An unusual bandlike web in an infant with lethal multiple pterygium syndrome

We report on a patient with a lethal multiple pterygium syndrome who also had an unusual, bandlike web across one axilla and partial intestinal atresia. Umbilical cord wrapping with subsequent vascular compromise appears to be the most likely pathogenetic mechanism for the additional anomalies.     

CHRNG‐related nonlethal multiple pterygium syndrome: Muscle imaging pattern and clinical,histopathological, and molecular genetic findings

Mutations in the CHRNG gene cause autosomal recessive multiple pterygium syndrome (MPS). Herein we present a long‐term follow‐up of seven patients with CHRNG‐related nonlethal MPS and we compare them with the 57 previously published patients. The objective is defining not only the clinical, histopathological, and molecular genetic characteristics, but also the type and degree of muscle involvement on whole‐body magnetic resonance imaging (WBMRI). CHRNG mutations lead to a distinctive phenotype characterized by multiple congenital contractures, pterygium, and facial dysmorphism, with a stable clinical course over the years. Postnatal abnormalities at the neuromuscular junction were observed in the muscle biopsy of these patients. WBMRI showed distinctive features different from other arthrogryposis multiple congenita. A marked muscle bulk reduction is the predominant finding, mostly affecting the spinal erector muscles and gluteus maximus. Fatty infiltration was only observed in deep paravertebral muscles and distal lower limbs. Mutations in CHRNG are mainly located at the extracellular domain of the protein. Our study contributes to further define the phenotypic spectrum of CHRNG‐related nonlethal MPS, including muscle imaging features, which may be useful in distinguishing it from other diffuse arthrogryposis entities.     

Lethal multiple pterygium syndrome in an 18-week fetus with hydrops

We present the case of an 18-week abortus with lethal multiple pterygium syndrome and hydrops. Radiographic and anatomic study showed none of the bony abnormalities reported in live-born children with multiple pterygium syndrome. The pathogenesis of the hydrops was not apparent. The findings of cleft palate, pulmonary hypoplasia, muscular atrophy, gracile thoracic bones, and fetal death are typical of the lethal variant.     

Limb pterygium syndromes: A review and report of eleven patients

Conditions with limb pterygia and congenital contractures were reviewed as part of a study of over 350 infants with arthrogryposis. Emphasis was placed on inheritance and variability of distinct pterygium conditions. Eleven patients with limb pterygia were recognized in our study and are described here. Seven of the 350 patients with congenital contractures had the autosomal recessively inherited multiple pterygium syndrome (Patients 1–7). Three of the seven are sibs, a fourth was born to consanguineous parents, and three were chance isolated cases. These seven had multiple joint webs, unusual finger contractures, syndactyly, rocker bottom feet, ptosis, antimongoloid slant of palpebral fissures, epicanthal folds, highly arched palate, scoliosis, and short stature. There is intrafamilial variability. Three patients from one family had a lethal multiple pterygium syndrome. Two were monozygotic twins. They had webbing and contractures of the elbows, knees, neck, and fingers, calcaneovalgus deformity of the feet, and an unusual facial appearance: hypertelorism, flat nose, antimongoloid slant of palpebral fissures, apparently low-set ears. One had a cleft palate. Internal malformations included: bilateral pulmonary hypoplasia, small heart, absence of the appendix, and attenuation of the ascending and transverse colon. One sporadic case of lethal popliteal pterygium with facial clefts was studied. Multiple anomalies included: ankyloblepharon filiforme adnatum, upslanting palpebral fissures, hypoplasia of nasal cartilages, frenula, clefts into the oropharynx lateral to the mouth, apparently low-set ears with slit-like canals, large popliteal pterygia, syndactyly with fusion of all digits in hands and feet, and hypoplastic labia.     

Multiple pterygium syndrome with body asymmetry

We report on a fetus with multiple pterygia in the popliteal, antecubital, intercrural, axillary, and nuchal region, arthrogryposis, camptodactyly, anal atresia, hypospadias, ambiguous genitalia, and neonatal death. Arthrogryposis was much more pronounced at the left than at the right side. Moreover, there was gross body asymmetry with hypoplasia of the left arm, leg, pelvis, and kidney. As this spectrum of anomalies does not fit any of the known multiple pterygium syndromes, this patient adds another clinical entity to the already wide spectrum of multiple pterygium syndromes. © 1993 Wiley-Liss, Inc.     

Bartsocas-Papas syndrome in an Arab family with four affected sibs: Further characterization

Bartsocas-Papas syndrome is a severe autosomal recessive popliteal pterygium syndrome. Other anomalies include microcephaly, facial clefts, filiform bands, ankyloblepharon, syndactyly, and other ectodermal and nonectodermal anomalies. We report on four Arab sibs with manifestations of this syndrome and some additional traits that include cutis aplasia, widely spaced nipples, low-set umbilicus, and unilateral renal hypoplasia among others. One was stillborn, and the other three children lived 10−17 months. Parents were nonconsanguineous, derived from different Bedouin tribes in Qatar and the United Arab Emirates. Similar cases from the literature are reviewed. Am. J. Med. Genet. 79:16–21, 1998. © 1998 Wiley-Liss, Inc.     

Homozygous/compound heterozygote RYR1 gene variants: Expanding the clinical spectrum

The ryanodine receptor 1 (RYR1) is a calcium release channel essential for excitation‐contraction coupling in the sarcoplasmic reticulum of skeletal muscles. Dominant variants in the RYR1 have been well associated with the known pharmacogenetic ryanodinopathy and malignant hyperthermia. With the era of next‐generation gene sequencing and growing number of causative variants, the spectrum of ryanodinopathies has been evolving with dominant and recessive variants presenting with RYR1‐related congenital myopathies such as central core disease, minicore myopathy with external ophthalmoplegia, core‐rod myopathy, and congenital neuromuscular disease. Lately, the spectrum was broadened to include fetal manifestations, causing a rare recessive and lethal form of fetal akinesia deformation sequence syndrome (FADS)/arthrogryposis multiplex congenita (AMC) and lethal multiple pterygium syndrome. Here we broaden the spectrum of clinical manifestations associated with homozygous/compound heterozygous RYR1 gene variants to include a wide range of manifestations from FADS through neonatal hypotonia to a 35‐year‐old male with AMC and PhD degree. We report five unrelated families in which three presented with FADS. One of these families was consanguineous and had three affected fetuses with FADS, one patient with neonatal hypotonia who is alive, and one individual with AMC who is 35 years old with normal intellectual development and uses a wheelchair. Muscle biopsies on these cases demonstrated a variety of histopathological abnormalities, which did not assist with the diagnostic process. Neither the affected living individuals nor the parents who are obligate heterozygotes had history of malignant hyperthermia.     

The acrocallosal syndrome in sisters

Two sisters born to non-consanguineous healthy parents are described who present the following abnormalities: macrocephalus, prominent forehead, hypertelorism, absence of the corpus callosum, inguinal hernias, duplication of hallucal phalanges and severe mental retardation. The older sister in addition had cleft palate, while only the younger had a supratentorial cyst between cerebrum and cerebellum and epileptic fits. After 6 sporadic cases, this is the first instance of siblings with the acrocallosal syndrome. This observation and definite and possible parental consanguinity in two further patients suggest that this syndrome might be recessively inherited.     

Fetal akinesia deformation sequence syndrome associated with recessive TTN variants

Arthrogryposis multiplex congenita (AMC) [also known as multiple joints contracture or Fetal Akinesia Deformation Sequence (FADS)] is etiologically a heterogeneous condition with an estimated incidence of approximately 1 in 3000 live births and much higher incidence when prenatally diagnosed cases are included. The condition can be acquired or secondary to fetal exposures and can also be caused by a variety of single-gene disorders affecting the brain, spinal cord, peripheral nerves, neuromuscular junction, muscle, and a variety of disorders affecting the connective tissues (Niles et al., Prenatal Diagnosis, 2019; 39:720–731). The introduction of next-generation gene sequencing uncovered many genes and causative variants of AMC but also identified genes that cause both dominant and recessive inherited conditions with the variability of clinical manifestations depending on the genes and variants. Molecular diagnosis in these cases is not only important for prognostication but also for the determination of recurrence risk and for providing reproductive options including preimplantation and prenatal diagnosis. TTN, the largest known gene in the human genome, has been known to be associated with autosomal dominant dilated cardiomyopathy. However, homozygote and compound heterozygote pathogenic variants with recessive inheritance have rarely been reported. We report the effect of recessive variants located within the fetal IC and/or N2BA isoforms in association with severe FADS in three families. All parents were healthy obligate carriers and none of them had cardiac or skeletal muscle abnormalities. This report solidifies FADS as an alternative phenotypic presentation associated with homozygote/compound heterozygous pathogenic variants in the TTN.     

Two sisters with Toriello-Carey syndrome

Toriello-Carey syndrome comprises agenesis of the corpus callosum, telecanthus, short palpebral fissures, small nose with anteverted nares, Robin sequence, abnormally shaped ears, cardiac defect, and hypotonia. We describe two Japanese sisters with a Toriello-Carey syndrome whose phenotypes were as severe as reported male cases. The younger sister died suddenly at age 4 months. Our patients with a severe phenotype and possible parental consanguinity suggest autosomal recessive inheritance of Toriello-Carey syndrome.     

Fetal arthrogryposis: Challenges and perspectives for prenatal detection and management

Antenatal identification of fetuses with multiple congenital contractures or arthrogryposis multiplex congenita (AMC) may be challenging. The first clinical sign is often reduced fetal movement and/or contractures, as seen on prenatal ultrasounds. This can be apparent at any point, from early to late pregnancy, may range from mild to severe involvement, with or without associated other structural anomalies. Possible etiologies and their prognosis need to be interpreted with respect to developmental timing. The etiology of AMC is highly heterogeneous and making the specific diagnosis will guide prognosis, counseling and prenatal and perinatal management. Current ultrasound practice identifies only approximately 25% of individuals with arthrogryposis prenatally before 24 weeks of pregnancy in a general obstetrics care population. There are currently no studies and guidelines that address the question of when and how to assess for fetal contractures and movements during pregnancy. The failure to identify fetuses with arthrogryposis before 24 weeks of pregnancy means that physicians and families are denied reproductive options and interventions that may improve outcome. We review current practice and recommend adjusting the current prenatal imaging and genetic diagnostic strategies to achieve early prenatal detection and etiologic diagnosis. We suggest exploring options for in utero therapy to increase fetal movement for ongoing pregnancies.     

New syndrome of spondylospinal thoracic dysostosis with multiple pterygia and arthrogryposis

We describe a “new” syndrome of spondylospinal thoracic dysostosis with a short curved spine and fusion of the spinous processes, short thorax with “crab-like” configuration of the ribs, pulmonary hypoplasia, severe arthrogryposis and multiple pterygia, and hypoplastic maxilla and mandible in two siblings. This appears to be an autosomal recessive lethal trait. A literature review revealed two reports of four similar or related cases. Am. J. Med. Genet. 69:73–78, 1997. © 1997 Wiley-Liss, Inc.     

Two sisters resembling Gorlin-Chaudhry-Moss syndrome

The Gorlin-Chaudhry-Moss syndrome (GCMS), was describe initially by Gorlin et al. [Gorlin et al. (1960)] in two sisters with craniosynostosis, hypertrichosis, hypoplastic labia majora, dental defects, eye anomalies, patent ductus arteriosus, and normal intelligence. Two other sporadic instances have been documented. Here, we report on two sisters with a condition with some similarities to GCMS as well as some differences, which could represent either previously unreported variability in GCMS, or it may represent a novel disorder.     

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.     

Survival among children with “Lethal” congenital contracture syndrome 11 caused by novel mutations in the gliomedin gene (GLDN)

Biallelic GLDN mutations have recently been identified among infants with lethal congenital contracture syndrome 11 (LCCS11). GLDN encodes gliomedin, a protein required for the formation of the nodes of Ranvier and development of the human peripheral nervous system. We report six infants and children from four unrelated families with biallelic GLDN mutations, four of whom survived beyond the neonatal period into infancy, childhood, and late adolescence with intensive care and chronic respiratory and nutritional support. Our findings expand the genotypic and phenotypic spectrum of LCCS11 and demonstrate that the condition may not necessarily be lethal in the neonatal period.     

Research platform for children with arthrogryposis multiplex congenita: Findings from the pilot registry

A pediatric registry for arthrogryposis multiplex congenita (AMC) proposes to advance research by providing the platform to inform the distribution, etiology, and natural history of AMC. The registry was piloted on 40 families of children (mean = 8.25 years, 48% males) presenting with AMC across two hospitals in North America. Data on the child's demographic and newborn variables, mothers' and fathers' demographic variables, lifestyle habits, and medical history were collected using a telephone interview with the primary caregiver and review of medical charts. Mean gestational age was 38 weeks, 97% of children presented with lower extremity deformities, and 74% of neonatal interventions targeted the lower extremity. Newborns spent an average of 14 days in the hospital (range 2–56 days) mostly for diagnostic workup and feeding difficulties. Half (49%) of the sample had internal organ involvement. Genetic testing was done on 48% of the children, including chromosome studies, single gene, whole‐exome/genome sequencing, and/or microarray studies. Genetic findings were inconclusive in most. Two‐thirds of mothers (67%) reported inconsistently feeling fetal movements. This pilot study contributed to the refinement of participant selection, identification of data source, expansion of data sets, and areas for future exploration prior to the implementation of a multisite AMC pediatric registry.     

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. Am. J. Med. Genet. 68:82–85, 1997 © 1997 Wiley-Liss, Inc.     

Three patients with Schaaf–Yang syndrome exhibiting arthrogryposis and endocrinological abnormalities

MAGEL2 is the paternally expressed gene within Prader–Willi syndrome critical region at 15q11.2. We encountered three individuals in whom truncating mutations of MAGEL2 were identified. Patients 1 and 2, siblings born to healthy, non‐consanguineous Japanese parents, showed generalized hypotonia, lethargy, severe respiratory difficulty, poor feeding, and multiple anomalies including arthrogryposis soon after birth. We carried out whole‐exome sequencing, which detected a MAGEL2 mutation (c.1912C>T, p.Gln638*, heterozygous). The patients’ father was heterozygous for the mutation. Patient 3 was a female infant, showed respiratory difficulty reflecting pulmonary hypoplasia, generalized hypotonia, feeding difficulty and multiple anomalies soon after birth. Targeted next‐generation sequencing detected a novel heterozygous mutation in MAGEL2 (c.3131C>A, p.Ser1044*). This mutation was not found in the parents. MAGEL2 mutations, first reported to be the cause of the Prader–Willi like syndrome with autism by Schaaf et al. (2013) Nature Genetics, 45: 1405–1408 show the wide range of phenotypic spectrum from lethal arthrogryposis multiplex congenital to autism spectrum disorder (ASD) and mild intellectual disability (ID). Our results indicate that MAGEL2 mutations cause multiple congenital anomalies and intellectual disability accompanied by arthrogryposis multiplex congenita and various endocrinologic abnormalities, supporting that the view that clinical phenotypes of MAGEL2 mutations are variable.

     

Multiple pterygium syndrome: a case complicated by malignant hyperthermia

The autosomal recessive multiple pterygium syndromes are a heterogeneous group of disorders in which multiple joint contractures are associated with cutaneous webbing. Recently, we evaluated a 33 week gestation male in whom multiple pterygia were one feature of a broader pattern of malformation. Clinical management was adversely affected by malignant hyperthermia. In this report we present the clinical, radiographic and pathologic data of this patient and those of an affected stillborn female sibling. We believe that these represent the features of a newly recognized disorder.