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Journal: American journal of medical genetics. Part C, Seminars in medical genetics

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49, XXXXY is a rare aneuploidy and variant of Klinefelter syndrome, occurring in 1 per 80,000-100,000 live births. We present a cohort of 40 affected males, focusing on musculoskeletal problems. Subjects were participants in an annual 49er family support group meeting. Children were examined in a multidisciplinary clinic by a pediatric neurologist and geneticist, a pediatric orthopedist, a neurodevelopmentalist, and two physical therapists. The patient data were collected from this clinic from 2004 to 2012. All patients were required to have karyotypes that confirmed the presence of XXXXY. There was a high prevalence of musculoskeletal disorders, particularly hypotonia (34 patients [85%]), radioulnar synostosis (30 [75%]), pes planus (26 [65%]), asymmetric hip rotation (27 [67.5%]), and clinodactyly (24 [60%]). Other, less common lower-extremity disorders, included, 5 patients (12.5%) with unilateral club foot, 5 boys (12.5%) with pes cavus, 10 patients (25%) genu valgum and 2 children with genu varus (5%). To our knowledge, this is the first large cohort of boys with 49, XXXXY that focuses on musculoskeletal disorders. There was an increased incidence of hypotonia, clubfoot, avascular necrosis of the femoral head, radioulnar synostosis, and pes planus compared to the normative population. Boys with 49, XXXXY would benefit from multidisciplinary evaluations, particularly from pediatric orthopedists, physical therapists, neurologists, and geneticists for appropriate medical care. © 2013 Wiley Periodicals, Inc.

Concepts: Varus deformity, Neurology, Avascular necrosis, Klinefelter's syndrome, Aneuploidy, Genu valgum, Genu varum, Congenital disorders of musculoskeletal system

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47,XXY (Klinefelter syndrome) is the most frequent sex chromosomal disorder and affects approximately one in 660 newborn boys. The syndrome is characterized by varying degrees of cognitive, social, behavioral, and learning difficulties and in adulthood additionally primary testicular failure with small testes, hypergonadotropic hypogonadism, tall stature, and eunuchoid body proportions. The phenotype is variable ranging from “near-normal” to a significantly affected individual. In addition, newborns with Klinefelter syndrome generally present with a normal male phenotype and the only consistent clinical finding in KS is small testes, that are most often not identified until after puberty. Decreased awareness of this syndrome among health professionals and a general perception that all patients with 47,XXY exhibit the classic textbook phenotype results in a highly under-diagnosed condition with up to 75% of the patients left undetected. Typically, diagnosis is delayed with the majority of patients identified during fertility workup in adulthood, and only 10% of patients diagnosed prior to puberty. Early detection of this syndrome is recommended in order to offer treatment and intervention at the appropriate ages and stages of development for the purpose of preventing osteopenia/osteoporosis, metabolic syndrome, and other medical conditions related to hypogonadism and to the XXY as well as minimizing potential learning and psychosocial problems. The aim of this review is to present the clinical aspects of XXY and the age-specific recommendations for medical management. © 2013 Wiley Periodicals, Inc.

Concepts: Psychology, Syndromes, Testicle, Klinefelter's syndrome, Aneuploidy, Y chromosome, Puberty, X chromosome

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X and Y chromosomal variations including tetrasomy and pentasomy conditions are rare and occur in 1:18,000-1:100,000 male births. The most common sex chromosome aneuploidy is 47, XXY for which there is a rich literature delineating the physical and neurobehavioral phenotype. Although the more complex chromosome aneuploidies 48, XXYY, 48, XXXY, and 49, XXXXY are often compared with 47, XXY (Klinefelter syndrome) because of shared features including tall stature and hypergonadotropic hypogonadism, there is a wider spectrum of physical and cognitive abilities that have recently been delineated. The phenotypic presentation of the boys with more severe aneuploidy shares some characteristics with 47, XXY, but there are also other unique and distinctive features. Previously unappreciated intact nonverbal skills have been demonstrated in association with severe developmental dyspraxia. MRI findings of white matter hyperintensities may underlie cognitive deficits and deserve further study. This report discusses what is known about clinical variability in the XY syndromes collectively evaluated through careful multidisciplinary clinical evaluation including the clinical and neurobehavioral aspects of these conditions. Variability in clinical and cognitive functioning may reflect skewed X inactivation, mosaicism, or epigenetic factors that warrant further investigation. © 2013 Wiley Periodicals, Inc.

Concepts: Chromosome, Klinefelter's syndrome, Aneuploidy, Y chromosome, X chromosome, X-inactivation, Mosaic, Tetrasomy

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Nicolaides-Baraitser syndrome (NCBRS) is an intellectual disability (ID)/multiple congenital anomalies syndrome caused by non-truncating mutations in the ATPase region of SMARCA2, which codes for one of the two alternative catalytic subunits of the BAF chromatin remodeling complex. We analyzed 61 molecularly confirmed cases, including all previously reported patients (n = 47) and 14 additional unpublished individuals. NCBRS is clinically and genetically homogeneous. The cardinal features (ID, short stature, microcephaly, typical face, sparse hair, brachydactyly, prominent interphalangeal joints, behavioral problems and seizures), are almost universally present. There is variability however, as ID can range from severe to mild, and sparse hair may be present only in certain age groups. There may be a correlation between the severity of the ID and presence of seizures, absent speech, short stature and microcephaly. SMARCA2 mutations causing NCBRS are likely to act through a dominant-negative effect. There may be some genotype-phenotype correlations (mutations at domain VI with severe ID and seizures; mutations affecting residues Pro883, Leu946, and Ala1201 with mild phenotypes) but numbers are still too small to draw definitive conclusions. © 2014 Wiley Periodicals, Inc.

Concepts: DNA, Gene, Genetics, Genotype, Evolution, Phenotype, Human height, Genotype-phenotype distinction

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In the last decade, increasing attention has been devoted to the extra-articular and extra-cutaneous manifestations of joint hypermobility syndrome, also termed Ehlers-Danlos syndrome, hypermobility type (i.e., JHS/EDS-HT). Despite the fact that the current diagnostic criteria for both disorders remain focused on joint hypermobility, musculoskeletal pain and skin changes, medical practice and research have started investigating a wide spectrum of visceral, neurological and developmental complications, which represent major burdens for affected individuals. In particular, children with generalized joint hypermobility often present with various neurodevelopmental issues and can be referred for neurological consultation. It is common that investigations in these patients yield negative or inconsistent results, eventually leading to the exclusion of any structural neurological or muscle disorder. In the context of specialized clinics for connective tissue disorders, a clear relationship between generalized joint hypermobility and a characteristic neurodevelopmental profile affecting coordination is emerging. The clinical features of these patients tend to overlap with those of developmental coordination disorder and can be associated with learning and other disabilities. Physical and psychological consequences of these additional difficulties add to the chief manifestations of the pre-existing connective tissue disorder, affecting the well-being and development of children and their families. In this review, particular attention is devoted to the nature of the link between joint hypermobility, coordination difficulties and neurodevelopmental issues in children. Presumed pathogenesis and management issues are explored in order to attract more attention on this association and nurture future clinical research. © 2015 Wiley Periodicals, Inc.

Concepts: Medicine, Collagen, Syndromes, Marfan syndrome, Connective tissue, Ehlers-Danlos syndrome, Hypermobility, Contortion

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Arthrogryposis multiplex congenita (AMC) has been described and defined in thousands of articles, but the terminology used has been inconsistent in clinical and research communities. A definition of AMC was recently developed using a modified Delphi consensus method involving 25 experts in the field of AMC from 8 countries. Participants included health care professionals, researchers, and individuals with AMC. An annotation of the definition provides more in-depth explanations of the different sentences of the AMC definition and is useful to complement the proposed definition. The aim of this study was to provide an annotation of the proposed consensus-based AMC definition. For the annotation process, 17 experts in AMC representing 10 disciplines across 7 countries participated. A paragraph was developed for each sentence of the definition using an iterative process involving multiple authors with varied and complementary expertise, ensuring all points of view were taken into consideration. The annotated definition provides an overview of the different topics related to AMC and is intended for all stakeholders, including youth and adults with AMC, their families, and clinicians and researchers, with the hopes of unifying the understanding of AMC in the international community.

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The Ehlers-Danlos syndromes (EDS) are a heterogeneous group of heritable connective tissue disorders characterized by joint hypermobility, skin extensibility, and tissue fragility. This communication briefly reports upon the neurological manifestations that arise including the weakness of the ligaments of the craniocervical junction and spine, early disc degeneration, and the weakness of the epineurium and perineurium surrounding peripheral nerves. Entrapment, deformation, and biophysical deformative stresses exerted upon the nervous system may alter gene expression, neuronal function and phenotypic expression. This report also discusses increased prevalence of migraine, idiopathic intracranial hypertension, Tarlov cysts, tethered cord syndrome, and dystonia, where associations with EDS have been anecdotally reported, but where epidemiological evidence is not yet available. Chiari Malformation Type I (CMI) has been reported to be a comorbid condition to EDS, and may be complicated by craniocervical instability or basilar invagination. Motor delay, headache, and quadriparesis have been attributed to ligamentous laxity and instability at the atlanto-occipital and atlantoaxial joints, which may complicate all forms of EDS. Discopathy and early degenerative spondylotic disease manifest by spinal segmental instability and kyphosis, rendering EDS patients prone to mechanical pain, and myelopathy. Musculoskeletal pain starts early, is chronic and debilitating, and the neuromuscular disease of EDS manifests symptomatically with weakness, myalgia, easy fatigability, limited walking, reduction of vibration sense, and mild impairment of mobility and daily activities. Consensus criteria and clinical practice guidelines, based upon stronger epidemiological and pathophysiological evidence, are needed to refine diagnosis and treatment of the various neurological and spinal manifestations of EDS. © 2017 Wiley Periodicals, Inc.

Concepts: Central nervous system, Nervous system, Intracranial pressure, Muscle, Neurology, Ehlers-Danlos syndrome, Arnold-Chiari malformation, Tethered spinal cord syndrome

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Chronic fatigue is an important contributor to impaired health-related quality of life in Ehlers-Danlos syndrome. There is overlap in the symptoms and findings of EDS and chronic fatigue syndrome. A proportion of those with CFS likely have EDS that has not been identified. The evaluation of chronic fatigue in EDS needs to include a careful clinical examination and laboratory testing to exclude common causes of fatigue including anemia, hypothyroidisim, and chronic infection, as well as dysfunction of major physiological or organ systems. Other problems that commonly contribute to fatigue in EDS include sleep disorders, chronic pain, deconditioning, cardiovascular autonomic dysfunction, bowel and bladder dysfunction, psychological issues, and nutritional deficiencies. While there is no specific pharmacological treatment for fatigue, many medications are effective for specific symptoms (such as headache, menstrual dysfunction, or myalgia) and for co-morbid conditions that result in fatigue, including orthostatic intolerance and insomnia. Comprehensive treatment of fatigue needs to also evaluate for biomechanical problems that are common in EDS, and usually involves skilled physical therapy and attention to methods to prevent deconditioning. In addition to managing specific symptoms, treatment of fatigue in EDS also needs to focus on maintaining function and providing social, physical, and nutritional support, as well as providing on-going medical evaluation of new problems and review of new evidence about proposed treatments. © 2017 Wiley Periodicals, Inc.

Concepts: Psychology, Medicine, Syndromes, Fatigue, Chronic fatigue syndrome, Postural orthostatic tachycardia syndrome, Ehlers-Danlos syndrome, Malaise

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Well known for their role in allergic disorders, mast cells (MCs) play a key role in homeostatic mechanisms and surveillance, recognizing and responding to different pathogens, and tissue injury, with an array of chemical mediators. After being recruited to connective tissues, resident MCs progenitors undergo further differentiation, under the influence of signals from surrounding microenvironment. It is the differential tissue homing and local maturation factors which result in a diverse population of resident MC phenotypes. An abundance of MC reside in connective tissue that borders with the external world (the skin as well as gastrointestinal, respiratory, and urogenital tracts). Situated near nerve fibers, lymphatics, and blood vessels, as well as coupled with their ability to secrete potent mediators, MCs can modulate the function of local and distant structures (e.g., other immune cell populations, fibroblasts, angiogenesis), and MC dysregulation has been implicated in immediate and delayed hypersensitivity syndromes, neuropathies, and connective tissue disorders (CTDs). This report reviews basic biology of mast cells and mast cell activation as well as recent research efforts, which implicate a role of MC dysregulation beyond atopic disorders and in a cluster of Ehlers-Danlos Syndromes, non-IGE mediated hypersensitivity disorders, and dysautonomia. © 2017 Wiley Periodicals, Inc.

Concepts: Immune system, Blood, Collagen, Allergy, Mast cell, Marfan syndrome, Connective tissue, Ehlers-Danlos syndrome

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Current evidence suggests that an association exists between non-inflammatory hereditary disorders of connective tissue such as the Ehlers-Danlos syndromes (EDS) and gastrointestinal (GI) symptoms. Patients with EDS can present with both structural problems such as hiatus hernias, visceroptosis, rectoceles, and rectal prolapse as well as functional problems such as disordered gut motility. It has recently been demonstrated that patients with hypermobile EDS (hEDS) present with GI symptoms related to the fore and hind-gut and these patients frequently meet the criteria for functional gastrointestinal disorders such as functional dyspepsia and irritable bowel syndrome. Presence of GI symptoms in EDS patients influences their quality of life. Specific evidence based management guidelines for the management of GI symptoms in EDS patients do not exist and these patients are often treated symptomatically. There is, however, recognition that certain precautions need to be taken for those patients undergoing surgical treatment. Future studies are required to identify the mechanisms that lead to GI symptoms in patients with EDS and more specific treatment guidelines are required. © 2017 Wiley Periodicals, Inc.

Concepts: The Canon of Medicine, Surgery, Avicenna, Gastroenterology, Syndromes, Irritable bowel syndrome, Marfan syndrome, Ehlers-Danlos syndrome