More than meets the eye: Expanding and reviewing the clinical and mutational spectrum of brittle cornea syndrome.

Brittle cornea syndrome (BCS) is a rare autosomal recessive disorder characterized by corneal thinning and fragility, leading to corneal rupture, the main hallmark of this disorder. Non-ocular symptoms include not only hearing loss but also signs of connective tissue fragility, placing it in the Ehlers-Danlos syndrome (EDS) spectrum. It is caused by biallelic pathogenic variants in ZNF469 or PRDM5, which presumably encode transcription factors for extracellular matrix components. We report the clinical and molecular features of nine novel BCS families, four of which harbor variants in ZNF469 and five in PRDM5. We also performed a genotype- and phenotype-oriented literature overview of all (n = 85) reported patients with ZNF469 (n = 53) and PRDM5 (n = 32) variants. Musculoskeletal findings may be the main reason for referral and often raise suspicion of another heritable connective tissue disorder, such as kyphoscoliotic EDS, osteogenesis imperfecta, or Marfan syndrome, especially when a corneal rupture has not yet occurred. Our findings highlight the multisystemic nature of BCS and validate its inclusion in the EDS classification. Importantly, gene panels for heritable connective tissue disorders should include ZNF469 and PRDM5 to allow for timely diagnosis and appropriate preventive measures for this rare condition.

GRIN2B encephalopathy: novel findings on phenotype, variant clustering, functional consequences and treatment aspects.

BACKGROUND: We aimed for a comprehensive delineation of genetic, functional and phenotypic aspects of GRIN2B encephalopathy and explored potential prospects of personalised medicine. METHODS: Data of 48 individuals with de novo GRIN2B variants were collected from several diagnostic and research cohorts, as well as from 43 patients from the literature. Functional consequences and response to memantine treatment were investigated in vitro and eventually translated into patient care. RESULTS: Overall, de novo variants in 86 patients were classified as pathogenic/likely pathogenic. Patients presented with neurodevelopmental disorders and a spectrum of hypotonia, movement disorder, cortical visual impairment, cerebral volume loss and epilepsy. Six patients presented with a consistent malformation of cortical development (MCD) intermediate between tubulinopathies and polymicrogyria. Missense variants cluster in transmembrane segments and ligand-binding sites. Functional consequences of variants were diverse, revealing various potential gain-of-function and loss-of-function mechanisms and a retained sensitivity to the use-dependent blocker memantine. However, an objectifiable beneficial treatment response in the respective patients still remains to be demonstrated. CONCLUSIONS: In addition to previously known features of intellectual disability, epilepsy and autism, we found evidence that GRIN2B encephalopathy is also frequently associated with movement disorder, cortical visual impairment and MCD revealing novel phenotypic consequences of channelopathies.

Oral and mandibular manifestations in the Ehlers-Danlos syndromes.

The Ehlers-Danlos syndromes (EDS) are hereditary disorders that affect the connective tissue and collagen structures in the body. Several types of EDS have been identified. Oral and mandibular structures, which include oral soft tissue, dentition, facial and head pain, and the functioning of the temporomandibular joint (TMJ), are variably affected in the various types of EDS. These various manifestations of EDS have been noted for many years, but newer diagnostic techniques and studies are shedding additional light on the challenges faced by EDS patients in the area of oral and mandibular disorders. Further, the impact of temporomandibular disorder (TMD) on musculoskeletal dysfunction and vice versa, make this an important feature to recognize. Oral and mandibular hypermobility of the TMJ with associated consequences of EDS are noted. These features, diagnostic parameters and treatment procedures are presented. © 2017 Wiley Periodicals, Inc.

The international consortium on the Ehlers-Danlos syndromes.

Since 1998, two developments have led to concerns that the EDS nosology needs to be substantially revised. The first development was the clinical and molecular characterization of several new EDS variants, which substantially broadened the molecular basis underlying EDS. The second was the growing concern, in the absence of genetic diagnosis, that the hypermobile type of EDS had an expanded phenotype, may be genetically heterogeneous, and that the diagnostic criteria currently in use were inadequate. Furthermore, there is a dire need for the development of guidelines for management for each type of EDS to allow both the specialist and the generalist to care for affected individuals and their families. We have been meeting together as an international consortium over the past 2 years to establish these new criteria and management and care guidelines © 2017 Wiley Periodicals, Inc.

A framework for the classification of joint hypermobility and related conditions.

In the last decade, growing attention has been placed on joint hypermobility and related disorders. The new nosology for Ehlers-Danlos syndrome (EDS), the best-known and probably the most common of the disorders featuring joint hypermobility, identifies more than 20 different types of EDS, and highlights the need for a single set of criteria to substitute the previous ones for the overlapping EDS hypermobility type and joint hypermobility syndrome. Joint hypermobility is a feature commonly encountered in many other disorders, both genetic and acquired, and this finding is attracting the attention of an increasing number of medical and non-medical disciplines. In this paper, the terminology of joint hypermobility and related disorders is summarized. Different types of joint hypermobility, its secondary musculoskeletal manifestations and a simplified categorization of genetic syndromes featuring joint hypermobility are presented. The concept of a spectrum of pathogenetically related manifestations of joint hypermobility intersecting the categories of pleiotropic syndromes with joint hypermobility is introduced. A group of hypermobility spectrum disorders is proposed as diagnostic labels for patients with symptomatic joint hypermobility but not corresponding to any other syndromes with joint hypermobility. © 2017 Wiley Periodicals, Inc.

Hypermobile Ehlers-Danlos syndrome (a.k.a. Ehlers-Danlos syndrome Type III and Ehlers-Danlos syndrome hypermobility type): Clinical description and natural history.

The hypermobile type of Ehlers-Danlos syndrome (hEDS) is likely the most common hereditary disorder of connective tissue. It has been described largely in those with musculoskeletal complaints including joint hypermobility, joint subluxations/dislocations, as well as skin and soft tissue manifestations. Many patients report activity-related pain and some go on to have daily pain. Two undifferentiated syndromes have been used to describe these manifestations-joint hypermobility syndrome and hEDS. Both are clinical diagnoses in the absence of other causation. Current medical literature further complicates differentiation and describes multiple associated symptoms and disorders. The current EDS nosology combines these two entities into the hypermobile type of EDS. Herein, we review and summarize the literature as a better clinical description of this type of connective tissue disorder. © 2017 Wiley Periodicals, Inc.

Pain management in the Ehlers-Danlos syndromes.

Chronic pain in the Ehlers-Danlos syndromes (EDS) is common and may be severe. According to one study, nearly 90% of patients report some form of chronic pain. Pain, which is often one of the first symptoms to occur, may be widespread or localized to one region such as an arm or a leg. Studies on treatment modalities are few and insufficient to guide management. The following is a discussion of the evidence regarding the underlying mechanisms of pain in EDS. The causes of pain in this condition are multifactorial and include joint subluxations and dislocations, previous surgery, muscle weakness, proprioceptive disorders, and vertebral instability. Affected persons may also present with generalized body pain, fatigue, headaches, gastrointestinal pain, temporomandibular joint pain, dysmenorrhea, and vulvodynia. Pain management strategies may be focused around treating the cause of the pain (e.g., dislocation of a joint, proprioceptive disorder) and minimizing the sensation of pain. Management strategies for chronic pain in EDS includes physical therapy, medications, as well as durable medical equipment such as cushions, compressive garments, and braces. The different modalities are discussed in this paper. © 2017 Wiley Periodicals, Inc.

The 2017 international classification of the Ehlers-Danlos syndromes.

The Ehlers-Danlos syndromes (EDS) are a clinically and genetically heterogeneous group of heritable connective tissue disorders (HCTDs) characterized by joint hypermobility, skin hyperextensibility, and tissue fragility. Over the past two decades, the Villefranche Nosology, which delineated six subtypes, has been widely used as the standard for clinical diagnosis of EDS. For most of these subtypes, mutations had been identified in collagen-encoding genes, or in genes encoding collagen-modifying enzymes. Since its publication in 1998, a whole spectrum of novel EDS subtypes has been described, and mutations have been identified in an array of novel genes. The International EDS Consortium proposes a revised EDS classification, which recognizes 13 subtypes. For each of the subtypes, we propose a set of clinical criteria that are suggestive for the diagnosis. However, in view of the vast genetic heterogeneity and phenotypic variability of the EDS subtypes, and the clinical overlap between EDS subtypes, but also with other HCTDs, the definite diagnosis of all EDS subtypes, except for the hypermobile type, relies on molecular confirmation with identification of (a) causative genetic variant(s). We also revised the clinical criteria for hypermobile EDS in order to allow for a better distinction from other joint hypermobility disorders. To satisfy research needs, we also propose a pathogenetic scheme, that regroups EDS subtypes for which the causative proteins function within the same pathway. We hope that the revised International EDS Classification will serve as a new standard for the diagnosis of EDS and will provide a framework for future research purposes. © 2017 Wiley Periodicals, Inc.

Newborn Screening for Lysosomal Storage Disorders in Illinois: The Initial 15-Month Experience.

OBJECTIVES: To assess the outcomes of newborn screening for 5 lysosomal storage disorders (LSDs) in the first cohort of infants tested in the state of Illinois. STUDY DESIGN: Tandem mass spectrometry was used to assay for the 5 LSD-associated enzymes in dried blood spot specimens obtained from 219 973 newborn samples sent to the Newborn Screening Laboratory of the Illinois Department of Public Health in Chicago. RESULTS: The total number of cases with a positive diagnosis and the incidence for each disorder were as follows: Fabry disease, n = 26 (1 in 8454, including the p.A143T variant); Pompe disease, n = 10 (1 in 21 979); Gaucher disease, n = 5 (1 in 43 959); mucopolysaccharidosis (MPS) type 1, n = 1 (1 in 219 793); and Niemann-Pick disease type A/B, n = 2 (1 in 109 897). Twenty-two infants had a positive screen for 1 of the 5 disorders but could not be classified as either affected or unaffected after follow-up testing, including genotyping. Pseudodeficiencies for alpha-L-iduronidase and alpha-glucosidase were detected more often than true deficiencies. CONCLUSIONS: The incidences of Fabry disease and Pompe disease were significantly higher than published estimates, although most cases detected were predicted to be late onset. The incidences of Gaucher disease, MPS I, and Niemann-Pick disease were comparable with previously published estimates. A total of 16 infants could not be positively identified as either affected or unaffected. To validate the true risks and benefits of newborn screening for LSD, long term follow-up in these infants and those detected with later-onset disorders will be essential.

Spontaneous ruptured dissection of the right common iliac artery in a patient with classic Ehlers-Danlos syndrome phenotype.

Unlike vascular Ehlers-Danlos syndrome (EDS), classic EDS is rarely associated with vascular manifestation. We report the case of a 39-year-old man who presented with acute abdominal pain. At the time of presentation, the patient was in hypovolemic shock, and computed tomography angiogram demonstrated common iliac artery dissection with rupture. He underwent an attempted endovascular repair that was converted to an open repair of a ruptured right common iliac artery dissection. Subsequent genetic testing revealed a substitution of arginine for cysteine in type I collagen, COL1A1 exon 14 c.934C>T mutation, consistent with a rare variant of classic EDS.

Predictive value of fetal lung volume in prenatally diagnosed skeletal dysplasia.

OBJECTIVE: Pulmonary hypoplasia is a major cause of death in lethal skeletal dysplasias. We hypothesize that in fetuses with prenatally diagnosed skeletal dysplasia, comparison of observed-to-expected (O/E) lung volume will help predict lethality. STUDY DESIGN: We conducted a retrospective chart review of patients referred for evaluation of suspected fetal skeletal anomalies. Twenty-three pregnancies were identified with confirmed fetal diagnosis of skeletal dysplasia for which fetal magnetic resonance imaging (MRI) was performed between 21 and 38 weeks of gestation and ultrasound biometry data were available. Femur length to abdominal circumference ratio (FL/AC) and O/E lung volumes were calculated. The association between O/E lung volume, FL/AC, and lethality was measured using logistic regression. RESULTS: Lethality was significantly associated with O/E lung volume (p = 0.002) and FL/AC (p = 0.0476). Analysis with receiver-operating characteristic curves suggested that O/E lung volume of 47.9% or FL/AC of 0.124 could be useful clinical cutoffs in the prediction of lethality. CONCLUSION: In fetuses with skeletal dysplasia, fetal MRI-derived O/E lung volume was predictive of lethality. When evaluating a fetal skeletal dysplasia, fetal MRI may be considered in cases for which ultrasound-based lethality prediction is ambiguous or uncertain in order to provide families with the most complete and accurate information.

High prevalence of eosinophilic esophagitis in patients with inherited connective tissue disorders.

BACKGROUND: Eosinophilic esophagitis (EoE) is an emerging chronic inflammatory disease mediated by immune hypersensitization to multiple foods and strongly associated with atopy and esophageal remodeling. OBJECTIVE: We provide clinical and molecular evidence indicating a high prevalence of EoE in patients with inherited connective tissue disorders (CTDs). METHODS: We examined the rate of EoE among patients with CTDs and subsequently analyzed esophageal mRNA transcript profiles in patients with EoE with or without CTD features. RESULTS: We report a cohort of 42 patients with EoE with a CTD-like syndrome, representing 0.8% of patients with CTDs and 1.3% of patients with EoE within our hospital-wide electronic medical record database and our EoE research registry, respectively. An 8-fold risk of EoE in patients with CTDs (relative risk, 8.1; 95% confidence limit, 5.1-12.9; χ(2)1 = 112.0; P < 10(-3)) was present compared with the general population. Esophageal transcript profiling identified a distinct subset of genes, including COL8A2, in patients with EoE and CTDs. CONCLUSION: There is a remarkable association of EoE with CTDs and evidence for a differential expression of genes involved in connective tissue repair in this cohort. Thus, we propose stratification of patients with EoE and CTDs into a subset referred to as EoE-CTD.

Health Supervision for Children and Adolescents With Marfan Syndrome.

Marfan syndrome is a heritable connective tissue disorder that affects many different organ systems. In some cases, features of Marfan syndrome can be recognized at birth, but the majority will have manifestations that emerge throughout childhood and into adulthood. Significant morbidity and mortality are associated with this syndrome, and its features are best managed using a multidisciplinary approach. This clinical report is designed to assist the pediatrician in recognizing the features of Marfan syndrome as well as caring for the individual with Marfan syndrome to maximize their health and quality of life.

Pediatric joint hypermobility: a diagnostic framework and narrative review.

BACKGROUND: Hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobility spectrum disorders (HSD) are debilitating conditions. Diagnosis is currently clinical in the absence of biomarkers, and criteria developed for adults are difficult to use in children and biologically immature adolescents. Generalized joint hypermobility (GJH) is a prerequisite for hEDS and generalized HSD. Current literature identifies a large proportion of children as hypermobile using a Beighton score ≥ 4 or 5/9, the cut off for GJH in adults. Other phenotypic features from the 2017 hEDS criteria can arise over time. Finally, many comorbidities described in hEDS/HSD are also seen in the general pediatric and adolescent population. Therefore, pediatric specific criteria are needed. The Paediatric Working Group of the International Consortium on EDS and HSD has developed a pediatric diagnostic framework presented here. The work was informed by a review of the published evidence. OBSERVATIONS: The framework has 4 components, GJH, skin and tissue abnormalities, musculoskeletal complications, and core comorbidities. A Beighton score of ≥ 6/9 best identifies children with GJH at 2 standard deviations above average, based on published general population data. Skin and soft tissue changes include soft skin, stretchy skin, atrophic scars, stretch marks, piezogenic papules, and recurrent hernias. Two symptomatic groups were agreed: musculoskeletal and systemic. Emerging comorbid relationships are discussed. The framework generates 8 subgroups, 4 pediatric GJH, and 4 pediatric generalized hypermobility spectrum disorders. hEDS is reserved for biologically mature adolescents who meet the 2017 criteria, which also covers even rarer types of Ehlers-Danlos syndrome at any age. CONCLUSIONS: This framework allows hypermobile children to be categorized into a group describing their phenotypic and symptomatic presentation. It clarifies the recommendation that comorbidities should be defined using their current internationally accepted frameworks. This provides a foundation for improving clinical care and research quality in this population.

The role of functional disability and social support in psychological outcomes for individuals with pediatric hypermobile ehlers-danlos syndrome.

Hypermobile Ehlers-Danlos syndrome (hEDS) includes physical symptoms of chronic pain, fatigue, gastrointestinal dysfunction, and joint subluxations/dislocations. This study aims to fill a research gap regarding the psychosocial well-being in pediatric hEDS by assessing relationships between functional disability, social support, and mental health. Increased functional disability is hypothesized to be associated with increased mental health challenges, specifically anxiety and depression, and general social support is hypothesized to moderate this relationship, such that higher perceived social support will mitigate the negative psychological impacts of functional disability. Gender's influence on mental health in pediatric hEDS is also explored. Thirty-four youth with pediatric hEDS recruited from a United States Midwest multidisciplinary genetics clinic completed self-report questionnaires. Results demonstrate associations between functional disability and mental health, and social support and mental health independently; however, moderation was not found. Functional disability and social support each have a unique influence on the mental health of children with pediatric hEDS and should each receive clinical attention. Exploratory analyses into the influence of gender provide a groundwork for future studies.

Cross-sectional and longitudinal assessment of aortic root dilation and valvular anomalies in hypermobile and classic Ehlers-Danlos syndrome.

OBJECTIVES: To delineate the prevalence of cardiac findings in hypermobile and classic Ehlers-Danlos syndrome and provide longitudinal analysis of aortic root growth. STUDY DESIGN: A retrospective chart review was conducted, and data were analyzed for cross-sectional prevalence of aortic dilation and valvular anomalies. The clinical implications of aortic root growth were determined by assessment of progression of aortic root measurements over time and clinical symptoms. RESULTS: Patients whose first echocardiogram was obtained in late childhood or adulthood were less likely to have aortic dilation (P < .002) than those whose first echocardiogram was obtained in early childhood. Longitudinally, seven individuals had dilated aortas before age 14, and only one individual continued to show dilation after age 14 (P = .0143). No patient with a normal aortic root in childhood had development of dilation in adulthood. Fifteen of the 252 patients (6.0%) had mitral valve prolapse (MVP), although only one patient (0.4%) had MVP that was mild to moderate. CONCLUSIONS: Although aortic root size and MVP are increased in patients with these types of Ehlers-Danlos syndrome, they tend to be of little clinical consequence. Echocardiography may still be warranted as part of cardiovascular assessment, but decreased frequency of screening is recommended especially in symptom-free adults.

Variable expression of neurofibromatosis 1 in monozygotic twins.

Neurofibromatosis 1 (NF1) is a common autosomal dominant disorder with high penetrance but extreme variability of expression. Monozygotic (MZ) twins with NF1 who have phenotypic discordances are a useful tool in evaluating which traits are influenced by non-hereditary influences such as second hit somatic events, environmental agents, epigenetic modification, or post-zygotic mutations. We evaluated nine sets of MZ twins and one set of MZ triplets, ages 4-18 years, for NF1 features and calculated probandwise concordance (P(C)) for each feature. MZ twins were highly concordant in numbers of café-au-lait spots (P(C) = 0.89) and cutaneous neurofibromas. IQ scores were within 10 points for all twin pairs tested, and similar patterns of learning disabilities and speech disorders were observed. Twin pairs showed significant discordance for tumors, particularly plexiform neurofibromas (P(C) = 0.40) and malignant peripheral nerves sheath tumors (MPNST), as expected if post-natal second-hit events were contributing to these features. One set of twins was concordant for multiple, large paraspinal neurofibromas, suggesting that there may be more hereditary factors involved in production of paraspinal neurofibromas. Four sets were concordant for pectus deformities of the chest (P(C) = 0.80). Three sets of twins were discordant for scoliosis (P(C) = 0.40); an additional set was concordant for scoliosis but differed in presence of dystrophic features and need for surgery. Our data suggest there are additional non-hereditary factors modifying the NF1 phenotype and causing discordancies between MZ twins. Future studies may focus on differences in epigenetic changes or somatic mosaicism which have been documented for other disease genes in MZ twins.