A lethal multiple pterygium syndrome with apparent X-linked recessive inheritance

Arthrogryposis is a descriptive term, not a specific disease entity: Escobar Syndrome is an example

BACKGROUND

Children born with multiple congenital contractures have been almost always given the diagnosis of arthrogryposis multiplex congenita. Arthrogryposis is a descriptive term, not a specific disease entity. A heterogeneous group of conditions associated with multiple congenital joint contractures (mostly syndromic) should be considered.

METHODS

The records of seven children (four boys and three girls aged 6 months - 11 years) of different ethnic origins have been included in this study. The constellation of specific craniofacial dysmorphic features, spine malformation complex, and appendicular skeletal abnormalities in addition to camptodactyly, talipes equinovarus and rocker-bottom feet were a cluster of malformation complex encountered in our patients. Via comprehensive clinical and imaging study (3D reconstruction CT scan), definite diagnosis of Escobar Syndrome has been approached.

RESULTS

The clinical and imaging phenotype was the key factor towards etiological understanding, treatment and genotype confirmation. We identified compound heterozygous mutations (c.459dupA [p.Val154Serfs*24] and c.794T>G [p.Leu265Serfs*24] of the CHRNG gene in four patients. Bilateral flexion contractures of the knees have been treated by using Iliazarov external fixator. Simultaneous corrections of scoliosis have been achieved by applying either dual traditional growing rods or single growing rods.

CONCLUSIONS

The clinical and radiological phenotypic characterizations are the fundamental tool in differentiating Escobar from other forms of multiple contractures. The aim of this study are three folds, firstly to demonstrate the importance of detecting the etiological understanding in children presented with multiple contractures, secondly to refute the general conception among the vast majority of pediatricians and orthopedic surgeons that arthrogryposis multiplex is a diagnostic entity. And thirdly, we were able to detect severe spine deformity via 3D reconstruction CT scan, namely unsegmented posterior spinal bar.

Lethal multiple pterygium syndrome in a newborn, a case report

Lethal multiple pterygium syndrome is a very rare genetic disorder. The manifestations of this condition include growth deficiency of the fetus, craniofacial anomalies, joint contracture, and skin webbing (pterygia). This disorder is fatal before birth or shortly after birth. We reported a case of lethal multiple pterygium syndrome with multiple anomalies including pterygia involving the axilla, bilateral antecubital fossa, and groin. Arthrogryposis involving multiple lower and upper extremities joints. Cleft palate, microstomia and limitation of mouth opening, webbed neck, asymmetric small and narrow chest, ambiguous genitalia, depressed and wide nasal bridge, antemongoloid slant, low-set, malformed, and posteriorly rotated ears, pterygia, syndactyly and camptodactyly of hands and rocket bottom feet. LMPS is a congenital genetic disease with multiple anomalies that is fatal in the second and third trimesters of pregnancy or shortly after birth. With genetic testing and counseling, it can be prevented from recurring in subsequent pregnancies.

Case Report: Early diagnosis of lethal multiple pterygium syndrome with micrognathia: Two novel mutations in the CHRND gene

Lethal multiple pterygium syndrome (LMPS) is a rare disease with genetic and phenotypic heterogeneity and is inherited in an autosomal recessive (AR) pattern. Here, we have presented clinically significant results describing two novel mutations of CHRND gene: NM_000751.2: c.1006C>T p.(Arg336Ter) and NM_000751.2:c.973_975delGTG p.(Val325del), and measurement of the facial angle for determining micrognathia by prenatal diagnosis in the first trimester of pregnancy for a Lethal multiple pterygium syndrome case. In conclusion, this report complements the spectrum of genetic variants and phenotype of Lethal multiple pterygium syndrome and provides reliable recommendation for the counseling of future pregnancies in families with the disease.

Case Report: Novel compound heterozygous variants in CHRNA1 gene leading to lethal multiple pterygium syndrome: A case report

Background: Lethal multiple pterygium syndrome (LMPS) is a rare autosomal recessive inherited disorder typically characterized by intrauterine growth retardation, multiple pterygia, and flexion contractures.

Case presentation: We herein report a Chinese case with a history of three adverse pregnancies demonstrating the same ultrasonic phenotypes, including increased nuchal translucency, edema, fetal neck cystoma, reduced movement, joint contractures, and other congenital features. Whole-exome sequencing (WES) revealed novel compound heterozygous variants in the CHRNA1 gene NM_000079.4: c.[1128delG (p.Pro377LeufsTer10)]; [505T>C (p.Trp169Arg)] in the recruited individual, and subsequent familial segregation showed that both parents transmitted their respective mutation.

Conclusion: For the first time, we identified an association between the CHRNA1 gene and the recurrent lethal multiple pterygium syndrome (LMPS) in a Chinese family. This finding may also enrich the mutation spectrum of the CHRNA1 gene and promote the applications of WES technology in etiologic diagnosis of ultrasound anomalies in prenatal examination.

Cardiac anomalies associated with Escobar syndrome: A case report and a review of the literature

RATIONALE

Escobar syndrome (ES) is an autosomal recessive disorder. It is highly characterized by facial abnormalities, congenital diaphragmatic muscle weakness, myasthenic-like features, and skin pterygiums on multiple body legions. ES is a rare condition associated with many external and internal abnormalities. The internal malformations described in ES affect many organs including the heart, lungs, esophagus, liver, spleen, and intestine. The purpose of this paper is to explore the cardiac manifestations associated with ES.

PATIENT CONCERNS

A 3.5-year-old girl, who was born for double first cousins, was admitted to the hospital for neuromuscular evaluation of multiple congenital contractures.

DIAGNOSIS

The girl was diagnosed with ES and isolated dextrocardia which is a rare cardiac manifestation. However, to the best of our knowledge, no similar cases have been reported to date, and this case is thus believed to be very rare.

INTERVENTIONS

The patient underwent an operative intervention to correct the bilateral fixed flexion deformity at her knees which was related to the posterior bilateral fibrotic bands/pterygia.

OUTCOMES

Post-operatively, complete knee extension was obtained, the patient was fitted with a cast and extension night splint. She was discharged alive and had no complications. The patient was followed regularly in the orthopedic clinic and had periodic physiotherapy sessions.

CONCLUSIONS

ES and isolated dextrocardia concurrence in the presented case resulted from different pathogenic mechanisms. Our findings suggest that ES might be caused by dysfunction in the acetylcholine receptor throughout fetal life, which may have affected muscle strength and movement. Other cardiac conditions include hypoplastic left-sided heart, Hypertrophic cardiomyopathy, patent ductus arteriosus, and heterotaxia.

A recurrent pathogenic variant in TPM2 reveals further phenotypic and genetic heterogeneity in multiple pterygium syndrome-related disorders

Multiple pterygium syndrome (MPS) disorders are a phenotypically and genetically heterogeneous group of conditions characterized by multiple joint contractures (arthrogryposis), pterygia (joint webbing) and other developmental defects. MPS is most frequently inherited in an autosomal recessive fashion but X-linked and autosomal dominant forms also occur. Advances in genomic technologies have identified many genetic causes of MPS-related disorders and genetic diagnosis requires large targeted next generation sequencing gene panels or genome-wide sequencing approaches. Using the Illumina TruSightOne clinical exome assay, we identified a recurrent heterozygous missense substitution in TPM2 (encoding beta tropomyosin) in three unrelated individuals. This was confirmed to have arisen as a de novo event in the two patients with parental samples. TPM2 mutations have previously been described in association with a variety of dominantly inherited neuromuscular phenotypes including nemaline myopathy, congenital fibre-type disproportion, distal arthrogryposis and trismus pseudocamptodactyly, and in a patient with autosomal recessive Escobar syndrome and a nemaline myopathy. The three cases reported here had overlapping but variable features. Our findings expand the range of TMP2-related phenotypes and indicate that de novo TMP2 mutations should be considered in isolated cases of MPS-related conditions.

Pena-Shokeir syndrome: current management strategies and palliative care

Pena-Shokeir syndrome (PSS) type 1, also known as fetal akinesia deformation sequence, is a rare genetic syndrome that almost always results in intrauterine or early neonatal death. It is characterized by markedly decreased fetal movements, intrauterine growth restriction, joint contractures, short umbilical cord, and features of pulmonary hypoplasia. Antenatal diagnosis can be difficult. Ultrasound features are varied and may overlap with those of Trisomy 18. The poor prognosis of PSS is due to pulmonary hypoplasia, which is an important feature that distinguishes PSS from arthrogryposis multiplex congenital without pulmonary hypoplasia, which has a better prognosis. If diagnosed in the antenatal period, a late termination of pregnancy can be considered following ethical discussion (if the law allows). In most cases, a diagnosis is only made in the neonatal period. Parents of a baby affected with PSS require detailed counseling that includes information on the imprecise recurrence risks and a plan for subsequent pregnancies.

Truncating CHRNG mutations associated with interfamilial variability of the severity of the Escobar variant of multiple pterygium syndrome

Background

In humans, muscle-specific nicotinergic acetylcholine receptor (AChR) is a transmembrane protein with five different subunits, coded by CHRNA1, CHRNB, CHRND and CHRNG/CHRNE. The gamma subunit of AChR encoded by CHRNG is expressed during early foetal development, whereas in the adult, the γ subunit is replaced by a ε subunit. Mutations in the CHRNG encoding the embryonal acetylcholine receptor may cause the non-lethal Escobar variant (EVMPS) and lethal form (LMPS) of multiple pterygium syndrome. The MPS is a condition characterised by prenatal growth failure with pterygium and akinesia leading to muscle weakness and severe congenital contractures, as well as scoliosis.

Results

Our whole exome sequencing studies have identified one novel and two previously reported homozygous mutations in CHRNG in three families affected by non-lethal EVMPS. The mutations consist of deletion of two nucleotides, cause a frameshift predicted to result in premature termination of the foetally expressed gamma subunit of the AChR.

Conclusions

Our data suggest that severity of the phenotype varies significantly both within and between families with MPS and that there is no apparent correlation between mutation position and clinical phenotype. Although individuals with CHRNG mutations can survive, there is an increased frequency of abortions and stillbirth in their families. Furthermore, genetic background and environmental modifiers might be of significance for decisiveness of the lethal spectrum, rather than the state of the mutation per se. Detailed clinical examination of our patients further indicates the changing phenotype from infancy to childhood.

Orthopaedic manifestations and treatment outcome of two siblings with Escobar syndrome and homozygous mutations in the CHRNG gene

Escobar syndrome is a nonlethal subtype of multiple pterygium syndromes, characterized by webbing across the joints, congenital joint contracture, facial dysmorphism and a variety of other congenital anomalies. We report orthopaedic manifestation and the treatment outcome of two siblings with Escobar syndrome caused by homozygous mutations of the CHRNG gene.

MuSK: a new target for lethal fetal akinesia deformation sequence (FADS)

BACKGROUND

Fetal akinesia deformation sequence syndrome (FADS, OMIM 208150) is characterised by decreased fetal movement (fetal akinesia) as well as intrauterine growth restriction, arthrogryposis, and developmental anomalies (eg, cystic hygroma, pulmonary hypoplasia, cleft palate, and cryptorchidism). Mutations in components of the acetylcholine receptor (AChR) pathway have previously been associated with FADS.

METHODS AND RESULTS

We report on a family with recurrent fetal loss, where the parents had five affected fetuses/children with FADS and one healthy child. The fetuses displayed no fetal movements from the gestational age of 17 weeks, extended knee joints, flexed hips and elbows, and clenched hands. Whole exome sequencing of one affected fetus and the parents was performed. A novel homozygous frameshift mutation was identified in muscle, skeletal receptor tyrosine kinase (MuSK), c.40dupA, which segregated with FADS in the family. Haplotype analysis revealed a conserved haplotype block suggesting a founder mutation. MuSK (muscle-specific tyrosine kinase receptor), a component of the AChR pathway, is a main regulator of neuromuscular junction formation and maintenance. Missense mutations in MuSK have previously been reported to cause congenital myasthenic syndrome (CMS) associated with AChR deficiency.

CONCLUSIONS

To our knowledge, this is the first report showing that a mutation in MuSK is associated with FADS. The results support previous findings that CMS and/or FADS are caused by complete or severe functional disruption of components located in the AChR pathway. We propose that whereas milder mutations of MuSK will cause a CMS phenotype, a complete loss is lethal and will cause FADS.

Germline mutations in RYR1 are associated with foetal akinesia deformation sequence/lethal multiple pterygium syndrome

INTRODUCTION

Foetal akinesia deformation sequence syndrome (FADS) is a genetically heterogeneous disorder characterised by the combination of foetal akinesia and developmental defects which may include pterygia (joint webbing). Traditionally multiple pterygium syndrome (MPS) has been divided into two forms: prenatally lethal (LMPS) and non-lethal Escobar type (EVMPS) types. Interestingly, FADS, LMPS and EVMPS may be allelic e.g. each of these phenotypes may result from mutations in the foetal acetylcholine receptor gamma subunit gene (CHRNG). Many cases of FADS and MPS do not have a mutation in a known FADS/MPS gene and we undertook molecular genetic studies to identify novel causes of these phenotypes.

RESULTS

After mapping a novel locus for FADS/LMPS to chromosome 19, we identified a homozygous null mutation in the RYR1 gene in a consanguineous kindred with recurrent LMPS pregnancies. Resequencing of RYR1 in a cohort of 66 unrelated probands with FADS/LMPS/EVMPS (36 with FADS/LMPS and 30 with EVMPS) revealed two additional homozygous mutations (in frame deletions). The overall frequency of RYR1 mutations in probands with FADS/LMPS was 8.3%.

CONCLUSIONS

Our findings report, for the first time, a homozygous RYR1 null mutation and expand the range of RYR1-related phenotypes to include early lethal FADS/LMPS. We suggest that RYR1 mutation analysis should be performed in cases of severe FADS/LMPS even in the absence of specific histopathological indicators of RYR1-related disease.

First Trimester Ultrasound Diagnosis of Lethal Multiple Pterygium Syndrome

OBJECTIVE

Diagnosis of lethal multiple pterygium syndrome in the first trimester of pregnancy.

METHODS

A 38-year-old woman attended our ultrasound (US) clinic at 11.2 weeks gestation. She has had two previous stillbirths affected by lethal multiple pterygium syndrome. Transabdominal and transvaginal US were performed and identified a recurrence. Autopsy findings are compared to the fetal US findings.

RESULTS

Fetal US showed a markedly increased nuchal translucency, fixed flexion deformities of the elbows and knees bilaterally, cutaneous webs across both elbow joints and absent fetal movements. The patient decided to terminate the pregnancy and a D&C was performed. Pathology of intact fetal parts showed flexion deformity of the right elbow with a cutaneous web, and ulnar deviation of the right wrist.

CONCLUSION

Increased nuchal translucency, absent limb movements, multiple joint contractures and cutaneous webs on US allowed the diagnosis of lethal multiple pterygium syndromes in the first trimester of pregnancy.

Sonographic features of lethal multiple pterygium syndrome at 14 weeks

Lethal multiple pterygium syndrome is a rare inherited disorder. Previous reports suggest that the diagnosis may be based on prenatal sonographic demonstration of severe limb flexion, absence of fetal motion, and a large cystic hygroma in the second and third trimesters. We present the sonographic features and postmortem features of a fetus with lethal multiple pterygium syndrome at 13 weeks of gestation, which shows that the condition can possibly be diagnosed in the first trimester of pregnancy.

Prenatal diagnosis of multiple pterygium syndrome associated with Klinefelter syndrome

A nonlethal form of multiple pterygium syndrome (MPS) was diagnosed prenatally at 16 weeks of gestation with associated Klinefelter syndrome in the same fetus. The ultrasound findings were cystic hygroma, hypertelorism, micrognathia, low-set ears, flexion contractures of upper and lower extremities and rocker-bottom foot. Genetic amniocentesis revealed a 47,XXY karyotype. After genetic counseling, the parents decided to have a therapeutic abortion. We presented this case for the purpose of further describing the early ultrasound findings and clinical features of multiple pterygium syndromes. Also, what makes our patient unique is the coincidental presence of Klinefelter syndrome with MPS. To our knowledge, this is the first case in the literature in which a 47,XXY karyotype has been found in a fetus with multiple pterygium syndrome. The importance of delineating the exact subtype of MPS and making a precise differential diagnosis becomes critical during the process of evaluation of patients with MPS.

Recurrent fetal cystic hygroma with normal chromosomes: case report and review of the literature

Recurrence of fetal cystic hygroma in subsequent pregnancies is extremely rare. A review of the literature to date revealed only two other reports of recurrence with normal fetal karyotypes documented in at least two of the affected pregnancies. At 11 weeks' gestation, the fetus of a 19-year-old gravida 3 para 0 was discovered to have a large cystic hygroma. Subsequent evaluation during the second trimester revealed increasing size of the septated nuchal mass and ascites. A 46,XX fetal karyotype was noted in her two prior pregnancies, both of which had also been complicated by the development of cystic hygroma and nonimmune hydrops. Cystic hygroma, associated with a normal karyotype, can be inherited as an autosomal recessive trait.

Autosomal recessive multiple pterygium syndrome: a new variant?

Multiple pterygium syndromes include at least 15 different entities characterized by multiple pterygia or webs of the skin and multiple congenital anomalies. We describe a female infant who presented with a distinct constellation of multiple anomalies consisting of pterygia of the inguinal, intercrural and popliteal areas, flexion contractures and arthrogryposis of some joints, craniofacial anomalies including ectropion, medial canthal web, blepharophimosis, hypoplasia of nose, oral and nasopharyngeal cavities, vocal cords and tongue, micrognathia, orolabial synechiae secondary to pterygia, low set ears, alopecia, sad and expressionless face, short neck, asymmetric nipples, anal stenosis, rectal polyp, hypoplastic labia majora, complete syndactyly of all fingers and toes, pes equinovarus, bandlike web between feet, and absence of the nails and phalangeal-palmar creases. Radiological examination showed synostosis, absence or hypoplasia of metacarpal, metatarsal and phalangeal bones on feet and hands, and hypoplasia of pelvic bones and scapulae. This pattern of anomalies does not fit entirely any of the known multiple pterygium syndromes. Autosomal recessive inheritance is most likely due to the presence of three similarly affected siblings and normal parents.

Lethal multiple pterygium syndrome: suggestion for a consistent pathological workup and review of reported cases

We report on 2 brothers with lethal multiple pterygium syndrome (LMPS) born to non-consanguineous parents as late spontaneous abortions. Both fetuses presented with massive nuchal edema, and facial anomalies including cleft palate and broad ribs. Apparently, several subgroups of LMPS exist. Differentiation is difficult, as there is no consistent agreement on a workup protocol for autopsies. We compared the findings in the literature on cases with LMPS, and we suggest a standardized workup as an initial step for more efficient differentiation between various subgroups.

PHAVER syndrome: an autosomal recessive syndrome of limb pterygia, congenital heart anomalies, vertebral defects, ear anomalies, and radial defects

We have studied 2 sibs with vertebral, radial, congenital heart, and ear defects. The second patient also had limb pterygia and meningomyelocele. The abnormalities in these two sibs are seen in the VATER association; however, distinguishing these cases from the VATER association are the findings of pterygia, meningomyelocele, and probable autosomal recessive inheritance. We propose the acronym PHAVER syndrome for limb pterygia, heart defects, autosomal recessive inheritance, vertebral defects, ear anomalies and radial defects. This represents a new autosomal recessive disorder with phenotypic variability.

Lethal multiple pterygium syndrome: report of a case with neurological anomalies

We report on a 22-week female fetus with multiple pterygia, congenital joint contractures, muscle hypoplasia, cystic hygroma, hydrops, pulmonary and cardiac hypoplasia, facial anomalies, and growth retardation. Examination also documented microcephaly, brain immaturity, and severe cerebellar and pontine hypoplasia with absence of the pyramidal tracts. The spinal cord showed a marked decrease in size of all white matter tracts. The muscles were markedly hypoplastic. The relation of the neurological findings to the development of the syndrome is discussed.

Prognosis in fetal cystic hygroma

Axillary and lateral cervical fetal cystic hygromas in a fetus with normal karyotype are described. Fetal death at 25 weeks' gestation occurred. A literature review revealed that for cystic hygroma 42% of infants are 45XO, 38% have a normal karyotype, and 18% have trisomies. Prognosis is grim if the karyotype is abnormal or if hydrops or bilateral pleural effusions are present. Survival rate progressively improves with normal karyotype (27%), unilateral pleural effusion (40%), atypical location (56%), and resolution of cystic hygroma (71%). No single feature signifies 100% survival. The overall survival rate for fetal cystic hygroma is 10%. Prognosis remains guarded regardless of all other factors until the fetus reaches 26 weeks' gestation, after which time a 67% chance of ultimate survival can be expected. Only 42% of documented survivors were completely normal at follow-up.

The lethal multiple pterygium syndrome: prenatal ultrasonographic and postmortem findings; a case report

In this report we present the prenatal ultrasonic and postmortem data of a male fetus of 25 weeks' gestational age with a lethal multiple pterygium syndrome. The importance of precise etiologic diagnosis in a midtrimester fetus with generalized edema and nuchal hygroma is emphasized.

Case of lethal multiple pterygium syndrome with special reference to the origin of pterygia

A case of lethal multiple pterygium syndrome is presented. Besides the anomalies usually associated with this syndrome, cardiac hypertrophy and connective tissue abnormalities were observed. On the basis of these observations, we suggest that an abnormally fragile collagen constitution is the principal disorder in the lethal multiple pterygium syndrome, which is responsible for the pathogenesis of fetal immobility, pterygia, and many of the associated anomalies.

The prenatal sonographic diagnosis of lethal multiple pterygium syndrome: a heritable cause of recurrent abortion

Presumably, a large number of recurrent abortions are caused by lethal recessive syndromes whose diagnosis depends either on a known family history or on the identification of characteristic fetal phenotypic features on pathologic examination. Because these conditions are rare, family histories are seldom helpful, and nondirected postmortem examinations on degenerating samples are seldom enlightening. Serial ultrasonography beginning early in pregnancy may provide important information in the evaluation of recurrent abortion caused by lethal recessive disorders. Reported is the accurate prenatal sonographic diagnosis of lethal multiple pterygium syndrome in a patient with a history of recurrent abortions. This syndrome is characterized by multiple limb contractures with pterygia, facial clefting, intracranial abnormalities, cystic hygroma, progressive fetal edema, and fetal death by midgestation. Inheritance may be X-linked recessive. Lethal multiple pterygium syndrome should be considered in patients with a history of recurrent midtrimester losses.

Autosomal dominant antecubital pterygium: syndromic status substantiated

An autosomal dominant (AD) antecubital pterygium syndrome has been documented on the Indian Ocean Island of Rodrigues, and 11 affected family members in five generations have been studied over four decades. The consistent features include a fleshy web extending across the anterior aspect of the cubital fossa, absence of the long head of the triceps, limitation of full elbow extension and missing skin creases over the terminal inter-phalangeal joints of the fingers. On the basis of our observations, we consider that this condition warrants acceptance as an autonomous AD entity.