Manifestations Of Hereditary Hemorrhagic Telangiectasia Research Articles

Pulmonary arterio-venous malformations in a patient with a novel mutation in exon 10 of the ACVRL1 gene

Mutations of the ACVRL1 gene are a cause of hereditary haemorrhagic telangiectasia (HHT) type 2. In this case report, we present a patient with isolated pulmonary arterio-venous malformations (PAVMs) without other diagnostic criteria for HHT and a novel mutation in exon 10 of the ACVRL1 gene. Other mutations in exon 10 of ACVRL1 have been linked to the development of pulmonary artery hypertension, but PAVMs are a rare manifestation of HHT associated with ACVRL1 mutations. A disrupted endothelial TGF-beta/BMP signaling cascade underlies the pathogenesis of HHT, but the exact mechanism of the disease remains unelucidated. In particular, the factors that influence the variable clinical presentation are not fully understood.

Treatment of the skin manifestations of hereditary hemorrhagic telangiectasia with pulsed dye laser

Hereditary hemorrhagic telangiectasia (HHT) is a familial disorder, in which variably sized arteriovenous malformations develop in the skin, respiratory tract, central nervous system, and gastrointestinal and urogenital tracts. Bleeding is a major problem in the abnormal vessels, primarily in the nose and internal lesions. Skin lesions, in contrast, do not generally bleed spontaneously but pose a significant cosmetic concern. The lesions are characteristically small caliber vessels located in the dermis. As such, they are ideal targets for vascular lesions. Eight patients with cutaneous facial lesions of HHT were treated by pulsed dye laser. All patients exhibited excellent (75-100%) clearance after a mean of 2.6 treatments (range 1-8). In comparison, a control group of patients with non-HHT facial telangiectasia required a mean of 1.9 (range 1-5; p < 0.05) treatments. No adverse events were reported in either group. The study confirms the safety and efficacy of PDL in the management of the cutaneous lesions of HHT.

Actinomycotic brain abscess as the first clinical manifestation of hereditary hemorrhagic telangiectasia—case report and review of the literature

Actinomycotic brain abscess as the first clinical manifestation of hereditary hemorrhagic telangiectasia—case report and review of the literature

Raloxifene and Bevacizumab for severe complications of hereditary haemorrhagic telangiectasia in a haemodialysis patient.

Hereditary haemorrhagic telangiectasia (HHT), or Osler–Weber–Rendu syndrome, is inherited in an autosomal-dominant fashion. There are two different forms of HHT: HHT type 1, caused by mutations in the endoglin gene, located in chromosome 9 (which encodes endoglin), and HHT type 2, caused by mutations in the gene encoding activin A receptor type II-like 1 (ALK1) on chromosome 12. Mucocutaneous telangiectasias, arteriovenous malformations, epistaxis, gastrointestinal bleeding and iron-deficiency anaemia are the commonest clinical manifestations of HHT [1]. Hepatic involvement, characterized by different arteriovenous malformations within the liver parenchyma, occurs in up to 74% of patients with HHT [2]. As far as we know, no information has been published on therapeutic alternatives for haemodialysis patients suffering from severe complications of HHT. We report on a 59-year-old woman with chronic renal failure secondary to bilateral renal hypoplasia and undergoing haemodialysis, who received the diagnosis of HHT. She had presented relapsing epistaxis during the last year, with severe anaemia and hypotension. Due to the need for weekly transfusions and the poor tolerance to haemodialysis sessions, we consider treatment with raloxifene (60 mg/day), a selective estradiol receptor modulator. Raloxifene increases the expression of endoglin and ALK1, whose synthesis is defective in HHT patients, at the surface of endothelial cells [3]. A remarkable improvement of HHT symptoms along with a significant decrease in the number and severity of epistaxis was observed after raloxifene treatment. However, 6 months after the onset of raloxifene treatment, the patient presented with signs and symptoms of high-output cardiac failure, with severe ascites and a left pleural effusion. Increase of haemodialysis ultrafiltration along with large-volume paracentesis were started, but the patient showed a poor tolerance to these measures, owing to the presence of anaemia, hypotension and chronic liver disease. Serum biochemistry demonstrated a progressive cholestasis. A computed tomography (CT) scan showed liver cirrhosis with splenomegaly and massive arteriovenous malformations (Figure 1). Prompted by the progressive clinical deterioration of the patient, we decided to start treatment with bevacizumab, a humanized recombinant monoclonal antibody against the vascular endothelial growth factor (VEFG). The VEGF is a key regulator of angiogenesis and is upregulated in a variety of diseases. On the other hand, endoglin and ALK1 are involved in the transforming growth factor-β signalling pathway, which is a potent stimulator of VEFG production. Bevacizumab has been shown to be effective in diseases of abnormal angiogenesis, improving survival and symptomatology [4, 5]. Bevacizumab has been also used for the treatment of liver complications of HHT, inducing a clear improvement [6]. After obtaining the patient's informed consent, six courses of bevacizumab (5 mg/kg) were administered during a 3-month period and raloxifene was maintained without changes. A further reduction in the frequency of epistaxis was observed besides a remarkable improvement of ascites and liver enzymes. As shown in Figure 1, serial CT scans demonstrated a clear diminution of hepatic vascularity and a smooth contour of the liver. Fig. 1. CT scan of the liver with intravenous contrast before and 6 months after bevacizumab treatment, showing a dramatic reduction of vascularity and improvement of liver surface. Many different therapies have been proposed for epistaxis and hepatic involvement in HHT, but none of them have shown conclusive results. Hormonal therapy with estradiol for epistaxis and gastrointestinal management of HHT has shown a variable degree of efficacy depending on the patient. According to our experience, both raloxifene and bevacizumab are very effective alternatives for the treatment of severe HHT in haemodialysis patients.

The Prevalence of Hereditary Hemorrhagic Telangiectasia in Juvenile Polyposis Syndrome

Juvenile polyposis syndrome is a dominant GI polyposis syndrome defined by ≥ 5 GI juvenile polyps or ≥ 1 juvenile polyps with a family history of juvenile polyposis. Mutations in BMPR1A or SMAD4 are found in 50% of individuals. Hereditary hemorrhagic telangiectasia is a dominant disorder characterized by epistaxis, visceral arteriovenous malformations, and telangiectasias. Hereditary hemorrhagic telangiectasia is diagnosed when ≥ 3 criteria including clinical manifestations or a family history, are present. A juvenile polyposis-hereditary hemorrhagic telangiectasia overlap syndrome has previously been reported in 22% of patients with juvenile polyposis due to a SMAD4 mutation. Our objective was to determine the prevalence and clinical manifestations of hereditary hemorrhagic telangiectasia by Curacao criteria in our juvenile polyposis SMAD4 patients. This was a cohort study of juvenile polyposis patients in our inherited colon cancer registries. Hereditary hemorrhagic telangiectasia manifestations were obtained from medical records, patient contact, and/or prospective hereditary hemorrhagic telangiectasia screening. The Curacao criteria was used for diagnosis of hereditary hemorrhagic telangiectasia (≥ 3 criteria diagnostic; 2 criteria suspect of). Prevalence and clinical manifestations of hereditary hemorrhagic telangiectasia in juvenile polyposis SMAD4 patients. Forty-one juvenile polyposis families were identified. Genetic testing was available for individuals within 18 families. SMAD4 mutations were found in 21 relatives in 9 families. Eighty-one percent of SMAD4 patients had hereditary hemorrhagic telangiectasia and 14% were suspected of having hereditary hemorrhagic telangiectasia. Epistaxis and asthma are the most common symptoms in our overlap patients. Symptomatic and subclinical arteriovenous malformations were noted near universally. There was a single, tertiary referral center. Nearly all juvenile polyposis SMAD4 patients have the overlap syndrome. The clinical implications and need for hereditary hemorrhagic telangiectasia screening are important factors for genetic testing in juvenile polyposis. Health care providers must be cognizant of the juvenile polyposis-hereditary hemorrhagic telangiectasia overlap syndrome and the implications for management of these patients.

Spinal arteriovenous fistulas in children with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant angiodysplasia with high penetrance and variable expression. The manifestations of HHT are often age related, and spinal arteriovenous fistula (AVF) may be the initial presentation of HHT in young children. Because spinal AVFs are rarely reported, however, screening is not incorporated into current clinical recommendations for the treatment of patients with HHT. The authors describe 2 cases of children younger than 2 years of age with acute neurological deterioration in the context of a spinal AVF and in whom HHT was subsequently diagnosed. One patient presented with intraventricular and subarachnoid hemorrhage and the other with acute thrombosis of an intramedullary varix. These cases highlight the potential for significant neurological morbidity from a symptomatic AVF in very young children with HHT. Given the lack of data regarding the true incidence and natural history of these lesions, these cases raise the question of whether spinal cord imaging should be incorporated into screening recommendations for patients with HHT.

Hereditary hemorrhagic telangiectasia–related epistaxis: innovations in understanding and management

Epistaxis is the most common manifestation of hereditary hemorrhagic telangiectasia (HHT), affecting approximately 90% of patients at some point during their lifetime. Bleeding is chronic and varies from mild, self-limited episodes to severe, transfusion-dependent or life-threatening epistaxis. Treatment options vary from conservative, nonsurgical management to more aggressive surgical approaches. A number of treatment options have been introduced in recent years. There is little consensus in the literature regarding treatment algorithms. The objective of this investigation was to provide a contemporary review of HHT-related epistaxis, including pathophysiology, disease manifestations, and state-of-the-art treatment modalities. A systematic review of the literature for HHT-related epistaxis was performed using the search terms "hereditary hemorrhagic telangiectasia" and "epistaxis." Additional literature search regarding current recommendations for HHT evaluation and recent developments in genetic mechanisms, pathophysiology, and treatment of HHT was also performed. A total of 308 articles were identified and reviewed for appropriateness of inclusion whereas 64 articles met inclusion criteria. Treatment options range from topical and hormonal therapy to more aggressive surgical modalities. Most treatment descriptions are case series, with few randomized controlled trials. A number of new and novel therapies have been introduced in recent years. HHT is a heterogeneous disease requiring multidisciplinary evaluation and treatment. Therapeutic options for HHT-related epistaxis vary from conservative, nonsurgical measures to more aggressive surgical treatments. A graduated treatment plan is recommended. Patients present with a wide degree in variation of severity of epistaxis, and treatment is best tailored to the individual patient.

Hepatic sonography in patients with hereditary hemorrhagic telangiectasia hospitalized for epistaxis

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by the presence of telangiectasias and arteriovenous malformations in various organs and organ systems, including the liver. The most frequent clinical manifestation of HHT is epistaxis.In 2010 (January–December inclusive) 51 patients with HHT were admitted to the ENT ward of our hospital for epistaxis, and in accordance with routine protocols, all 51 underwent abdominal ultrasonography in our department to detect hepatovascular lesions. They included 27 males (53%) and 24 (47%) females ranging in age from 11 to 86 years (mean 48.5 years). The sample was selected in an arbitrary manner to take maximum advantage of the hospital stay and monitor patients from regions other than our own.Retrospective analysis of the findings from these sonographic examinations revealed hepatic HHT in 27 (53%) of the 51 patients. Nineteen (70%) of these (age range 40–86 years, mean 63) had vascular malformations of various dimensions but no portal hypertension; the other eight (30%) (age range 39–81 years, mean 60) had vascular malformations plus portal hypertension.Our retrospective analysis indicates that a significant number of patients can have unrecognized hepatic involvement; that the appearance of hepatic lesions can be fairly unpredictable, even when the HHT has been diagnosed for years and the patients are already symptomatic; and that the hepatic lesions are frequently progressive. Therefore, regular sonographic follow-up is advisable for patients with HHT.The limitations of this study are related to the small number of patients examined and to the fact that all of them were symptomatic. Further study is therefore needed (especially in asymptomatic patients) to define the indications for hepatic sonography and the optimum examination schedule.

Hereditary hemorrhagic telangiectasia

Hereditary Hemorrhagic Telangiectasia (HHT) or Osler-Weber-Rendu disease is an autosomal dominant genetic disorder. HHT frequently presents with gastrointestinal bleeding with diagnostic and therapeutic challenge. Hepatic involvement in this disease is increasingly recognized and poses another therapeutic challenge. With advances in genetic screening and diagnostic procedures, and the increasing awareness of the condition by physicians and patients, this disease is now diagnosed more often. This case report reviews the available literature on various manifestations of HHT, and the various diagnostic and therapeutic modalities available for its management.

Oxidative Stress Contributes to Endothelial Dysfunction in Mouse Models of Hereditary Hemorrhagic Telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is a vascular dysplasia caused by mutations in endoglin (ENG; HHT1) or activin receptor-like kinase (ALK1; HHT2) genes, coding for transforming growth factor-β (TGF-β) superfamily receptors. We demonstrated previously that endoglin and ALK1 interact with endothelial NO synthase (eNOS) and affect its activation. Endothelial cells deficient in endoglin or ALK1 proteins show eNOS uncoupling, reduced NO, and increased reactive oxygen species (ROS) production. In this study, we measured NO and H2O2 levels in several organs of adult Eng and Alk1 heterozygous mice, to ascertain whether decreased NO and increased ROS production is a generalized manifestation of HHT. A significant reduction in NO and increase in ROS production were found in several organs, known to be affected in patients. ROS overproduction in mutant mice was attributed to eNOS, as it was L-NAME inhibitable. Mitochondrial ROS contribution, blocked by antimycin, was highest in liver while NADPH oxidase, inhibited by apocynin, was a major source of ROS in the other tissues. However, there was no difference in antimycin- and apocynin-inhibitable ROS production between mutant and control mice. Our results indicate that eNOS-derived ROS contributes to endothelial dysfunction and likely predisposes to disease manifestations in several organs of HHT patients.

Are patients with severe epistaxis caused by hereditary hemorrhagic telangiectasia satisfied with nostril closure surgery?

Recurrent epistaxis as a manifestation of hereditary hemorrhagic telangiectasia (HHT) is usually difficult to control. Although no treatment is regarded to be completely efficacious, nostril closure is considered a modality of choice for the most severe cases. The cessation of airflow resulting from this procedure can stop bleeding by minimizing risk factors. However, loss of nasal functions is a disadvantage of nostril closure. We conducted a questionnaire survey of patients who underwent nostril closure surgery, regarding the effects and disadvantages of the operation. Seven patients were asked questions on issues including frequency and severity of epistaxis pre- and post-operatively, satisfaction of treatment, and impairment in daily living activities. Most patients reported complete cessation of bleeding. Some still had bleeding, but the frequency and severity were far lower. No transfusions were required in any of the cases. Patients reported some disadvantages, for example, respiratory, olfactory, and phonatory issues. Six out of seven patients were very satisfied with the outcome of surgery. Nostril closure surgery can remarkably reduce frequency and volume of epistaxis. Our survey indicated that satisfactory results were achieved. However, difficulties caused by complete nasal obstruction varied. Thus, individualized coping strategies are required.

Mosaic ACVRL1 and ENG mutations in hereditary haemorrhagic telangiectasia patients

Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant disorder caused by mutations in the ACVRL1, ENG, and SMAD4 genes. HHT is commonly characterised by small arteriovenous malformations (AVMs) known as...

A Review on Clinical Management and Pharmacological Therapy on Hereditary Haemorrhagic Telangiectasia (HHT)

Hereditary Haemorrhagic Telangiectasia (HHT) or Rendu-Osler-Weber syndrome, is an autosomal dominant rare disease characterized by localized angiodysplasia. This is manifested as epistaxis, mucocutaneous and gastrointestinal telangiectases, and arteriovenous malformations in the pulmonary, cerebral or hepatic circulation. The prevalence is between 1 in 5,000 to 8,000, although it is higher in some regions. The most frequent clinical manifestation of HHT is epistaxis, normally from light to moderate from the 4(th) decade of life. However, many patients show severe epistaxis which may interfere with their quality of life. The epistaxis is due to telangiectasia on the nasal mucosa. These are focally dilated postcapilar venules, which in advanced phases show many layers of smooth muscle cells without elastic fibers, and very frequently directly connect with dilated arterioles. As a consequence of these vascular alterations, telangiectases are very sensitive to slight trauma and even to the friction with the air when breathing, which gives rise to nose bleeds. Unfortunately, there is no optimal pharmacological treatment for the epistaxis in HHT. The use of antifibrinolytic agents for the treatment of HHT has been studied recently by our group as an effective relief for nasal and gastric haemorrhages. This work represents a systematic review and the beginning of a systematic laboratory work we are now conducting in our lab to screen for "orphan drugs" as therapeutic agents in HHT. In this context, the use of hormones, immunosuppresants and anti-angiogenic agents are under preclinical study in our laboratory.

Experience of the Irish National Centre for hereditary haemorrhagic telangiectasia 2003–2008

Hereditary haemorrhagic telangiectasia (HHT) is a group of autosomal dominant disorders of vascular structure. The Irish National Centre for HHT at the Mercy University Hospital, Cork, Ireland was founded in 2003. From 2003 to 2008, screening of 164 patients with contrast echocardiography, thoracic computerised tomography (CT) and cerebral magnetic resonance imaging (MRI) has identified 88 patients with definite HHT, 72 (82%) of whom had epistaxis, 70 (80%) had telangiectasia and 81 (92%) had a first-degree relative with HHT. We sought to describe the manifestations of HHT in an Irish population and to determine differences between internationally reported data. The HHT patient database was analysed to describe demographics, clinical manifestations and interventional procedures performed in all referred patients. Contrast echocardiography and/or CT were performed in 86 patients with definite HHT, identifying 27 patients (31%) with pulmonary arteriovenous malformations (pAVMs). Nineteen patients with single or multiple pAVMs had 28 embolisation procedures performed, with 1-6 pAVMs embolised per procedure. Cerebral MRI was performed in 78 (89%) patients and 2 (2.3%) had cerebral arteriovenous malformations (cAVMs). HHT prevalence is thought to be 1 in 2500-8000, suggesting that there are many undiagnosed cases in Irish patients. Internationally published data suggest a prevalence of 15-35% for pAVMs and 10-23% for cAVMs in patients with HHT. While the prevalence of pAVMs in our group is consistent with these data, the prevalence of cAVMs is considerably lower, suggesting that Irish patients with HHT may differ genotypically and phenotypically from those in other countries.

Hemothorax Due to Rupture of Pulmonary Arteriovenous Malformation: An Interventional Emergency

Spontaneous hemothorax as a result of a ruptured pulmonary arteriovenous malformation (PAVM) is a life-threatening event and requires immediate interventional therapy. We present two patients who survived following emergent embolization. Definitive thoracentesis was delayed until embolization was performed. The tamponade provided by the hemothorax may have prevented exsanguination, suggesting to us that drainage of blood from the pleural space should be delayed until the PAVM has been treated. Hemorrhage from a PAVM may be the first manifestation of hereditary hemorrhagic telangiectasia. Genetic testing and screening for other family members should be considered.

Overlapping spectra of SMAD4 mutations in juvenile polyposis (JP) and JP–HHT syndrome

Juvenile polyposis (JP) and hereditary hemorrhagic telangiectasia (HHT) are clinically distinct diseases caused by mutations in SMAD4 and BMPR1A (for JP) and endoglin and ALK1 (for HHT). Recently, a combined syndrome of JP-HHT was described that is also caused by mutations in SMAD4. Although both JP and JP-HHT are caused by SMAD4 mutations, a possible genotype:phenotype correlation was noted as all of the SMAD4 mutations in the JP-HHT patients were clustered in the COOH-terminal MH2 domain of the protein. If valid, this correlation would provide a molecular explanation for the phenotypic differences, as well as a pre-symptomatic diagnostic test to distinguish patients at risk for the overlapping but different clinical features of the disorders. In this study, we collected 19 new JP-HHT patients from which we identified 15 additional SMAD4 mutations. We also reviewed the literature for other reports of JP patients with HHT symptoms with confirmed SMAD4 mutations. Our combined results show that although the SMAD4 mutations in JP-HHT patients do show a tendency to cluster in the MH2 domain, mutations in other parts of the gene also cause the combined syndrome. Thus, any mutation in SMAD4 can cause JP-HHT. Any JP patient with a SMAD4 mutation is, therefore, at risk for the visceral manifestations of HHT and any HHT patient with SMAD4 mutation is at risk for early onset gastrointestinal cancer. In conclusion, a patient who tests positive for any SMAD4 mutation must be considered at risk for the combined syndrome of JP-HHT and monitored accordingly.

Clinical Outcomes of Pulmonary Arterial Hypertension in Patients Carrying an ACVRL1 (ALK1) Mutation

Activin A receptor type II-like kinase-1 (ACVRL1, also known as ALK1) mutation is a cause of hereditary hemorrhagic telangiectasia (HHT) and/or heritable pulmonary arterial hypertension (PAH). To describe the characteristics of patients with PAH carrying an ACVRL1 mutation. We reviewed clinical, functional, and hemodynamic characteristics of 32 patients with PAH carrying an ACVRL1 mutation, corresponding to 9 patients from the French PAH Network and 23 from literature analysis. These cases were compared with 370 patients from the French PAH Network (93 with a bone morphogenetic protein receptor type 2 [BMPR2] mutation and 277 considered as idiopathic cases without identified mutation). Distribution of mutations in the ACVRL1 gene in patients with PAH was compared with the HHT Mutation Database. At diagnosis, ACVRL1 mutation carriers were significantly younger (21.8 +/- 16.7 yr) than BMPR2 mutation carriers and noncarriers (35.7 +/- 14.9 and 47.6 +/- 16.3 yr, respectively; P < 0.0001). In seven of the nine patients from the French PAH Network, PAH diagnosis preceded manifestations of HHT. ACVRL1 mutation carriers had better hemodynamic status at diagnosis, but none responded to acute vasodilator challenge and they had shorter survival when compared with other patients with PAH despite similar use of specific therapies. ACVRL1 mutations in exon 10 were more frequently observed in patients with PAH, as compared with what was observed in the HHT Mutation Database (33.3 vs. 5%; P < 0.0001). ACVRL1 mutation carriers were characterized by a younger age at PAH diagnosis. Despite less severe initial hemodynamics and similar management, these patients had worse prognosis compared with other patients with PAH, suggesting more rapid disease progression.

Index of Suspicion

Index of Suspicion

Worsening of Nose Bleeding Heralds High Cardiac Output State in Hereditary Hemorrhagic Telangiectasia

Background Hereditary hemorrhagic telangiectasia is characterized by arteriovenous malformations or telangiectasias in multiple organs. Nose bleeding is the most common manifestation of hereditary hemorrhagic telangiectasia and can be debilitating. Cardiac involvement in the form of high-output cardiac failure is a poorly studied complication of hereditary hemorrhagic telangiectasia. The objective of this study is to describe the natural history of high-output cardiac failure in hereditary hemorrhagic telangiectasia and define the relation between bleeding complications and high-output cardiac failure. Methods In this case-control study at the Washington University hereditary hemorrhagic telangiectasia center, all patients evaluated for hereditary hemorrhagic telangiectasia and found to have high cardiac output between 1999 and 2006 were enrolled as cases (n = 17) and compared with 17 hereditary hemorrhagic telangiectasia controls without high-output cardiac failure. Results During lifetime, cases needed more transfusions, emergency department visits, and hospital admission for nose bleeding. Cases experienced significant worsening of nose bleeding immediately before heart failure diagnosis. During the 2 years before study-related evaluation, 16 (94%) cases needed transfusions every month as compared with 2 (12%) controls ( P <.001). The number of transfusions required during these 2 years also was higher in cases (median 3, range 0-12) as compared with controls (median 0, range 0-1.5, P <.001). Conclusions Hereditary hemorrhagic telangiectasia patients with high-output cardiac failure have significantly greater nose bleeding as compared with patients without high-output cardiac failure. In addition, nose bleeding worsens around the time of development of high-output cardiac failure. Early recognition of the relationship between severe nose bleeding and high-output cardiac failure can lead to earlier diagnosis and provide an opportunity for earlier institution of therapy for high-output cardiac failure.

HYPERMANGANESEMIA, HEREDITARY HEMORRHAGIC TELANGIECTASIA, BRAIN ABSCESS: THE HEPATIC CONNECTION

Hypermanganesemia related pallidal T1-hyperintensity is a rare manifestation of hereditary hemorrhagic telangiectasia (HHT).1 Levodopa-unresponsive parkinsonism has been described in HHT.1 We report a patient who presented with brain abscess–related seizures and was diagnosed with the HHT-juvenile polyposis overlap syndrome with hypermanganesemia. This report highlights the multifactorial pathogenesis of hypermanganesemia in HHT. ### Case report. A 35-year-old man was referred for embolization of pulmonary arteriovenous malformations (AVMs) which were detected on a chest CT done to investigate the cause of a left frontoparietal abscess. A month earlier he presented with recurrent generalized tonic-clonic seizures. Brain MRI showed a ring-enhancing left frontoparietal mass with edema (figure, A and B). Biopsy revealed purulent fluid which grew Streptococcus viridans and anaerobic Gram-negative rods. He had a past history of epistaxis, left eye hemorrhage, gum bleeds, iron deficiency anemia, and lower gastrointestinal bleeding. Endoscopy revealed multiple telangiectasia involving the gastroduodenal mucosa and colonic polyps. A colectomy revealed multiple tubulovillous adenomas. His family history was positive for epistaxis in his mother. His examination was unremarkable except for oral telangiectasia. Hepatic function assessed by liver enzymes was normal. Figure Coronal T1 with contrast (A), sagittal T1 with contrast (B), and axial T1 FLAIR (C, D) MRI sequences …