Identification of a novel CNTNAP1 mutation causing arthrogryposis multiplex congenita with cerebral and cerebellar atrophy

Arthrogryposis multiplex congenital, the occurrence of multiple joint contractures at birth, can in some cases be accompanied by insufficient myelination of peripheral nerves, muscular hypotonia, reduced tendon reflexes, and respiratory insufficiency. Recently mutations in the CASPR/CNTN1 complex have been associated with similar severe phenotypes and CNTNAP1 gene mutations, causing loss of the CASPR protein, were shown to cause severe, prenatal onset arthrogryposis multiplex congenita in four unrelated families. Here we report a consanguineous Arab family from Qatar with three children having an early lethal form of arthrogryposis multiplex congenita and a novel frameshift mutation in CNTNAP1. We further expand the existing CNTNAP1-associated phenotype to include profound cerebral and cerebellar atrophy.     

产前诊断先天性多发性关节挛缩症的探索

先天性多发性关节挛缩症(arthrogryposis multiplex congenita,AMC)是一种少见的先天性疾病,产前诊断先天性多发性关节挛缩症更是罕见,国内仅有极少数例报道。我们最近报道2例,除2个或以上关节屈曲,挛缩外,其中1例的一些体征,如小下颌,颈蹼,颈部皮肤增厚,积水(水肿),上下肢蹼状畸形等国内未见报道;结合国外学者产前诊断的相关文献报道,提出先天性多发性关节挛缩症的超声产前诊断和鉴别要点,超声产前诊断先天性多发性关节挛缩症进行有价值的探索。     

Unusual complications at birth in a stillborn with spinal muscular atrophy

A report is given on a premature stillborn with severe congenital spinal muscular atrophy, arthrogryposis multiplex congenita and hydrops fetalis. During delivery the head was spontaneously pulled off. The neuromuscular disease was the cause of this unusual complication. No alterations of collagenous fibres were found by light and electron microscopy in dermis, aorta or in the Achilles tendon. The hydrops fetalis was not of immunological nature.     

Report on the fifth international conference on neuronal ceroid-lipofuscinoses

Distal arthrogryposis IIB is characterized by contractures of the distal joints (especially of the fingers and toes) and ptosis. We recently encountered a father and son with these manifestations. The father was reported 54 years ago as a case of amyoplasia congenita (arthrogryposis multiplex congenita). Both father and son have distal joint contractures, most severe in the hands and feet, as well as ptosis and ophthalmoplegia. In addition, these patients have an unusual distribution of hair loss, and conical teeth. Whether these latter findings are related to the type of distal arthrogryposis present in this family is not known. In spite of their physical limitations both father and son have maintained an active life-style. © 1995 Wiley-Liss, Inc.     

Congenital muscular dystrophy associated with lethal arthrogryposis multiplex congenita

Summary Two unrelated patients with severe arthrogryposis multiplex congenita (AMC) who died perinatally, are presented. In both, postmortem examination revealed an intact nervous system and striking dystrophic muscle changes, consistent with congenital muscular dystrophy (CMD). Few similar cases have been reported before, but since the condition is not well known, it seems probable that in the past many have been labeled as mere multiple malformations. The possibility of an underlying muscular disorder, either primary myopathic or neurogenic should be considered in any patient with early lethal AMC. Our findings confirm that the fetal akinesia-arthrogryposis sequence is a nonspecific clinical syndrome resulting from various causes of muscular inactivity in utero. The main objective of this report is to provide reasonable guidelines on how to approach the problem of classification. We favor a pathogenetic approach, depending upon careful sampling of the central nervous system and skeletal muscles at autopsy.     

A dominantly inherited form of arthrogryposis multiplex congenita with unusual dermatoglyphics

A father and daughter with arthrogryposis multiplex congenita and similar dermatoglyphic patterns are described. No evidence was found of chromosomal abnormality, neuropathy or myopathy, and there were no other affected family members. The findings are compatible with autosomal dominant inheritance.     

Lethal arthrogryposis multiplex congenita

Twenty-one cases of arthrogryposis multiplex congenita, which had resulted in death soon after birth or had been aborted following prenatal diagnosis, were studied. Histochemical and histological study of muscle indicated that 11 cases were of myogenic origin, including congenital muscular dystrophy in 10 cases from six families and nemaline rod myopathy in one. Neurogenic causation was established in five cases, including three with intra-uterine anoxic-ischaemic damage and two siblings with a severe form of cerebro-ocular-facio-skeletal syndrome. Causation remained uncertain in five. Unusual features included atrophy or amyoplasia of the diaphragm associated with lung hypoplasia in 10 cases and evidence of birth trauma in seven cases. One pair of siblings had subcutaneous tissue of doughy consistency and another pair had bladder hypertrophy. Familial recurrence was seen most often in cases with evidence of myogenic origin. We consider that neuropathology and muscle histochemistry are essential aids in determining the risks of recurrence in this group of lethal conditions which defy analysis by syndrome recognition techniques.     

Amyoplasia congenita of the lower extremity: report in a premature baby

Amyoplasia congenita is a diagnostic subgroup of children with arthrogryposis multiplex congenita (AMC). AMC is a relatively rare syndrome characterized by multiple joint contractures at birth. Amyoplasia congenita is the most common type of this syndrome with an occurrence rate of 1 in 10,000 live births, and mainly refers to the disorders with limb involvement. In this report, the author presents a premature baby with amyoplasia congenita, whose hips showed flexion, abduction, and external rotation contractures. The knees showed fixed extension contractures, so that his lower extremities were cylindrical with absent skin creases at birth.     

Arthrogryposis Multiplex Congenita: Neurogenic Type with Autosomal Recessive Inheritance

An infant affected by severe arthrogryposis multiplex congenita leading to death in infancy due to neurogenic atrophy is described. Six other sibs were similarly affected. An autosomal recessive mode of inheritance is suggested.     

Arthrogryposis, ophthalmoplegia, and retinopathy: confirmation of a new type of arthrogryposis.

Arthrogryposis multiplex congenita is a heterogeneous condition and many different types are clinically recognisable. Recently, a new type of autosomal dominant arthrogryposis was described in a father and son. We report on a male patient with similar clinical features, confirming this distinct type of arthrogryposis. The condition is characterised by congenital contractures of the hands and feet with diminished or absent phalangeal creases, ophthalmoplegia, a rigid trunk, deep set eyes, and (in the oldest patient) an abnormal electroretinogram. Differential diagnosis from amyoplasia, the different types of distal arthrogryposis, and symphalangism is discussed.     

Arthrogryposis as neonatal presentation of Loeys-Dietz syndrome due to a novel TGFBR2 mutation

Loeys–Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder characterized mainly by cardiovascular, craniofacial and skeletal features. We report on a patient with LDS, whose prenatal examination was compatible with the diagnosis of arthrogryposis multiplex congenita. Neonatal assessment showed craniofacial and cardiovascular findings suggestive of LDS whose diagnosis was confirmed by the detection of a novel mutation (HGVN: NM_003242.5 (TGFBR2): c.1381T > C (p.(Cys461Arg))) in the TGFBR2 gene. Few prenatal and neonatal cases of LDS have been reported in the literature. We reviewed all cases reported to date with perinatal onset to delineate the clinical manifestations that allow us to prompt diagnosis of this syndrome at an early stage to prevent fatal cardiovascular complications. Furthermore we discuss the multidisciplinary follow up required in these patients.     

Gene ontology analysis of arthrogryposis (multiple congenital contractures)

In 2016, we published an article applying Gene Ontology Analysis to the genes that had been reported to be associated with arthrogryposis (multiple congenital contractures) (Hall & Kiefer, 2016). At that time, 320 genes had been reported to have mutations associated with arthrogryposis. All were associated with decreased fetal movement. These 320 genes were analyzed by biological process and cellular component categories, and yielded 22 distinct groupings. Since that time, another 82 additional genes have been reported, now totaling 402 genes, which when mutated, are associated with arthrogryposis (arthrogryposis multiplex congenita). So, we decided to update the analysis in order to stimulate further research and possible treatment. Now, 29 groupings can be identified, but only 19 groups have more than one gene.     

Arthrogryposis multiplex congenita: spectrum of pathologic changes

The pathologic features of muscle and/or spinal cord were studied in 96 infants and children with contractures of multiple joints (arthrogryposis multiplex congenita), usually in association with other congenital abnormalities. Ninety of these infants had a neurogenic form of arthrogryposis, and six had primary muscle disease. The neurogenic form, unlike the myopathic form, was usually associated with other congenital abnormalities. The most frequently associated congenital changes were low-set ears, micrognathia, wide flat nose, short neck, congenital heart disease, high-arched palate, hypoplastic lungs, and cryptorchidism. Some of the associated abnormalities could be attributed to muscle weakness, occurring during intrauterine development. A variety of skeletal muscle changes were observed, including primary myopathic alterations, fiber type predominance and disproportion, hypoplasia, aplasia, and denervation atrophy. When the primary alterations were in the spinal cord, abnormalities of anterior horn cells of several distinct types were recognized--absence of cells, diminution, dysgenesis, degeneration, and axonal reaction. The changes in anterior roots corresponded to those of the anterior horn cells.     

Asymptomatic maternal myasthenia as a cause of the Pena-Shokeir phenotype

We report six sibs with arthrogryposis multiplex congenita and a Pena-Shokeir phenotype, born to a healthy woman who was discovered to have asymptomatic myasthenia gravis (MG). This is the first report of anti-acetylcholine receptor (AChR) antibodies causing fetal akinesia/hypokinesia sequence in the offspring of an asymptomatic mother.     

Collaborating to advance interdisciplinary care for individuals with arthrogryposis

This Special Issue on Interdisciplinary Care in Arthrogryposis highlights a collection of articles spanning topics in interdisciplinary care, genetic discoveries, and clinical research. An international group of clinicians and researchers from various backgrounds who attended the “3rd International Symposium on Arthrogryposis”, held in Philadelphia, September 24–26, 2018, were invited to contribute to this issue. The goal of the 2018 Symposium and of this Special Issue is to provide momentum to advancing evidence‐based practice and research in arthrogryposis, by working collaboratively with adults and families of children with arthrogryposis, clinicians, and researchers. The contents of this issue cover a range of topics from defining and classifying arthrogryposis multiplex congenita to early detection, rehabilitation, and orthopedic management, advances in genetic pathways, patient registries, autopsy guidelines, and research findings in the pediatric and adult populations with arthrogryposis. We hope that this issue provides an overview as well as new knowledge on arthrogryposis to generate more conversations at the international level, and advance care and research for individuals with arthrogryposis.     

Antibodies to acetylcholine receptor in parous women with myasthenia: evidence for immunization by fetal antigen

The weakness in myasthenia gravis (MG) is mediated by autoantibodies against adult muscle acetylcholine receptors (AChR) at the neuromuscular junction; most of these antibodies also bind to fetal AChR, which is present in the thymus. In rare cases, babies of mothers with MG, or even of asymptomatic mothers, develop a severe developmental condition, arthrogryposis multiplex congenita, caused by antibodies that inhibit the ion channel function of the fetal AChR while not affecting the adult AChR. Here we show that these fetal AChR inhibitory antibodies are significantly more common in females sampled after pregnancy than in those who present before pregnancy, suggesting that they may be induced by the fetus. Moreover, we were able to clone high-affinity combinatorial Fab antibodies from thymic cells of two mothers with MG who had babies with arthrogryposis multiplex congenita. These Fabs were highly specific for fetal AChR and did not bind the main immunogenic region that is common to fetal and adult AChR. The Fabs show strong biases to VH3 heavy chains and to a single Vkappa1 light chain in one mother. Nevertheless, they each show extensive intraclonal diversification from a highly mutated consensus sequence, consistent with antigen-driven selection in successive steps. Collectively, our results suggest that, in some cases of MG, initial immunization against fetal AChR is followed by diversification and expansion of B cells in the thymus; maternal autoimmunity will result if the immune response spreads to the main immunogenic region and other epitopes common to fetal and adult AChR.     

Arthrogryposis multiplex congenita,craniofacial, and ophthalmological abnormalities and normal intelligence: A new syndrome?

We report on an 8-year-old boy with clinical manifestations suggestive of a new arthrogryposis syndrome. These included characteristic craniofacial abnormalities, cleft palate, arthrogryposis multiplex congenita, pulmonary hypoplasia, cryptorchidism, and unusual ophthalmological findings. There was no intrauterine growth retardation or decreased fetal movements. Despite the poor prognosis expected in early life, the patient presented with normal mental capability on follow-up. Family data showed that a maternal first cousin of the mother (mother's brother's son) had similar findings and died in infancy. Differential diagnosis included Pena-Shokeir syndrome or phenotype, Gordon syndrome, Marden-Walker syndrome, and the syndrome of arthrogryposis with ophthalmoplegia and retinopathy. The possibility of autosomal dominant inheritance with reduced penetrance is suggested for this apparently new syndrome. Am. J. Med. Genet. 71:401–405, 1997. © 1997 Wiley-Liss, Inc.     

Asymptomatic maternal myasthenia as a cause of the Pena‐Shokeir phenotype

We report six sibs with arthrogryposis multiplex congenita and a Pena‐Shokeir phenotype, born to a healthy woman who was discovered to have asymptomatic myasthenia gravis (MG). This is the first report of anti‐acetylcholine receptor (AChR) antibodies causing fetal akinesia/hypokinesia sequence in the offspring of an asymptomatic mother. Am. J. Med. Genet. 92:1–6, 2000. © 2000 Wiley‐Liss, Inc.     

Congenital myopathy with fiber type disproportion: a family with a chromosomal translocation t(10; 17) may indicate candidate gene regions

A patient with myopathy and congenital fiber type disproportion presented at birth with arthrogryposis multiplex congenita, dislocation of the hips and mild scoliosis. Later in life she developed marked muscle weakness. A balanced chromosomal translocation t(10;17) (p11.2;q25), transmitted by the clinically healthy mother, who nevertheless showed discrete signs of myopathy, was demonstrated. DNA analysis excluded maternal uniparental disomy for loci on both chromosomes 10 and 17. We suggest that the translocation breakpoints are candidate regions for a myopathy gene.