Lung Arteriovenous Malformations Research Articles

Brain and lung arteriovenous malformation rescreening practices for children and adults with hereditary hemorrhagic telangiectasia

BackgroundPatients with hereditary hemorrhagic telangiectasia (HHT) are at risk for organ vascular malformations including arteriovenous malformations (AVMs) in the brain and lungs. North American HHT Centers of Excellence (CoEs) routinely screen for brain and lung AVMs, with the primary goal of detecting AVMs which can be treated before complications arise. Current international HHT guidelines provide recommendations for initial screening for brain and lung AVMs among children and adults with the disease, but rescreening recommendations are not comprehensively addressed and have not been reported. We determined current rescreening practices for brain and lung AVMs for children and adults with HHT among North American HHT CoEs.MethodsWe surveyed North American HHT CoEs regarding rescreening practices for new brain and lung AVMs in children and adults with initial negative screening.ResultsAll thirty CoEs responded; 28 regarding pediatric (93.3%) and 30 (100%) regarding adult HHT care. The median duration of practice experience in HHT was 11.5 (range 3–30) years for providers of pediatric HHT care and 11.5 (range 3–35) years for providers of adult HHT care. The median number of patients followed at each CoE was 60 for children (range 8–500) and 375 for adults (range 30–1500). 25/28 CoEs (89.3%) reported rescreening children for brain AVMs, most commonly with enhanced MRI (21/25, 84%). 25 CoEs rescreen children for lung AVMs, most commonly every 5 years (15/25). Only 4/30 CoEs (13.3%) rescreen adults for brain AVMs. 26/30 CoEs (86.7%) reported rescreening adults for lung AVMs, most commonly every 5 years (18/26, 69.2%).ConclusionsMost HHT CoEs routinely rescreen children for brain and lung AVMs and adults for lung AVMs when initial screening is negative, but adults are infrequently rescreened for brain AVMs. Long-term data regarding risk for new brain and lung AVMs are required to establish practice guidelines for rescreening.

Absence of renal phenotype in hereditary haemorrhagic telangiectasia.

Hereditary haemorrhagic telangiectasia is characterised by abnormal blood vessel formation, producing telangiectasia and arteriovenous malformations in multiple organs. Information regarding possible renal involvement in hereditary haemorrhagic telangiectasia is limited. This study assessed renal structure and function in 11 patients with genetically confirmed diagnosis and known arteriovenous malformations in lung, liver, gastrointestinal tract or brain. All had significant current or past epistaxis. Despite the vascularity of the kidneys, we found no evidence of renal involvement. This observation warrants further consideration.

Association of common candidate variants with vascular malformations and intracranial hemorrhage in hereditary hemorrhagic telangiectasia.

BackgroundHereditary hemorrhagic telangiectasia (HHT) is caused by mutations in TGFβ/BMP9 pathway genes and characterized by vascular malformations (VM) including arteriovenous malformations (AVM) in lung, liver, and brain, which lead to severe complications including intracranial hemorrhage (ICH) from brain VM. The clinical heterogeneity of HHT suggests a role for genetic modifier effects. Common variants in loci that modify phenotype severity in Tgfb knockout mice were previously reported as associated with lung AVM in HHT. Common variants in candidate genes were reported as associated with sporadic brain AVM and/or ICH. We investigated whether these variants are associated with HHT organ VM or with ICH from brain VM in 752 Caucasian HHT patients enrolled by the Brian Vascular Malformation Consortium.MethodsWe genotyped 11 candidate variants: four variants reported as associated with lung AVM in HHT (PTPN14 rs2936018, USH2A rs700024, ADAM17 rs12474540, rs10495565), and seven variants reported as associated with sporadic BAVM or ICH (APOE ε2, ANGPTL4 rs11672433, EPHB4 rs314308, IL6 rs1800795, IL1B rs1143627, ITGB8 rs10486391, TNFA rs361525). Association of genotype with any VM, lung AVM, liver VM, brain VM or brain VM ICH was evaluated by multivariate logistic regression adjusted for age, gender, and family clustering.ResultsNone of the 11 variants was significantly associated with any phenotype. There was a trend toward association of USH2A rs700024 with ICH (OR = 2.77, 95% CI = 1.13–6.80, p = .026).ConclusionWe did not replicate previously reported associations with HHT lung AVM and variants in Tgfb modifier loci. We also did not find significant associations between variants reported in sporadic brain AVM and VM or ICH in HHT.

Pulmonary Arteriovenous Malformations and Cerebral Abscess Recurrence in a Child With Hereditary Hemorrhagic Telangiectasia

A 17-year-old boy was referred to our center with a history of brain abscess (BA) recurring after 9 years. The patient reported 2 previous treatments for pulmonary arteriovenous malformations, sporadic nosebleeds, and familial history for epistaxis. Clinical investigations revealed arteriovenous malformations in lung, brain, and liver, as well as mucocutaneous telangiectases. A definite diagnosis of hereditary hemorrhagic telangiectasia was made based on clinical criteria and confirmed by genetic analysis. This is the first report of BA recurrence at the end of pediatric age. The present case and the literature review of all cases of BA thus far reported highlight the need to raise the suspicion of a pulmonary arteriovenous malformations, both isolated and in the context of a possible hereditary hemorrhagic telangiectasia, for any case of BA of unexplained etiology, in children as well as in adults.

Hereditary hemorrhagic telangiectasia: The purpose of a clinical case

Introduction: Hereditary hemorrhagic telangiectasia (HHT) or Rendu–Osler–Weber syndrome is a rare autosomal dominant disease, with a prevalence ranging from 1/5000 to 1/10,000 individuals, which causes a generalized fibrovascular dysplasia. While being asymptomatic in the newborn, this disease usually manifests itself in adolescence (62%) with recurrent epistaxis (90%), cutaneous telangiectasias between 20 and 40years (75%), manifestations of liver and lung arteriovenous malformations (AVM) (30 and 45%) and gastrointestinal bleeding (15%) after 40years, presenting neurological involvement in 8 to 20% of the patients.

The use of US health insurance data for surveillance of rare disorders: hereditary hemorrhagic telangiectasia

To assess the utility of US health insurance data for surveillance of hereditary hemorrhagic telangiectasia, an autosomal-dominant blood vasculature disorder with an estimated prevalence of 1.5-2.0 per 10,000 persons worldwide. We used 2005-2010 MarketScan Research Databases to identify individuals with employer-sponsored health insurance and International Classification of Disease, 9th Revision, Clinical Modification codes of 448.0 present in either one inpatient claim or two outpatient claims 30 days apart to define hereditary hemorrhagic telangiectasia. We examined frequencies of International Classification of Disease, 9th Revision, Clinical Modification codes for conditions that are complications of hereditary hemorrhagic telangiectasia among individuals with hereditary hemorrhagic telangiectasia and the general population to identify combinations of codes associated with hereditary hemorrhagic telangiectasia. Excluding observations from one state, the average prevalence of hereditary hemorrhagic telangiectasia was 0.3 per 10,000 persons. The reported prevalence rose with age from ~0.1 per 10,000 at ages <30 years to 1.0-1.1 per 10,000 at ages 70 years and above. The condition codes that were most specific to presumed hereditary hemorrhagic telangiectasia were lung arteriovenous malformations and upper gastrointestinal angiodysplasia. Combinations of those codes and codes for brain arteriovenous malformation and epistaxis were highly predictive of reporting of hereditary hemorrhagic telangiectasia, with 20-57% of enrollees with those codes also meeting the study definition for hereditary hemorrhagic telangiectasia. Hereditary hemorrhagic telangiectasia is underrecognized in US administrative data. Administrative health data can be used to identify individuals with combinations of signs that are suggestive of hereditary hemorrhagic telangiectasia. Studies are needed to test the hypothesis that referral for evaluation of individuals with administrative records suggestive of undiagnosed hereditary hemorrhagic telangiectasia could lead to diagnosis and access to life-saving treatments for both them and affected family members.

Local sclerotherapy with polydocanol (Aethoxysklerol®) for the treatment of Epistaxis in Rendu-Osler-Weber or Hereditary Hemorrhagic Telangiectasia (HHT): 15 years of experience

Hereditary Haemorrhagic Telangiectasia or Rendu-Osler-Weber syndrome is a rare autosomal dominant vascular disease characterized by mucocutaneous and gastrointestinal telangiectases and localized arteriovenous malformations in lung, brain and liver. Epistaxis, due to rupture of telangiectases of the nasal mucosa, is the most frequent clinical manifestation, leading in many cases to severe impairment of the quality of life in the patients. Though several treatments have been used to reduce epistaxis, none have been completely effective, with the exception of polydocanol (Aethoxysklerol®) in submucosal or subpericondrial injections, which was first presented in 2000 with very good results. After fifteen years using polydocanol in submucosal injections on 45 patients and with nearly 300 injections, we have observed that in 95% of all cases, their nose bleeds improved with respect to frequency and quantity without any important side effects. There was just one case of septal perforation, another with increased septal perforation, and one patient who suffered from dizziness and blurred vision for a few minutes. In this paper the results obtained using this technique over a fifteen-year period will be presented and evaluated.

Local sclerotherapy with polydocanol (Aethoxysklerol®) for the treatment of Epistaxis in Rendu-Osler-Weber or Hereditary Hemorrhagic Telangiectasia (HHT): 15 years of experience

Hereditary Haemorrhagic Telangiectasia or Rendu-Osler-Weber syndrome is a rare autosomal dominant vascular disease characterized by mucocutaneous and gastrointestinal telangiectases and localized arteriovenous malformations in lung, brain and liver. Epistaxis, due to rupture of telangiectases of the nasal mucosa, is the most frequent clinical manifestation, leading in many cases to severe impairment of the quality of life in the patients. Though several treatments have been used to reduce epistaxis, none have been completely effective, with the exception of polydocanol (Aethoxysklerol®) in submucosal or subpericondrial injections, which was first presented in 2000 with very good results. After fifteen years using polydocanol in submucosal injections on 45 patients and with nearly 300 injections, we have observed that in 95% of all cases, their nose bleeds improved with respect to frequency and quantity without any important side effects. There was just one case of septal perforation, another with increased septal perforation, and one patient who suffered from dizziness and blurred vision for a few minutes. In this paper the results obtained using this technique over a fifteen-year period will be presented and evaluated.

Novel mutations in the ENG and ACVRL1 genes causing hereditary hemorrhagic teleangiectasia

Hereditary haemorrhagic teleangiectasia (HHT) is an autosomal dominantly inherited disorder characterised by cutaneous and mucosal telangiectasias, epistaxis and arteriovenous malformations in lung, liver, central nervous system and gastrointestinal tract. Mutations in the genes for endoglin (ENG) and for activin A receptor type II-like kinase 1 (ACVRL1) have been identified to cause HHT. We performed molecular diagnosis in clinically affected probands of 52 HHT families and detected mutations in 34 cases. We report on a total of 19 novel disease-causing mutations, 7 in ENG and 12 in ACVRL1. Three of the novel mutations affected acceptor splice-sites in the ENG gene. RNA analyses in these three patients and in two further patients described before resulted in reduction of the transcript or in a shortened transcript. Furthermore, we identified a family with the mutation c.199C>T in the ACVRL1 gene with liver AVMs. This is the fifth family with this mutation and liver AVMs, clearly indicating a genotype-phenotype correlation for this mutation.

ALK-1 mutations in liver transplanted patients with hereditary hemorrhagic telangiectasia

Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominantly inherited disorder characterized by cutaneous and mucosal telangiectasias, epistaxis and arteriovenous malformations in lung, liver, central nervous system, and gastrointestinal tract. Mutations in the genes for endoglin (ENG) and for activin A receptor type II-like kinase 1 (ALK-1) have been identified to be associated with HHT. Intrahepatic manifestation in HHT might lead to the requirement of liver transplantation. We report here on 6 liver transplanted patients and 2 who were scheduled for liver transplantation due to intrahepatic HHT, in whom both genes were sequenced. Mutation analysis revealed in all patients the presence of mutations in ALK-1. In conclusion, these results are of possible prognostic value concerning the need of liver transplantation in HHT patients.

Brain abscesses associated with pulmonary arteriovenous malformations

We present three patients with brain abscesses who also had pulmonary arteriovenous malformations (AVMs). All patients had hereditary haemorrhagic telangiectasia (Osler's Disease). It is probable that the lung AVMs contributed to the development of the brain abscesses by allowing bacteria easier access to the systemic circulation through a right to left pulmonary vascular shunt, bypassing the filtering action of the pulmonary capillaries. In addition, one patient required a period of postoperative ventilation using PEEP, which may have exacerbated the shunt through the lung AVM and led to difficulty in weaning her from the ventilator.