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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a rare case of recurrent brain abscess associated with congenital pulmonary arteriovenous fistula. A 52-year-old man was admitted to our hospital in October, 1999 because of a sudden stroke-like onset of right hemiparesis, right hemiparesthesia, dysarthria and sensory aphasia. He had a history of previous brain abscess in the right cerebellar hemisphere. It had been removed in 1991. CT scan at the time of the current admission disclosed a low-density area in the left parietal region. The mass was ring-enhanced after injection of contrast medium. On MRI the mass lesion was depicted as low-intensity on T1-weighted image and high-intensity on T2-weighted image. The mass was ring-enhanced after administration of Gd-DTPA. In spite of conservative treatment the size of the abscess increased considerably with marked surrounding edema. The brain abscess was successfully treated with aspiration and drainage, and the residual mass was resected. The patient also had a history of arteriovenous fistula in the lower lobe of his right lung. This had been excised in 1965. However, he had no signs, symptoms or family histories of hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease). Contrast enhanced CT scan of the chest showed nodular lesions connected to vascular shadows in the right lower lung field. Pulmonary angiograms also revealed multiple arteriovenous fistulas in the lower lobe of the right lung. He was not dyspneic or cyanotic, but his hypoxia, polycythemia, and recurrent brain abscess were thought to be caused by pulmonary arteriovenous fistula. The fistulas were embolized with coils via a percutaneous catheter. Pulmonary arteriovenous fistula should be treated aggressively either by surgery and/or by coil embolization in order to prevent the complication of brain abscess.
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PMID:[Recurrent brain abscess associated with congenital pulmonary arteriovenous fistula: a case report]. 1497 25

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease of the vascular connective tissue. Pulmonary arteriovenous and cerebral vascular malformations are risk factors for serious neurological complications such as paradoxical embolism and intracranial hematomas. We describe two patients with HHT and pulmonary arteriovenous malformations suffering from stroke caused by paradoxical embolism. In both cases, fistulas were successfully treated by embolisation and no further cerebral ischemic events occurred. In ischemic strokes of unknown origin, HHT should be considered as a possible diagnosis with effective treatment options.
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PMID:[Hereditary hemorrhagic telangiectasia. A rare treatable cause of stroke]. 1563 May 98

Hereditary Haemorrhagic Telangiectasia, or Rendu-Osler-Weber syndrome, is a rare autosomal dominant disorder involving the vascular system and is characterised by a highly variable expressivity and age-dependent penetrance. Diagnosis is based on the presence of at least three of four of the following symptoms: spontaneous epistaxis, cutaneous telangiectases, arteriovenous malformations in internal organs and familiarity. Recurrent complications are severe anaemia, stroke, portal and pulmonary hypertension. The peculiar characteristic of this disease is the diffusion of arteriovenous malformations, that is, localised abnormal arteriovenous connections affecting both microvasculature and large vessels. HHT is actually a heterogenous genetic disorder, divided into two clinically indistinguishable forms: HHT1 caused by mutations in endoglin gene mapping on chromosome 9q, and HHT2 caused by mutations in ALK1 located on chromosome 12q. Haploinsufficiency is the underlying mechanism for endoglin and most ALK1 mutations. Such mutations lead to a deficiency in angiogenesis, i.e. the sprouting of new vessels from pre-existing ones. To date, little is still known about the mechanism(s) responsible for lesion formation, development and slow growth. Current models focus on the role that TGF-beta superfamily members, a vast group of multifunctional cytokines, play in endothelial responses to angiogenic stimuli. As both genes seem to act in TGF-beta signal transduction pathways, SMAD proteins are also thought to be involved. There is no clear explanation accounting for the strong variability shown even among members of the same family despite the sharing of the same disease-causing mutation, and why lesions are spatially discrete.
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PMID:Hereditary Haemorrhagic Telangiectasia (HHT): genetic and molecular aspects. 1661 Oct 99

In the last years, the understanding of HHT has greatly progressed. The two genes for most on cromosomes 9 and 12 have been discovered and the existence of a third involved gene has been predicted. Recent progress in the field of genetics has allowed the identification of many gene mutation thus facilitating the characterisation of the at risk members of the same family. Complications from bleeding or shunting (pulmonary AVMs) may be sudden and life-threatening (hemothorax, haemoptysis, stroke and brain abscess). Catastrophic events are preventable by early diagnosis and treatment. Appropriate screening programmes are mandatory and multi-specialistic cooperation is needed. Special centers have been developed in the world, where physicians, who are specialised and trained in all aspects of HHT, are working to develop better therapeutic approaches for the disease and to locate new genes in view of the future potential of gene therapy for this condition.
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PMID:The need for an interdisciplinary network of investigations on HHT. 1661 Nov 7

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder characterized by epistaxis, telangiectasia, and visceral vascular manifestations. Infectious and ischemic central nervous system (CNS) manifestations due to embolism through pulmonary arteriovenous malformations (PAVMs) represent the main causes of morbidity. To improve the phenotypic characterization of HHT with PAVM, we conducted a retrospective multicenter study of patients with HHT and at least 1 PAVM detected by chest computed tomography (CT) and/or pulmonary angiography, with particular attention to CNS and infectious manifestations. The study included 126 patients (47 men, 79 women), with a mean age of 43.1 +/- 17.4 years; 45 patients had a mutation of the ENG gene and 16 had a mutation of ACVRL1. PAVMs were diagnosed as a result of systematic screening procedures (29%), incidental imaging findings (15%), dyspnea (22%), or CNS symptoms (13%). The PAVMs were diagnosed at a mean age of 43 +/- 17 years, with a linear distribution of diagnosis between 20 and 75 years. Dyspnea on exertion was present in 56% of patients. Four patients had a hemothorax, including 1 during pregnancy. Fifty-three CNS events directly related to HHT (excluding migraine) were observed in 35% of patients: cerebral abscess (19.0%), ischemic cerebral stroke (9.5%), transient cerebral ischemic attack (6.3%), and cerebral hemorrhage (2.4%). The median age of onset was 33 years for cerebral abscesses (range, 11-66 yr), and 53.5 years for ischemic cerebral events (range, 2-72 yr). Migraine was reported in 16% of patients. The diagnoses of PAVM and HHT were made at the time of the cerebral abscess in 13 cases (54%). Forty-three percent of patients were hypoxemic at rest. Contrast echocardiography showed intrapulmonary right-to-left shunting in 87% of tested patients. PAVMs were seen on chest radiograph in 54% of patients, and on the CT scan in all patients. One hundred five patients (83%) underwent treatment of the PAVM, by percutaneous embolization (71%) and/or by surgical resection (23%). A high frequency of CNS and infectious complications was observed in this large series of patients with HHT-related PAVM. Physicians may not be sufficiently aware of the clinical manifestations of this orphan disorder. Patients diagnosed with HHT should be informed by physicians and patient associations of the risk of PAVM-related complications, and systematic screening for PAVM should be proposed, regardless of a patient's symptoms, familial history, or genetic considerations.
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PMID:Pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: a series of 126 patients. 1722 Jul 51

Hereditary hemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease is a genetic disorder with autosomal dominance and variable penetrance, characterized by epistaxis, telangiectasia and visceral manifestations of the disease. The estimated minimal prevalence is 1/10,000 inhabitants. The diagnosis is established on clinical criteria, and may be further confirmed by the identification of causative mutations in either the ENG or the ACVRL1 gene coding for endoglin and ALK1, respectively. Pulmonary vascular manifestations of HHT include pulmonary arteriovenous malformations (PAVMs; especially in patients with ENG mutations) and less frequently pulmonary hypertension (especially in patients with ACVRL1 mutations). In 15-33% of patients with HHT, PAVMs consist of abnormal communications between pulmonary arteries and pulmonary veins, causing right-to-left shunting, and thus, frequently hypoxemia and dyspnea on exertion, although PAVMs may remain asymptomatic and frequently undiagnosed unless complications occur. PAVMs result in severe and frequent complications often at a young age, which may reveal the diagnosis, e.g. transient ischemic attack and cerebral stroke (10-19% of patients), systemic severe infections and abscesses (including cerebral abscess in 5-19% of patients), and rarely massive hemoptysis or hemothorax. Infections in HHT are related to the right-to-left shunting that bypasses the pulmonary capillaries and facilitates the passage of septic or aseptic emboli into the systemic and especially cerebral circulation, and potentially to minor defects in innate immunity. Treatment of PAVMs based on transcatheter coil vaso-occlusion of the feeding artery significantly decreases right-to-left shunting, hypoxemia and dyspnea on exertion, and reduces the risk of systemic complications. Long-term follow-up is warranted after transcatheter vaso-occlusion of PAVMs due to frequent recanalization of treated PAVMs and development or growth of untreated PAVMs. Patients with HHT should be informed of the risk of PAVM and potentially severe complications occurring in heretofore asymptomatic subjects. All adult patients with HHT should be proposed systematic screening for PAVM, by contrast echocardiography (preceded by anteroposterior chest radiograph) or computed tomography of the chest. Pulmonary hypertension is rare in HHT, and may be due either to systemic arteriovenous shunting in the liver increasing cardiac output or be clinically and histologically indistinguishable from idiopathic pulmonary arterial hypertension. Pulmonary hypertension is detected by systematic examination of right cardiac cavities and tricuspid regurgitation flow at echocardiography, and the diagnosis is established by right heart catheterization.
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PMID:Pulmonary vascular manifestations of hereditary hemorrhagic telangiectasia (rendu-osler disease). 1764 82

Hereditary hemorrhagic telangectasia (HHT), also known as Osler-Weber-Rendu disease, is an autosomal dominant vascular dysplasia with high penetrance and variable expressivity. A wide variety of neurological complications have been reported in association with this condition. We report the first case of spinal cord infarction likely due to paradoxical embolization with HHT and review the literature on the neurological complications of this disorder. MEDLINE was employed to identify all published reports of HHT with neurological complications. We identified 44 references with a total of 436 cases of neurological complications of HHT. The most common complication was ischemic stroke and the main etiology for the vascular neurological complications in patients with HHT was pulmonary arteriovenous malformation. HHT should be considered in the differential diagnosis of any patient with cutaneous or mucosal telangiectasia or a history of unexplained epistaxis. HHT is associated with a diverse array of neurological disorders; most commonly ischemic and hemorrhagic stroke, transient ischemic attack, and brain abscess. While myelopathy secondary to arteriovenous malformation with HHT has been previously reported, this is the first instance of spinal cord infarction due to paradoxical embolization in this disorder.
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PMID:Hereditary hemorrhagic telangectasia and spinal cord infarct: case report with a review of the neurological complications of HHT. 1830 27

Rendu-Osler-Weber syndrome is an autosomal dominant disorder characterized by multiple skin and mucosal telangiectasis and multiorgan arteriovenous malformations. Neurological manifestations may occur because of cerebral arteriovenous malformations, intracranial hemorrhage, and most commonly by ischemic stroke and brain abscess secondary to paradoxical embolization in patients with pulmonary arteriovenous malformations. Intramedullary abscess is a rare, unusual condition, in Rendu-Osler-Weber syndrome. We report the case of a 56 years old woman, with a familial history of Rendu-Osler-Weber syndrome, admitted to intensive care with acute quadriplegia and hypoxemia. Our diagnosis was pulmonary arteriovenous malformations and intramedullary abscess.
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PMID:[Spinal abscess in a patient with hereditary hemorrhagic telangiectasia]. 1842 64

Rendu-Osler-Weber syndrome (hereditary haemorrhagic telangiectasia) is a vascular dysplasia characterized by recurrent epistaxis, mucocutaneous telangiectasia and a family history of the disorder. Although rare, it may cause significant morbidity to healthy and young individuals. We report three cases highlighting the cerebral manifestations of this disorder. These cases include cerebral abscess, cerebral haemorrhage and embolic stroke. These cerebral manifestations are due to complications associated with pulmonary arteriovenous fistulae or cerebral vascular malformations. The current management and screening for this disorder are reviewed.
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PMID:Rendu-Osler-Weber syndrome: a current perspective on cerebral manifestations. 1863 47

Brain arteriovenous malformations (BAVMs) are an important cause of intracerebral hemorrhage (ICH) in young adults. Biological predictors of future ICH risk are lacking, and controversy exists over previous studies of natural history risk among predominantly ruptured BAVM cohorts. Recent studies have suggested that the majority of BAVMs are now diagnosed as unruptured lesions, and that the risk according to natural history among these lesions may be less than previously assumed. In the first part of this review, the authors discuss available data on the natural history of BAVMs and highlight the need for future studies that aim to develop surrogate biomarkers of disease progression that accurately predict future risk of ICH in BAVMs. The etiology of BAVM remains unknown. Recent studies have suggested a role for genetic factors in the pathogenesis of sporadic BAVM, which is further supported by reports of familial occurrence of BAVM and association with known systemic genetic disorders (such as Osler-Weber-Rendu disease, Sturge-Weber disease, and Wyburn-Mason syndrome). Molecular characterization of BAVM tissue demonstrates a highly angiogenic milieu with evidence of increased endothelial cell turnover. Taken together with a number of reports of de novo BAVM formation, radiographic growth after initial BAVM diagnosis, and regrowth after successful treatment of BAVM, these findings challenge the long-held assumption that BAVMs are static lesions of congenital origin. In the second part of this review, the authors discuss available data on the origins of BAVM and offer insights into future investigations into genetics and endothelial progenitor cell involvement in the pathogenesis of BAVM. Current treatment options for BAVM focus on removal or obliteration of the lesion in an attempt to protect against future ICH risk, including microsurgical resection, endovascular embolization, and stereotactic radiosurgery (SRS). In the third part of this review, the authors discuss available data on SRS in BAVMs and highlight the need for future studies on the radiobiology of BAVMs, especially in regard to biomarker detection for tracking SRS response during the latency period. Insights from future investigations in BAVM may not only prove important for the development of novel therapies and relevant biomarkers for BAVM, but could also potentially benefit a variety of other disorders involving new vessel formation in the CNS, including stroke, tumors, moyamoya disease, and other cerebrovascular malformations.
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PMID:Pathogenesis and radiobiology of brain arteriovenous malformations: implications for risk stratification in natural history and posttreatment course. 1940 10


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