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Concept: Ehlers-Danlos syndrome

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Ehlers-Danlos syndromes (EDS) are a heterogeneous group of heritable connective tissue disorders. Gastrointestinal manifestations in EDS have been described but their frequency, nature and impact are poorly known. We aimed to assess digestive features in a national cohort of EDS patients.

Concepts: Life, Collagen, Connective tissue, Ehlers-Danlos syndrome

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Generalized joint hypermobility (GJH) is highly prevalent among patients diagnosed with chronic pain. When GJH is accompanied by pain in ≥4 joints over a period ≥3 months in the absence of other conditions that cause chronic pain, the hypermobility syndrome (HMS) may be diagnosed. In addition, GJH is also a clinical sign that is frequently present in hereditary diseases of the connective tissue, such as the Marfan syndrome, osteogenesis imperfecta, and the Ehlers-Danlos syndrome. However, within the Ehlers-Danlos spectrum, a similar subcategory of patients having similar clinical features as HMS but lacking a specific genetic profile was identified: Ehlers-Danlos syndrome hypermobility type (EDS-HT). Researchers and clinicians have struggled for decades with the highly diverse clinical presentation within the HMS and EDS-HT phenotypes (Challenge 1) and the lack of understanding of the pathological mechanisms that underlie the development of pain and its persistence (Challenge 2). In addition, within the HMS/EDS-HT phenotype, there is a high prevalence of psychosocial factors, which again presents a difficult issue that needs to be addressed (Challenge 3). Despite recent scientific advances, many obstacles for clinical care and research still remain. To gain further insight into the phenotype of HMS/EDS-HT and its mechanisms, clearer descriptions of these populations should be made available. Future research and clinical care should revise and create consensus on the diagnostic criteria for HMS/EDS-HT (Solution 1), account for clinical heterogeneity by the classification of subtypes within the HMS/EDS-HT spectrum (Solution 2), and create a clinical core set (Solution 3).

Concepts: Collagen, Syndromes, Marfan syndrome, Genetic disorders, Connective tissue, Ehlers-Danlos syndrome, Hypermobility, Diseases involving the fasciae

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: The authors hypothesized that variants within genes, such as COL5A1, COL3A1, COL6A1, and COL12A1, that code for connective tissue components of the musculoskeletal system may modulate susceptibility to exercise-associated muscle cramping (EAMC). Specifically, the aim of this study was to investigate if the COL5A1 rs12722 (C/T), COL3A1 rs1800255 (G/A), COL6A1 rs35796750 (T/C), and COL12A1 rs970547 (A/G) polymorphisms are associated with a history of EAMC.

Concepts: DNA, Bone, Blood, Collagen, Muscle, Tissues, Connective tissue, Ehlers-Danlos syndrome

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Many non-musculoskeletal complaints in EDS-HT may be related to dysautonomia. This study therefore aims to investigate whether dysautonomia is present and to explore the underlying mechanisms.

Concepts: Syndromes, Marfan syndrome, Ehlers-Danlos syndrome

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We aimed to assess the frequency of connective tissue abnormalities among patients with cerebrospinal fluid (CSF) leaks in a prospective study using a large cohort of patients. We enrolled a consecutive group of 50 patients, referred for consultation because of CSF leak. All patients have been carefully examined for the presence of connective tissue abnormalities, and based on findings, patients underwent genetic testing. Ancillary diagnostic studies included echocardiography, eye exam, and histopathological examinations of skin and dura biopsies in selected patients. We identified nine patients with heritable connective tissue disorders, including Marfan syndrome, Ehlers-Danlos syndrome and other unclassified forms. In seven patients, spontaneous CSF leak was the first noted manifestation of the genetic disorder. We conclude that spontaneous CSF leaks are associated with a spectrum of connective tissue abnormalities and may be the first noted clinical presentation of the genetic disorder. We propose that there is a clinical basis for considering spontaneous CSF leak as a clinical manifestation of heritable connective tissue disorders, and we suggest that patients with CSF leaks should be screened for connective tissue and vascular abnormalities.

Concepts: Genetics, Collagen, Marfan syndrome, Genetic disorders, Pneumothorax, Connective tissue, Ehlers-Danlos syndrome, Spontaneous cerebrospinal fluid leak

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Postural tachycardia syndrome (POTS) is defined by a heart rate increment of 30 beats/min or more within 10 minutes of standing or head-up tilt in the absence of orthostatic hypotension; the standing heart rate is often 120 beats/min or higher. POTS manifests with symptoms of cerebral hypoperfusion and excessive sympathoexcitation. The pathophysiology of POTS is heterogeneous and includes impaired sympathetically mediated vasoconstriction, excessive sympathetic drive, volume dysregulation, and deconditioning. POTS is frequently included in the differential diagnosis of chronic unexplained symptoms, such as inappropriate sinus tachycardia, chronic fatigue, chronic dizziness, or unexplained spells in otherwise healthy young individuals. Many patients with POTS also report symptoms not attributable to orthostatic intolerance, including those of functional gastrointestinal or bladder disorders, chronic headache, fibromyalgia, and sleep disturbances. In many of these cases, cognitive and behavioral factors, somatic hypervigilance associated with anxiety, depression, and behavioral amplification contribute to symptom chronicity. The aims of evaluation in patients with POTS are to exclude cardiac causes of inappropriate tachycardia; elucidate, if possible, the most likely pathophysiologic basis of postural intolerance; assess for the presence of treatable autonomic neuropathies; exclude endocrine causes of a hyperadrenergic state; evaluate for cardiovascular deconditioning; and determine the contribution of emotional and behavioral factors to the patient’s symptoms. Management of POTS includes avoidance of precipitating factors, volume expansion, physical countermaneuvers, exercise training, pharmacotherapy (fludrocortisone, midodrine, β-blockers, and/or pyridostigmine), and behavioral-cognitive therapy. A literature search of PubMed for articles published from January 1, 1990, to June 15, 2012, was performed using the following terms (or combination of terms): POTS; postural tachycardia syndrome, orthostatic; orthostatic; syncope; sympathetic; baroreceptors; vestibulosympathetic; hypovolemia; visceral pain; chronic fatigue; deconditioning; headache; Chiari malformation; Ehlers-Danlos; emotion; amygdala; insula; anterior cingulate; periaqueductal gray; fludrocortisone; midodrine; propranolol; β-adrenergic; and pyridostigmine. Studies were limited to those published in English. Other articles were identified from bibliographies of the retrieved articles.

Concepts: Hypertension, Cardiology, Orthostatic hypotension, Vasoconstriction, Postural orthostatic tachycardia syndrome, Ehlers-Danlos syndrome, Arnold-Chiari malformation, Orthostatic intolerance

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We report on an autosomal-recessive variant of Ehlers-Danlos syndrome (EDS) characterized by severe muscle hypotonia at birth, progressive scoliosis, joint hypermobility, hyperelastic skin, myopathy, sensorineural hearing impairment, and normal pyridinoline excretion in urine. Clinically, the disorder shares many features with the kyphoscoliotic type of EDS (EDS VIA) and Ullrich congenital muscular dystrophy. Linkage analysis in a large Tyrolean kindred identified a homozygous frameshift mutation in FKBP14 in two affected individuals. Based on the cardinal clinical characteristics of the disorder, four additional individuals originating from different European countries were identified who carried either homozygous or compound heterozygous mutations in FKBP14. FKBP14 belongs to the family of FK506-binding peptidyl-prolyl cis-trans isomerases (PPIases). ER-resident FKBPs have been suggested to act as folding catalysts by accelerating cis-trans isomerization of peptidyl-prolyl bonds and to act occasionally also as chaperones. We demonstrate that FKBP14 is localized in the endoplasmic reticulum (ER) and that deficiency of FKBP14 leads to enlarged ER cisterns in dermal fibroblasts in vivo. Furthermore, indirect immunofluorescence of FKBP14-deficient fibroblasts indicated an altered assembly of the extracellular matrix in vitro. These findings suggest that a disturbance of protein folding in the ER affecting one or more components of the extracellular matrix might cause the generalized connective tissue involvement in this disorder. FKBP14 mutation analysis should be considered in all individuals with apparent kyphoscoliotic type of EDS and normal urinary pyridinoline excretion, in particular in conjunction with sensorineural hearing impairment.

Concepts: Mutation, Collagen, Endoplasmic reticulum, Marfan syndrome, Tinnitus, Connective tissue, Ehlers-Danlos syndrome, Hypermobility

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Ehlers-Danlos syndrome (EDS) type VIII (periodontitis type) is a distinct form of EDS characterized by periodontal disease leading to precocious dental loss and a spectrum of joint and skin manifestations. EDS type VIII is transmitted in an autosomal dominant pattern; however, the mutated gene has not been identified. There are insufficient data on the spectrum of clinical manifestations and natural history of the disorder, and only a limited number of patients and pedigrees with this condition have been reported. We present a four-generation EDS type VIII kindred and show that EDS VIII is clinically variable and although some cases lack the associated skin and joint manifestations, microscopic evidence of collagen disorganization is detectable.We further propose that the diagnosis of EDS type VIII should be considered in familial forms of periodontitis, even when the associated skin and joint manifestations are unconvincing for the diagnosis of a connective tissue disorder. This novel observation highlights the uncertainty of using connective tissue signs in clinical practice to diagnose EDS type VIII.

Concepts: Bone, Collagen, Gingiva, Marfan syndrome, Connective tissue, Periodontitis, Periodontal disease, Ehlers-Danlos syndrome

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EDS-HT is a connective tissue disorder characterized by large inter-individual differences in the clinical presentation, complicating diagnosis and treatment. We aim to describe the clinical heterogeneity and to investigate whether differences in the symptom profile are also reflected as disparity in functional impairment and pain experience. In this study, 78 patients were asked to describe their symptoms due to EDS-HT. Next, a hierarchical cluster analysis was performed using the Jaccard measure of similarity to assess whether subgroups could be distinguished based on the symptoms reported. This analysis yielded 3 clusters of participants with distinct complaint profiles. The key differences were found in the domain of non-musculoskeletal complaints, which was significantly larger in cluster 2. Furthermore, cluster 2 was characterized by a worse physical and psychosocial health, a higher pain severity and a larger pain interference in daily life. The results emphasize that non-musculoskeletal symptoms are an important complication of EDS-HT, as the number of these complaints was found to be a significant predictor for both functional health status (SIP) and pain experience (MPI). In conclusion, this study confirms that EDS-HT is a heterogeneous entity and encourages the clinician to be more aware of the large variety of EDS-HT symptoms, in order to improve disease recognition and to establish more tailored treatment strategies.

Concepts: Cluster analysis, Disease, Collagen, Heterogeneity, Marfan syndrome, Connective tissue, Ehlers-Danlos syndrome, Hypermobility

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Vascular (type IV) Ehlers-Danlos is an autosomally dominant inherited condition that results from a defect in type III collagen production. It can result in vascular complications such as rupture and dissection, as well as gastrointestinal and uterine rupture. We present the case of a 17-year-old girl who presented with transient neurological signs and pulsatile tinnitus secondary to carotid dissection 1 year after suffering from a stroke caused also by a carotid dissection on the contralateral side. We managed acutely and investigated for an underlying connective tissue disorder. Genetic analysis of COL 3A1 was performed and a heterozygous missense, non-conservative mutation of c.970G>A was detected. This replication mutation has previously been associated with type IV Ehlers-Danlos syndrome.

Concepts: Bone, Blood, Biology, Collagen, Aspirin, Marfan syndrome, Connective tissue, Ehlers-Danlos syndrome