Adams-Oliver syndrome associated with cardiovascular malformations

Investigation of Genetic Causes in Patients with Congenital Heart Disease in Qatar: Findings from the Sidra Cardiac Registry

Congenital heart disease (CHD) is one of the most common forms of birth defects worldwide, with a prevalence of 1–2% in newborns. CHD is a multifactorial disease partially caused by genetic defects, including chromosomal abnormalities and single gene mutations. Here, we describe the Sidra Cardiac Registry, which includes 52 families and a total of 178 individuals, and investigate the genetic etiology of CHD in Qatar. We reviewed the results of genetic tests conducted in patients as part of their clinical evaluation, including chromosomal testing. We also performed whole exome sequencing (WES) to identify potential causative variants. Sixteen patients with CHD had chromosomal abnormalities that explained their complex CHD phenotype, including six patients with trisomy 21. Moreover, using exome analysis, we identified potential CHD variants in 24 patients, revealing 65 potential variants in 56 genes. Four variants were classified as pathogenic/likely pathogenic based on the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) classification; these variants were detected in four patients. This study sheds light on several potential genetic variants contributing to the development of CHD. Additional functional studies are needed to better understand the role of the identified variants in the pathogenesis of CHD.

Functional genomics and gene-environment interaction highlight the complexity of congenital heart disease caused by Notch pathway variants

Congenital heart disease (CHD) is the most common birth defect and brings with it significant mortality and morbidity. The application of exome and genome sequencing has greatly improved the rate of genetic diagnosis for CHD but the cause in the majority of cases remains uncertain. It is clear that genetics, as well as environmental influences, play roles in the aetiology of CHD. Here we address both these aspects of causation with respect to the Notch signalling pathway. In our CHD cohort, variants in core Notch pathway genes account for 20% of those that cause disease, a rate that did not increase with the inclusion of genes of the broader Notch pathway and its regulators. This is reinforced by case-control burden analysis where variants in Notch pathway genes are enriched in CHD patients. This enrichment is due to variation in NOTCH1. Functional analysis of some novel missense NOTCH1 and DLL4 variants in cultured cells demonstrate reduced signalling activity, allowing variant reclassification. Although loss-of-function variants in DLL4 are known to cause Adams-Oliver syndrome, this is the first report of a hypomorphic DLL4 allele as a cause of isolated CHD. Finally, we demonstrate a gene-environment interaction in mouse embryos between Notch1 heterozygosity and low oxygen- or anti-arrhythmic drug-induced gestational hypoxia, resulting in an increased incidence of heart defects. This implies that exposure to environmental insults such as hypoxia could explain variable expressivity and penetrance of observed CHD in families carrying Notch pathway variants.

Familial aggregation of "apple peel" intestinal atresia and cardiac left-sided obstructive lesions: A possible causal relationship with NOTCH1 gene mutations

"Apple peel" intestinal atresia is a rare form of small bowel atresia, in which the duodenum or proximal jejunum ends in a blind pouch and the distal small bowel wraps around its vascular supply, in a spiral resembling an apple peel. The etiology of "apple peel" intestinal atresia is presently unknown, although a congenital or acquired intestinal vascular accident can have a role in the pathogenesis. We report a family in which the proband affected by "apple peel" intestinal atresia, had a sibling (an interrupted pregnancy), and a paternal cousin with cardiac left-sided obstructive lesions. Molecular testing for NOTCH1 gene was carried out in the proband, because pathogenic mutations in this gene have been associated with familial and sporadic cardiac left-sided obstructive lesions and vascular anomalies, both isolated or within the spectrum of the Adams-Oliver syndrome (AOS). The heterozygous c.2734C>T (p.Arg912Trp) NOTCH1 variant was found in the proband with "apple peel" intestinal atresia and in his father. This result argues for a possible causal relationship between NOTCH1 gene mutations and some forms of intestinal defects, through a vascular mechanism. The spectrum of NOTCH1-associated malformations is widened. Genetic counseling should take into account intrafamilial variable clinical expression and incomplete penetrance.

A practical approach to the evaluation and treatment of an infant with aplasia cutis congenita

Aplasia cutis congenita (ACC) is a term describing absence of skin at birth. ACC is a rare cutaneous finding, often noted with no other physical abnormalities. The etiology of ACC varies, and there are likely several causes for its development. ACC can be located anywhere on the body. Its clinical appearance and location can alert the clinician to other potential abnormalities and associations. This discussion covers the diagnosis of ACC and its subtypes and associations in order to provide a pragmatic, clinically relevant and patient-centered approach to evaluation and treatment.

Adams-Olıver syndrome: A case report

Background: Adams-Oliver Syndrome has been described by Adams and Oliver in 1945. Original definition, along with aplasia cutis congenital syndrome and limb defects, has neurological and cardiological problems. In the first description, genetic defect passes variable autosomal dominant pattern. Afterwards the autosomal recessive and sporadic cases were published. Case Report: 11-year old male patient complained of mobile teeth admitted to our clinic. He was noted to have characteristic view with distal-phalanx and nail hypoplasia of his hand and feet with occipital scalp defect. We consulted to genetics because of these findings and learned that he has the Adams-Oliver Syndrome. The patient has some orofacial manifestations including high-narrow palate, fissured tongue, crowding, dysmorphic facial features, facial asymmetry, deep-philtrum, delayed eruption, class III malocclusion. The extraction of mobile deciduous teeth, restoration of caries and also oral hygiene motivation was made. Then, the patient was referred to orthodontics. Conclusions: Adams-Oliver syndrome represents are rare congenital alteration, insufficiently documented in scientific literature. This shows the need to document news cases.

Haploinsufficiency of the NOTCH1 Receptor as a Cause of Adams-Oliver Syndrome With Variable Cardiac Anomalies

BACKGROUND

Adams-Oliver syndrome (AOS) is a rare disorder characterized by congenital limb defects and scalp cutis aplasia. In a proportion of cases, notable cardiac involvement is also apparent. Despite recent advances in the understanding of the genetic basis of AOS, for the majority of affected subjects, the underlying molecular defect remains unresolved. This study aimed to identify novel genetic determinants of AOS.

METHODS AND RESULTS

Whole-exome sequencing was performed for 12 probands, each with a clinical diagnosis of AOS. Analyses led to the identification of novel heterozygous truncating NOTCH1 mutations (c.1649dupA and c.6049_6050delTC) in 2 kindreds in which AOS was segregating as an autosomal dominant trait. Screening a cohort of 52 unrelated AOS subjects, we detected 8 additional unique NOTCH1 mutations, including 3 de novo amino acid substitutions, all within the ligand-binding domain. Congenital heart anomalies were noted in 47% (8/17) of NOTCH1-positive probands and affected family members. In leukocyte-derived RNA from subjects harboring NOTCH1 extracellular domain mutations, we observed significant reduction of NOTCH1 expression, suggesting instability and degradation of mutant mRNA transcripts by the cellular machinery. Transient transfection of mutagenized NOTCH1 missense constructs also revealed significant reduction in gene expression. Mutant NOTCH1 expression was associated with downregulation of the Notch target genes HEY1 and HES1, indicating that NOTCH1-related AOS arises through dysregulation of the Notch signaling pathway.

CONCLUSIONS

These findings highlight a key role for NOTCH1 across a range of developmental anomalies that include cardiac defects and implicate NOTCH1 haploinsufficiency as a likely molecular mechanism for this group of disorders.

Mutations in NOTCH1 cause Adams-Oliver syndrome

Notch signaling determines and reinforces cell fate in bilaterally symmetric multicellular eukaryotes. Despite the involvement of Notch in many key developmental systems, human mutations in Notch signaling components have mainly been described in disorders with vascular and bone effects. Here, we report five heterozygous NOTCH1 variants in unrelated individuals with Adams-Oliver syndrome (AOS), a rare disease with major features of aplasia cutis of the scalp and terminal transverse limb defects. Using whole-genome sequencing in a cohort of 11 families lacking mutations in the four genes with known roles in AOS pathology (ARHGAP31, RBPJ, DOCK6, and EOGT), we found a heterozygous de novo 85 kb deletion spanning the NOTCH1 5' region and three coding variants (c.1285T>C [p.Cys429Arg], c.4487G>A [p.Cys1496Tyr], and c.5965G>A [p.Asp1989Asn]), two of which are de novo, in four unrelated probands. In a fifth family, we identified a heterozygous canonical splice-site variant (c.743-1 G>T) in an affected father and daughter. These variants were not present in 5,077 in-house control genomes or in public databases. In keeping with the prominent developmental role described for Notch1 in mouse vasculature, we observed cardiac and multiple vascular defects in four of the five families. We propose that the limb and scalp defects might also be due to a vasculopathy in NOTCH1-related AOS. Our results suggest that mutations in NOTCH1 are the most common cause of AOS and add to a growing list of human diseases that have a vascular and/or bony component and are caused by alterations in the Notch signaling pathway.

Vascular limb defects and maternal age

BACKGROUND

The prenatal diagnosis procedure chorionic villus sampling is associated with increased risk of vascular disruption limb defects. Some studies have suggested that these defects are more common among infants born to women 35 years and older while other studies have shown a correlation with younger mothers.

METHODS

All infants with vascular disruption defects were identified in the Active Malformations Surveillance Program at Brigham and Women's Hospital in the years 1972-1974, 1979-2011. We compared the rate of occurrence of infants with vascular limb defects among women in theses age groups: ≤19, 20 to 34, and ≥35 years to the rate of occurrence of infants with preaxial polydactyly, adjusting for race. Infants with an identifiable cause of their defects were excluded.

RESULTS

106 infants with vascular disruption defects and 67 with preaxial polydactyly were identified. Seventeen percent of the infants with vascular disruption defects and 25% of the infants with preaxial polydactyly were born to women 35 and older (p = 0.23). In contrast, 16% of the infants with vascular disruption defects were born to young mothers (≤19 years) compared with 6.0% of the mothers of infants with preaxial polydactyly (adjusted odds ratio vs. 35+ years = 5.3, 95% confidence interval 1.4-21, p = 0.017).

CONCLUSION

Women 35 years old or older did not have increased risk for having a child with vascular disruption defects, but these defects were more common among infants of young (≤19) mothers, compared with the preaxial polydactyly group.

Unique variant of Adams-Oliver syndrome with dilated cardiomyopathy and heart block

Reported herein is the case of a 2-year-old boy with Adams-Oliver syndrome who presented with dilated cardiomyopathy and complete atrioventricular block. The patient had aplasia cutis congenita with partial aplasia of the skull bones, and terminal transverse limb malformations characteristic of the disease. Although congenital cardiac malformations may be associated with the syndrome, dilated cardiomyopathy has not been previously reported to be associated with the syndrome.

Expanding the phenotype of cardiovascular malformations in Adams-Oliver syndrome

We describe a newborn with a phenotype consistent with Adams-Oliver syndrome and truncus arteriosus. Although cardiovascular malformations associated with this syndrome have been previously published in the literature, this is the first description of truncus arteriosus in a patient with Adams-Oliver syndrome. We review other reports of Adams-Oliver syndrome previously described with cardiovascular malformations, consider possible genetic and embryologic mechanisms, and emphasize the need for cardiology consultation when a diagnosis of Adams-Oliver syndrome is suspected in the differential diagnosis.

Dilemmas and challenges in the management of a neonate with Adams-Oliver syndrome with infected giant aplasia cutis lesion and exsanguination: a case-based update

BACKGROUND

Aplasia cutis is a rare developmental anomaly usually involving the calvarium, associated with a variable extent of defective formation of the scalp. Adams-Oliver syndrome is a condition mainly characterized by the congenital absence of skin, known as "aplasia cutis" which is usually limited to the vertex scalp and transverse limb defects.

CASE REPORT

A 17-day-old term female neonate was referred to us with an infected scalp lesion of the vertex. The lesion which is about 10 × 9 cm had signs of infection with necrotic eschar. We started the neonate on systemic parenteral antibiotics with local dressings. On day 3 of conservative management, the neonate had exsanguination due to bleeding from the midline with severe hemodynamic compromise requiring cardiopulmonary resuscitation. After controlling the bleeding with local tamponade and resuscitating the child, she was taken for early surgery. Debridement and bipedicled rotation flap of the scalp to cover the raw area was performed. On day 18, the flap started showing signs of necrosis. The neonate was taken up for debridement, and subsequently, maternal allograft of split-thickness skin was placed as a temporary wound cover. Meanwhile, the wound showed progressive epithelialization. At 1 year, the patient continued to have a non-healing area, which was later successfully covered with a split-thickness skin graft. We plan to revaluate the need for cranioplasty at around 3-4 years of age.

DISCUSSION

We discuss the dilemmas and challenges involved in the successful management of a neonate with Adams-Oliver syndrome with infected aplasia cutis and an episode of life-threatening exsanguination.

CONCLUSION

Aplasia cutis is a rare developmental anomaly usually involving the calvarium, associated with defective formation of the scalp to a varying extent and severity, requiring various timely strategies.

Inclusion and exclusion criteria for malformations in newborn infants exposed to potential teratogens

BACKGROUND

The surveillance of newborn infants exposed to potential teratogens often relies on the findings in routine physicians' examinations to identify malformations. Exposed newborn infants can have a wide variety of physical features, including malformations, birth marks, positional deformities, and minor anomalies. The routine physician's findings are not standardized. Some physicians record a wide variety of physical features and others do not. The purpose of this study was to develop criteria and definitions for identifying malformations and for identifying the more common and less severe physical features that would be excluded as not being malformations.

METHODS

The physical features recorded by the examining pediatricians were obtained from a review of the medical records of a consecutive sample of 1000 liveborn and stillborn infants and elective terminations for fetal anomalies.

RESULTS

A malformation, defined as a structural abnormality with surgical, medical or cosmetic importance, was present in 18 (2.8%) of the infants; 222 other recorded features were identified and excluded: malformations attributed to dominant or recessive genes (4) or chromosome abnormalities (6), minor anomalies and normal variations (65), birth marks (110), positional deformities (6), prematurity-related features (5), physiologic findings (4) and findings identified by prenatal ultrasound (but not by the examining pediatrician) (20), functional abnormalities (1) and findings in newborn screening (1).

CONCLUSIONS

Investigators should establish, in advance, the exclusion criteria to be used in programs, such as malformation surveillance programs or pregnancy registries, whose findings are based on a review of the routine examinations in medical records. It is essential that the same criteria be used in evaluating the drug-exposed and the unexposed comparison group.

[Adams-Oliver syndrome: a case with minimal expression]

Adams-Oliver syndrome is a rare congenital anomaly characterized by aplasia cutis congenita (ACC) and variable degrees of terminal transverse limb defects. We report on a neonatal case with the sporadic form of the disease with minimal expression, illustrating the wide spectrum of clinical expression in Adams-Oliver syndrome. We also review the literature and highlight the different pathogenetic hypotheses of this syndrome.

Unicuspid aortic valve, hand anomalies: a heart-hand syndrome

Embryonic heart and limb development are closely related with >100 known inherited disorders affecting both. Common limb defects include duplication, deficiencies, and hypoplasia. Ventricular septal defects and atrial septal defects are the commonest associated cardiac conditions. A positive association exists between heart defects and limb disorders when these disorders are analyzed separately. Closer associations exist between heart defects and upper limb defects compared with lower limb defects. The majority of limb defects occur in the more distal parts of the affected limb. Genes expressed in both the heart and limb development include TGF-beta, BMP4, Msx transcription factor, HAND gene, retinoic acid receptor, and sonic hedgehog gene. Radial ray-heart syndromes are better described than ulnar ray-hand syndromes. There is significant variability of malformations. Partial phenocopies that are not genetically linked are well documented. An appreciation of ulnar anomalies should always provoke an evaluation of the heart for potential abnormalities. Although heart-hand syndromes are rare, valvular abnormalities and aortic aneurysms can lead to significant complications unless identified in time. The presence of radial or ulnar ray anomalies merit a detailed cardiac examination and a low threshold for cardiac imaging.

The spectra of clinical phenotypes in aplasia cutis congenita and terminal transverse limb defects

The combination of aplasia cutis congenita (ACC) and terminal transverse limb defects (TTLD) is often referred to as the eponymous Adams-Oliver syndrome (AOS). The molecular basis of this disorder remains unknown, although the common occurrence of cardiac and vascular anomalies suggests a primary defect of vasculogenesis. Through the description of three previously unreported affected individuals, ascertained through the Adams-Oliver Syndrome European Consortium, we illustrate the phenotypic variability characteristically observed within extended families with AOS. Taken in combination with a detailed review of the available literature, we provide evidence for distinct clinical entities within the ACC/TTLD spectrum, which may reflect genetic heterogeneity within this spectrum of disorders.

Adams-Oliver syndrome: further evidence of an autosomal recessive variant

Adams-Oliver syndrome is characterized by aplasia cutis congenita and variable degrees of terminal transverse limb defects. Other associated anomalies were described in the syndrome. Most described cases follow an autosomal dominant pattern of inheritance. Sporadic and autosomal recessive cases, however, were reported. In this study, we report on three Egyptian patients with Adams-Oliver syndrome from three different families. The parents were normal and consanguineous in all three families. There was history of similarly affected sibs for two cases. These findings denote autosomal recessive inheritance. The reported cases had typical skull and limb anomalies with cutis marmorata telangiectatica congenita. We observed additional rare manifestations in the form of microcephaly, psychomotor retardation, epilepsy, eye anomalies and atrophic skin lesions. MRI of the brain in one of the studied cases revealed retrocerebellar cyst and mild asymmetrical cerebellar hypoplasia, which to our knowledge, were not previously reported in Adams-Oliver syndrome. The results of this study provide further evidence of clinical and genetic heterogeneity and support the presence of autosomal recessive variant of Adams-Oliver syndrome.

Adams-Oliver syndrome: clinical description of a four-generation family and exclusion of five candidate genes

We present a Belgian Adams-Oliver syndrome (AOS) family with 10 affected individuals over four generations, of which six were available for this study. Clinical symptoms observed in these patients were very variable as previously reported in other families and included large areas of alopecia on the vertex of the skull and serious limb reduction defects with agenesis of all toes of one foot. To identify the disease-causing gene, we sequenced the MSX1, CART1, P63 (P73L), RUNX2, and HOXD13 genes in this family and nine previously reported families, but no disease-causing mutations were found. Further investigation is ongoing in these families in order to identify the genetic cause of AOS.

Association of Adams-Oliver syndrome with pulmonary arterio-venous malformation in the same family: A further support to the vascular hypothesis

Adams-Oliver syndrome (AOS) is a rare disease characterized by congenital scalp defects, terminal transverse limb defects and cutis marmorata telangiectatica. A significant incidence of cardiac and vascular malformations has been reported, leading to the hypothesis of a vascular defect early involved in the pathogenesis. We report two members of the same family with previously diagnosed AOS based on clinical phenotype and later recognized to have pulmonary arterio-venous malformation (PAVM). None of the subjects fulfilled current diagnostic criteria of hereditary hemorrhagic telangiectasia, which is the most common cause of PAVM. The occurrence of PAVM in AOS lends support to the hypothesis that endothelial specific abnormalities could be a patho-physiological mechanism in its development. Therefore, the role of screening for PAVM in clinical management of subjects with AOS should deserve further studies.

A case of Adams-Oliver syndrome with associated brain and pulmonary involvement: Further evidence of vascular pathology?

We report on a case of Adams-Oliver syndrome (AOS) with typical skin and limb defects along with the unique findings of pulmonary hypertension and central nervous system (CNS) involvement. Adams-Oliver syndrome has a wide spectrum of physical anomalies ranging from characteristic aplasia cutis congenita (ACC), transverse limb defects, and cutis marmorata telangiectica to extensive lethal anomalies. While pulmonary hypertension is usually not associated with AOS, the abnormal endothelial regulation of vascular tone seen in the pulmonary vasculature may enhance current pathophysiologic concepts of vascular abnormalities in AOS. There is accumulating evidence of significant CNS defects in AOS. This infant had hypoplastic corpus callosum and focal findings in the periventricular white matter. Evaluation for pulmonary hypertension and CNS anomalies in patients suspected to have AOS, can help identify those who are at risk for acute morbidities and associated developmental delays.

Abnormal pericyte recruitment as a cause for pulmonary hypertension in Adams-Oliver syndrome

Adams-Oliver syndrome (AOS) consists of congenital scalp defects with variable limb defects of unknown pathogenesis. We report on two children with AOS plus additional features including intrauterine growth retardation (IUGR), cutis marmorata telangiectatica congenita (CMTC), pulmonary hypertension (PH), intracranial densities shown in one case to be sites of active bleeding and osteopenia. Autopsy in one case revealed defective vascular smooth muscle cell/pericyte coverage of the vasculature associated with two blood vessel abnormalities. Pericyte absence correlated with vessel dilatation while hyperproliferation of pericytes correlated with vessel stenosis. These findings suggest a unifying pathogenic mechanism for the abnormalities seen in AOS. These and previously reported cases establish that a subset of AOS patients is at high risk for PH.

Clinical and molecular analysis of nine families with Adams-Oliver syndrome

Adams-Oliver syndrome (AOS) is defined by the combination of limb abnormalities and scalp defects, often accompanied by skull ossification defects. We studied nine families affected with AOS, eight of which have not been clinically described before. In our patients, scalp abnormalities were most often found, followed by limb and skull defects. The most common limb abnormalities appeared to be brachydactyly, syndactyly of toes 2 and 3 and hypoplastic toenails. Additional features observed were cutis marmorata telangiectatica congenita, cryptorchidism and cardiac abnormalities. In an attempt to identify the disease-causing mutations in our families, we selected two genes, ALX4 and MSX2, which were considered serious candidates based on their known function in skull and limb development. Mutation analysis of both genes, performed by direct sequencing, identified several polymorphisms, but no disease-causing mutations. Therefore, we can conclude that the AOS in our set of patients is not caused by mutations in ALX4 or MSX2.

Autosomal recessive type of Adams-Oliver syndrome: prenatal diagnosis

We report on three pregnancies complicated by Adams-Oliver syndrome in a consanguineous Turkish couple. Two cases were correctly diagnosed prenatally at 22+3 and 13+0 weeks gestation following the first case of Adams-Oliver syndrome in which severe anomalies of the extremities were observed at 26+5 weeks' gestation. In this first case, the diagnosis of Adams-Oliver syndrome was made following termination of pregnancy at 27+2 weeks' gestation. In all three cases, autopsy was performed. All fetuses showed anomalies of the extremities, aplasia cutis and symmetric defects of the skull, with bone being replaced by collagenous tissue. Although there have been numerous cases of the postnatal diagnosis of Adams-Oliver syndrome following termination of pregnancy, this is the first description of the prenatal diagnosis of this disorder.

Hypoplastic left heart and postaxial polydactyly

Two siblings are presented with hypoplastic left heart syndrome and symmetrical postaxial polydactyly affecting upper and lower limbs. This association has not been previously documented. This appears to represent a newly recognized syndrome. The inheritance is likely to be autosomal recessive, but other inheritance patterns cannot be excluded at present.

Congenital heart defects in Kabuki syndrome

Kabuki makeup (Niikawa-Kuroki) syndrome (KS) is characterized by distinct facial anomalies, mental retardation, congenital heart defect (CHD), and skeletal malformations. In the present study we analyze cardiac characteristics and differences in sex prevalence of specific CHDs in our series of patients with KS and review published reports from the literature. Between January 1992 and February 2000, 60 patients (37 males and 23 females) with KS underwent phenotypic and cardiac evaluations at our hospital. CHD was diagnosed in 35 (58%) of our patients. Aortic coarctation (COA) (23%), atrial septal defect (ASD) (20%), and ventricular septal defect (VSD) (17%) were the most frequent CHDs in our series and in previous reports from the literature. Male preponderance was noted in patients with COA. In conclusion, CHD is a cardinal feature of KS. There is an overlap between cardiac malformations of KS and those of Turner syndrome. Male preponderance in patients with KS and COA supports the hypothesis that genes located on the X chromosome may be involved in determining KS in some patients. The high prevalence of CHD prompts accurate re-examination of patients evaluated by pediatric cardiologists in order to identify mild and still unrecognized cases of KS.

Transverse limb defects associated with aorto-pulmonary vascular abnormalities: vascular disruption sequence or atypical presentation of Adams-Oliver syndrome?

We report a patient with terminal transverse limb defects associated with persistent primitive aorto-pulmonary vascular connections leading to supra-systemic pulmonary artery pressure. It is likely that this patient represents a vascular disruption sequence or as an alternative a form of Adams-Oliver syndrome. These assumptions are based only on the association of vascular abnormalities as an emerging and apparently important association with transverse limb defects despite the absence of aplasia cutis congenita commonly associated with Adams-Oliver syndrome.