) had behavioral disorders, which were more frequent in patients with radiological brain anomalies, impaired adaptive functioning, later independent walking, and more sensory particularities.

Conclusions

ASD should be considered to be an independent risk requiring early screening and management in children born with CHARGE syndrome.

Nasal cavity shape in unilateral choanal atresia and the role of fetal ventilation in facial growth

OBJECTIVE

The respiratory movements of fetal amniotic fluid areconsidered by certains cleft surgery teams to contribute to the growth of the nasal cavities (NC). To assess this functional hypothesis, we considered a group of patients with unilateral choanal atresia (CA) as a model of unilateral absence of amniotic fluid flux in the NC, and compared their NCs shape to age-matched controls.

MATERIAL AND METHODS

Three-dimensional reconstructions of NC were performed using Avizo 9.7 (Thermo Fisher Scientific, MA, USA), based on CT-scans of 32 patients with unilateral CA and 96 age- and gender-matched controls. Landmarks were placed on anatomical structures of NC. Procrustes superimpositions and principal component analysis were performed. Anatomically relevant Euclidean distances were computed using the coordinates of selected landmarks - maxillary length, piriform orifice width, choanal width - and tested using multivariate analysis. Growth rates between patients and controls for these distances were screened for correlations.

RESULTS

The atretic NC was significantly deformed when compared to the control cases: Procrustes distance was 0.28 (P<0.0001). The maxillary length and width of the atretic choana were significantly decreased compared to controls (-2.95mm and -1.35mm respectively, P<0.001). There were no differences in growth rates between CA and controls, except for the choanal width on the atretic side.

CONCLUSION

NCs in CA were significantly different from controls. More precisely, the maxillary length was significantly reduced in the CA group. There was no other major shape difference between the NC in CA and controls. NC seems to develop despite abnormal fetal ventilation.

CHARGE syndrome: genetic aspects and dental challenges, a review and case presentation

Background

CHARGE syndrome (CS) is a rare genetic condition (OMIM #214800). The condition has a variable phenotypic expression. Historically, the diagnosis of CHARGE syndrome was based on the presence of specific clinical criteria. The genetic aetiology of CS has since been elucidated and attributed to pathogenic variation in the CHD7 gene (OMIM 608892) at chromosome locus 8q12.

Case presentation

A South African female of mixed ancestry heritage, aged 4 years, was referred for dental assessment to the Faculty of Dentistry, University of the Western Cape, in 2018. She had a diagnosis of CHARGE syndrome confirmed by a Medical Geneticist from the Division of Molecular Biology and Human Genetics at the University of Stellenbosch.

The patient had a long prior history of health and developmental problems, with the correct diagnosis becoming apparent over time. She presented with many oral and craniofacial features warranting consideration by the dentist including micrognathia, hypoplastic nasal bones, cranial nerve dysfunction, bruxism, craniofacial anomalies and compromised sensory perception. The treatment was mainly preventive and, although she fed through a percutaneous endoscopic gastrostomy tube (PEG), maintenance of her oral hygiene was necessitated.

Conclusion: CS is a multisystem condition and the optimal care for an individual is with a specialist multidisciplinary team. The numerous systemic problems affecting these individuals take precedence in their care, and often there is neglect of their dental concerns. Given the abnormalities frequently present in the oral and craniofacial region, the authors recommend that a team of dental and other medical specialists be involved in the management of individuals with CS.

Chemical-induced craniofacial anomalies caused by disruption of neural crest cell development in a zebrafish model

Background

Craniofacial anomalies are among the most frequent birth defects worldwide, and are thought to be caused by gene‐environment interactions. Genetically manipulated zebrafish simulate human diseases and provide great advantages for investigating the etiology and pathology of craniofacial anomalies. Although substantial advances have been made in understanding genetic factors causing craniofacial disorders, limited information about the etiology by which environmental factors, such as teratogens, induce craniofacial anomalies is available in zebrafish.

Results

Zebrafish embryos displayed craniofacial malformations after teratogen treatments. Further observations revealed characteristic disruption of chondrocyte number, shape and stacking. These findings suggested aberrant development of cranial neural crest (CNC) cells, which was confirmed by gene expression analysis of the CNC. Notably, these observations suggested conserved etiological pathways between zebrafish and mammals including human. Furthermore, several of these chemicals caused malformations of the eyes, otic vesicle, and/or heart, representing a phenocopy of neurocristopathy, and these chemicals altered the expression levels of the responsible genes.

Conclusions

Our results demonstrate that chemical‐induced craniofacial malformation is caused by aberrant development of neural crest. This study indicates that zebrafish provide a platform for investigating contributions of environmental factors as causative agents of craniofacial anomalies and neurocristopathy.

A case series of CHARGE syndrome: identification of key features for a neonatal diagnosis

BACKGROUND

An early diagnosis of CHARGE syndrome is challenging, especially for the primary care physicians who often take care of neonates with multiple congenital anomalies. Here we report eight cases of CHARGE syndrome whose diagnosis was made early in life with the intent to identify the most helpful features allowing a prompt clinical diagnosis.

METHODS

Medical records of patients with CHARGE syndrome whose diagnosis was made at the Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico in Milan, Italy were retrospectively reviewed.

RESULTS

Taken together, these patients reflect the considerable phenotypic variability of the syndrome; in one patient, the diagnosis was made immediately after birth because all the major criteria were met. In six patients, presenting with relatively nonspecific defects, a temporal bone computerized tomography scan was essential to achieve the correct diagnosis. In one patient, the diagnosis was made later than the others were. A careful examination revealed the presence of outer, middle, and inner ear anomalies: these elements, in the absence of any additional major criteria, represented for us an important diagnostic clue.

CONCLUSIONS

This article suggests that an accurate evaluation of the ear should be made every time CHARGE syndrome is considered as a likely diagnosis even when the standard criteria are not fulfilled.

CHARGE syndrome associated with (I1460Rfs*15) frameshift mutation of CHD7 gene in a patient with arteria lusoria and horseshoe kidney

CHARGE syndrome is an autosomal dominant condition caused by mutations in the chromodomain helicase DNA binding protein 7 (CHD7) gene. The present study reported on the case of a 16-month-old female with plurimalformative syndrome, whose etiology was identified by clinical whole-exome sequencing (WES) analysis. Clinical and follow-up assessments identified multiple craniofacial dysmorphisms, congenital defects and functional symptoms, including dysphagia and Marcus Gunn jaw winking synkinesis. Trio-WES analysis was performed for the patient and their parents and the presence of CHARGE syndrome was further indicated using single-molecule real-time sequencing. A de novo pathogenic variant, c.4379_4380del (p.Ile1460Argfs^*15), was identified in exon 19 of the CHD7 gene, which resulted in a premature translational stop signal. Trio-WES analysis was used for further investigation, indicating that neither of the patient's parents had the mutation and confirming its de novo nature. To the best of our knowledge, the case of the present study was the first reported case of CHARGE syndrome in Romania with congenital defects including an aberrant right subclavian artery and a horseshoe kidney. CHARGE syndrome was diagnosed in the patient based on the pathogenic mutation in the CHD7 gene. To the best of our knowledge, the present case report is the first to suggest that the CHD7 gene variant is associated with CHARGE syndrome.

Genetics of syndromic ocular coloboma: CHARGE and COACH syndromes

Optic fissure closure defects result in uveal coloboma, a potentially blinding condition affecting between 0.5 and 2.6 per 10,000 births that may cause up to 10% of childhood blindness. Uveal coloboma is on a phenotypic continuum with microphthalmia (small eye) and anophthalmia (primordial/no ocular tissue), the so-called MAC spectrum. This review gives a brief overview of the developmental biology behind coloboma and its clinical presentation/spectrum. Special attention will be given to two prominent, syndromic forms of coloboma, namely, CHARGE (Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, and Ear anomalies/deafness) and COACH (Cerebellar vermis hypoplasia, Oligophrenia, Ataxia, Coloboma, and Hepatic fibrosis) syndromes. Approaches employed to identify genes involved in optic fissure closure in animal models and recent advances in live imaging of zebrafish eye development are also discussed.

Fetal Alcohol Spectrum Disorder: Embryogenesis Under Reduced Retinoic Acid Signaling Conditions

Fetal Alcohol Spectrum Disorder (FASD) is a complex set of developmental malformations, neurobehavioral anomalies and mental disabilities induced by exposing human embryos to alcohol during fetal development. Several experimental models and a series of developmental and biochemical approaches have established a strong link between FASD and reduced retinoic acid (RA) signaling. RA signaling is involved in the regulation of numerous developmental decisions from patterning of the anterior-posterior axis, starting at gastrulation, to the differentiation of specific cell types within developing organs, to adult tissue homeostasis. Being such an important regulatory signal during embryonic development, mutations or environmental perturbations that affect the level, timing or location of the RA signal can induce multiple and severe developmental malformations. The evidence connecting human syndromes to reduced RA signaling is presented here and the resulting phenotypes are compared to FASD. Available data suggest that competition between ethanol clearance and RA biosynthesis is a major etiological component in FASD.

Congenital heart defects in CHARGE: The molecular role of CHD7 and effects on cardiac phenotype and clinical outcomes

CHARGE syndrome is characterized by a pattern of congenital anomalies (Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth, Genital abnormalities, and Ear abnormalities). De novo mutations of chromodomain helicase DNA binding protein 7 (CHD7) are the primary cause of CHARGE syndrome. The clinical phenotype is highly variable including a wide spectrum of congenital heart defects. Here, we review the range of congenital heart defects and the molecular effects of CHD7 on cardiovascular development that lead to an over-representation of atrioventricular septal, conotruncal, and aortic arch defects in CHARGE syndrome. Further, we review the overlap of cardiovascular and noncardiovascular comorbidities present in CHARGE and their impact on the peri-operative morbidity and mortality in individuals with CHARGE syndrome.

CHARGE syndrome in nine patients from China

CHARGE syndrome (CS) is a multiple congenital anomalies condition with the majority of cases caused by dominant loss-of-function mutations of the CHD7 gene. It is clinically characterized by coloboma of the eyes, heart defects, choanal atresia, retardation of growth and/or development, genital and/or urinary anomalies and ear malformations associated with deafness and vestibular disorder(s). This case series reported nine molecularly confirmed Chinese CS patients from nine unrelated families in Hong Kong. Clinical phenotype and facial features of these nine Chinese CS patients together with four previously reported Chinese patients were reviewed. Typical presentations like coloboma and choanal atresia were not universally present. The prevalence of choanal atresia in these Chinese CS patients was found to be significantly lower than that in previous cohorts of other ethnic groups. This report highlighted the existence of phenotypic variation of CS among different ethnicities and suggested that a high index of suspicion is necessary for diagnosis of CS in Chinese patients.

Identification of a novel heterozygous missense mutation of SEMA3E (c.1327G>A; p. Ala443Thr) in a labor induced fetus with CHARGE syndrome

BACKGROUND

CHARGE syndrome is a complex multisystem genetic disease. We aimed to find the potential gene mutation in the labor induced fetus with CHARGE syndrome.

METHODS

Genomic DNA was extracted from the fetal thigh muscle tissue and the peripheral blood of his parents. The resulting exomes were sequenced using whole exome sequencing (WES) followed by the selection of the candidate causative mutation genes. The deleteriousness of the identified variants was predicted. Analysis of multiple alignment of protein sequences and protein conserved domains was performed by online software. Finally, Sanger sequencing was applied for validation of the identified variants in the WES.

RESULTS

After sequencing and bioinformatics filtering, a heterozygous missense mutation of SEMA3E (c.1327G>A; p. Ala443Thr) was found in the fetus, while the mutation was absent in his parents. Genotyping results showed that the mutation cosegregated fully with definite CHARGE phenotypes between the fetus and his parents. This change was located in the Sema superfamily and highly conserved across different species. Sanger validation result was consistent with the WES analysis.

CONCLUSION

Our investigations suggested that the heterozygous missense mutation of SEMA3E (c.1327G>A; p. Ala443Thr) may be a potential causal variant in the fetus with CHARGE syndrome.

Fetal cardiac abnormalities: Genetic etiologies to be considered

Congenital heart diseases are a common prenatal finding. The prenatal identification of an associated genetic syndrome or a major extracardiac anomaly helps to understand the etiopathogenic diagnosis. Besides, it also assesses the prognosis, management, and familial recurrence risk while strongly influences parental decision to choose termination of pregnancy or postnatal care. This review article describes the most common genetic diagnoses associated with a prenatal finding of a congenital heart disease and a suggested diagnostic process.

Auditory Skills following Cochlear Implantation in Children with the Charge Syndrome

OBJECTIVES

To assess the auditory outcomes and skills of pediatric cochlear implant (CI) users with the CHARGE syndrome. To determine the influence of inner ear malformations on the surgical procedure and speech understanding outcomes in this population.

STUDY DESIGN

Observational, retrospective study.

MATERIALS AND METHODS

Imaging, auditory testing, intraoperative findings, complications, and postoperative auditory skills and outcomes of pediatric CI users with CHARGE syndrome were recorded.

RESULTS

6 children (8 ears) were included, 5 of whom had prelingual deafness. Their mean age at implantation was 37 months. Six of the 8 ears presented cochlear malformation; the most frequent was hypoplasia type III. Intraoperatively, the transmastoid facial recess approach was used in 5 ears, and abnormalities of facial nerve anatomy were found in 5 ears. All electrode insertions were complete. All children were, to a varying degree, able to detect and identify sound. Verbalization skills were developed by 2 children, 1 of whom used oral language as his primary mode of communication.

CONCLUSIONS

Cochlear implantation performed by an experienced surgeon in patients with the CHARGE syndrome is a safe procedure with adequate treatment planning. All children had improved auditory skills although the improvement was variable.

Neonatal factors predictive for respiratory and gastro-intestinal morbidity after esophageal atresia repair

BACKGROUND

Esophageal atresia is a major congenital foregut anomaly. Affected patients often suffer from respiratory and gastro-intestinal morbidity. The objective of this study is to identify possible neonatal predictive factors contributing to a long-term complicated clinical course in patients after repair of esophageal atresia.

METHODS

A total of 93 patients born between 1993 and 2013, with esophageal atresia and surviving the neonatal period were included in this retrospective study. A complicated clinical course was defined as the occurrence of ≥1 of these complications: severe gastro-esophageal reflux, esophageal stricture requiring dilatations, need for tube feeding for >100 days, severe tracheomalacia, severe chronic respiratory disease and death. We used linear models with a binomial distribution to determine risk factors for gastro-intestinal or respiratory complicated evolution and a backward stepwise elimination procedure to reduce models until only significant variables remained in the model. Multinomial logistic regression was used to assess risk factors for different evolutions of complication. Model parameter estimates were used to calculate odds ratios for significant risk factors.

RESULTS

Fifty-seven patients (61%) had a complicated clinical course in the first year of life and 47 (51%) had a complicated evolution during years 1-6. In the first year, prematurity was a significant factor for complicated gastro-intestinal (OR 2.84) and respiratory evolution (OR 2.93). After 1 year, gastro-intestinal morbidity in childhood was associated with VACTERL association (OR 12.2) and a complicated first year (OR 36.1). Respiratory morbidity was associated with congenital heart disease (OR 12.9) and a complicated first year (OR 86.9). Multinomial logistic regression showed that prematurity (p = 0.018) and VACTERL association (p = 0.003) were significant factors of complications.

CONCLUSION

Prematurity is an important predictive factor for a complicated clinical course in early life. A complicated first year often predicts a complicated clinical course in childhood. These risk factors may be helpful in counseling of parents in the neonatal period.

A case of combined 21-hydroxylase deficiency and CHARGE syndrome featuring micropenis and cryptorchidism

Background

21‐hydroxylase deficiency (21‐OHD) is caused due to CYP21A2 gene variant. In males, the excess androgens produce varying degrees of penile enlargement and small testes. CHARGE syndrome (CS) has a broad spectrum of symptoms. In males, genital features such as micropenis and cryptorchidism are found in 48% of CS. There are no reports of patients with combined 21‐OHD and CS; therefore, it is unknown whether the external genitalia shows penile enlargement or micropenis with/without cryptorchidism.

Case

A boy, born at 37 weeks and 5 days of gestational age with no consanguineous marriage, was admitted to our hospital due to congenital cleft lip, cleft palate, micropenis, cryptorchidism, and a ventricular septal defect. He had severe hyponatremia and hyperkalemia on day 10. He was diagnosed to have 21‐OHD and CS. His external genitalia demonstrated both cryptorchidism and micropenis, but not penile enlargement.

Methods

DNA was extracted from peripheral leukocytes using standard procedures. Sanger sequence was performed in CYP21A2. Exome sequence was performed, and then, Sanger sequence was performed around variant in CHD7.

Results

Genetic screening for CYP21A2 gene was performed and compound heterozygous variants of c.293‐13A/C>G (IVS2‐13A/C>G) and c.518T>A (p.I172N) were detected in chromosome 6p21.3. His mother had been heterozygous variant of c.293‐13A/C>G, and his father had been heterozygous variant of c.518T>A. Simultaneously, a de novo splicing acceptor alteration in c.7165–4 A>G, in chromodomain helicase DNA binding protein‐7 (CHD7), located in chromosome 8q12 was detected, and the patient was diagnosed with 21‐OHD and CS.

Conclusion

Although these two disorders exhibit different modes of inheritance and their co‐morbidity is extremely rare, we encountered one male patient who suffered from both 21‐OHD and CS.

Oesophageal atresia

Oesophageal atresia (EA) is a congenital abnormality of the oesophagus that is caused by incomplete embryonic compartmentalization of the foregut. EA commonly occurs with a tracheo-oesophageal fistula (TEF). Associated birth defects or anomalies, such as VACTERL association, trisomy 18 or 21 and CHARGE syndrome, occur in the majority of patients born with EA. Although several studies have revealed signalling pathways and genes potentially involved in the development of EA, our understanding of the pathophysiology of EA lags behind the improvements in surgical and clinical care of patients born with this anomaly. EA is treated surgically to restore the oesophageal interruption and, if present, ligate and divide the TEF. Survival is now ~90% in those born with EA with severe associated anomalies and even higher in those born with EA alone. Despite these achievements, long-term gastrointestinal and respiratory complications and comorbidities in patients born with EA are common and lead to decreased quality of life. Oesophageal motility disorders are probably ubiquitous in patients after undergoing EA repair and often underlie these complications and comorbidities. The implementation of several new diagnostic and screening tools in clinical care, including high-resolution impedance manometry, pH-multichannel intraluminal impedance testing and disease-specific quality of life questionnaires now provide better insight into these problems and may contribute to better long-term outcomes in the future.

TGFβ-facilitated optic fissure fusion and the role of bone morphogenetic protein antagonism

The optic fissure is a transient gap in the developing vertebrate eye, which must be closed as development proceeds. A persisting optic fissure, coloboma, is a major cause for blindness in children. Although many genes have been linked to coloboma, the process of optic fissure fusion is still little appreciated, especially on a molecular level. We identified a coloboma in mice with a targeted inactivation of transforming growth factor β2 (TGFβ2). Notably, here the optic fissure margins must have touched, however failed to fuse. Transcriptomic analyses indicated an effect on remodelling of the extracellular matrix (ECM) as an underlying mechanism. TGFβ signalling is well known for its effect on ECM remodelling, but it is at the same time often inhibited by bone morphogenetic protein (BMP) signalling. Notably, we also identified two BMP antagonists among the downregulated genes. For further functional analyses we made use of zebrafish, in which we found TGFβ ligands expressed in the developing eye, and the ligand binding receptor in the optic fissure margins where we also found active TGFβ signalling and, notably, also gremlin 2b (grem2b) and follistatin a (fsta), homologues of the regulated BMP antagonists. We hypothesized that TGFβ is locally inducing expression of BMP antagonists within the margins to relieve the inhibition from its regulatory capacity regarding ECM remodelling. We tested our hypothesis and found that induced BMP expression is sufficient to inhibit optic fissure fusion, resulting in coloboma. Our findings can likely be applied also to other fusion processes, especially when TGFβ signalling or BMP antagonism is involved, as in fusion processes during orofacial development.