Screening for children from families with Rendu-Osler-Weber disease: from geneticist to clinician

Oral manifestations and dental considerations of patients with hereditary hemorrhagic telangiectasia: a scoping review

OBJECTIVE

We examined the range, nature, and extent of research conducted regarding the oral and dental implications of hereditary hemorrhagic telangiectasia (HHT) to identify gaps in the research and knowledge of the field.

STUDY DESIGN

We performed a scoping review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews and 2017 Guidance for the Conduct of Joanna Briggs Institute Scoping Reviews. We searched the MEDLINE and Web of Science databases for all full-text articles published in English from December 1946 to October 2022.

RESULTS

We identified 103 articles describing oral and dental considerations of patients with HHT, primarily case reports. Most reported oral telangiectasias of the tongue, lips, and palate. Many reported management of bleeding and the use or recommendation of prophylactic antibiotics before dental procedures.

CONCLUSIONS

Oral telangiectasias are commonly found in patients with hereditary hemorrhagic telangiectasia, and dental professionals may be the first to diagnose it in their patients. Early detection and diagnosis are important to prevent potentially fatal outcomes, and prophylactic antibiotics before procedures may be warranted.

Longitudinal Assessment of Curaçao Criteria in Children with Hereditary Hemorrhagic Telangiectasia

OBJECTIVE

To assess the utility of the Curaçao criteria by age over time in children with hereditary hemorrhagic telangiectasia (HHT).

STUDY DESIGN

This was a single-center, retrospective analysis of patients attending the HHT clinic at the Hospital for Sick Children (Toronto, Canada) between 2000 and 2019. The evaluation of the Curaçao criteria was completed during initial and follow-up visits. Screening for pulmonary and brain arteriovenous malformations was completed at 5 yearly intervals.

RESULTS

A total of 116 patients with genetic confirmation of HHT were included in the analysis. At initial screening at a median (IQR) age of 8.4 (2.8, 12.9) years, 41% met criteria for a definite clinical diagnosis (≥3 criteria). In children <6 years at presentation, only 23% fulfilled at least 3 criteria initially. In longitudinal follow-up, 63% reached a definite clinical diagnosis, with a median (IQR) follow-up duration of 5.2 (3.2, 7.9) years (P = .005). Specifically, more patients met the epistaxis and telangiectasia criteria at last visit compared with initial (79% vs 60%; P = .006; 47% vs 30%; P = .02) but not for the arteriovenous malformation criterion (59% vs 57%; P = .65).

CONCLUSIONS

In the pediatric population, most patients do not meet definite clinical criteria of HHT at initial presentation. Although the number of diagnostic criteria met increased over time, mainly due to new onset of epistaxis and telangiectasia, accuracy remained low during follow-up visits. Relying solely on clinical criteria may lead to underdiagnosis of HHT in children.

Hereditary Hemorrhagic Telangiectasia in Pediatric Age: Focus on Genetics and Diagnosis

Hereditary Hemorrhagic Telangiectasia (HHT) or Rendu-Osler-Weber Syndrome (ROW) is an autosomal dominant vascular disease, with an estimated prevalence of 1:5000. Genes associated with HHT are ACVRL1, ENG, SMAD4, and GDF2, all encoding for proteins involved in the TGFβ/BMPs signaling pathway. The clinical diagnosis of HHT is made according to the "Curaçao Criteria," based on the main features of the disease: recurrent and spontaneous epistaxis, muco-cutaneous telangiectases, arteriovenous malformations in the lungs, liver, and brain, and familiarity. Since the clinical signs of HHT can be misinterpreted, and the primary symptom of HHT, epistaxis, is common in the general population, the disease is underdiagnosed. Although HHT exhibits a complete penetrance after the age of 40, young subjects may also present symptoms of the disease and are at risk of severe complications. Here we review the literature reporting data from clinical, diagnostic, and molecular studies on the HHT pediatric population.

Spontaneous Hemothorax by Pulmonary Arteriovenous Malformation during Pregnancy

Background:  Pulmonary arteriovenous malformation (PAVM) is a rare vascular malformation that may cause hemothorax, especially during pregnancy. Case Description:  A 25-year-old woman presented sudden-onset left chest pain, dizziness, and dyspnea in the 27th week of gestation. Computed tomography angiography showed left pleural effusion with complete hemithorax opacification and an aneurysmal PAVM. She exhibited hemorrhagic shock and received emergency exploratory video-assisted thoracic surgery. A ruptured PAVM was identified and stopped by wedge resection in the upper lobe of the left lung. The patient's postoperative clinical course was uncomplicated. She subsequently delivered a healthy live baby vaginally at 41 weeks gestation. Conclusion:  PAVM should be considered in pregnant women with hemothorax. Emergency thoracoscopic surgery is the best treatment option.

Genetic counseling and testing for hereditary hemorrhagic telangiectasia

Genetic counseling is an important means of identifying a patient's genetic risk of hereditary hemorrhagic telangiectasia (HHT) and assisting patients in making informed decisions about their health. With an increase in understanding of the genetic mechanisms underlying HHT over the last decade, genetic counseling is increasingly being incorporated into the care of patients affected by HHT. In addition to refining the diagnosis of symptomatic patients, genetic testing can help to distinguish asymptomatic, at-risk patients from those who are unaffected by HHT. The purpose of this review article is to summarize the current knowledge regarding the role of genetic counseling and genetic testing in identifying and managing HHT in at-risk populations. This article also reviews the guidelines, outcomes, risks, and challenges of genetic counseling and testing for HHT in various patient populations, and provides an algorithm for the use of genetic counseling in symptomatic and asymptomatic patients.

Founder Effects in Hereditary Hemorrhagic Telangiectasia

A founder effect can result from the establishment of a new population by individuals from a larger population or bottleneck events. Certain alleles may be found at much higher frequencies because of genetic drift immediately after the founder event. We provide a systematic literature review of the sporadically reported founder effects in hereditary hemorrhagic telangiectasia (HHT). All publications from the ACVRL1, ENG and SMAD4 Mutation Databases and publications searched for terms “hereditary hemorrhagic telangiectasia” and “founder” in PubMed and Scopus, respectively, were extracted. Following duplicate removal, 141 publications were searched for the terms “founder” and “founding” and the etymon “ancest”. Finally, 67 publications between 1992 and 2020 were reviewed. Founder effects were graded upon shared area of ancestry/residence, shared core haplotypes, genealogy and prevalence. Twenty-six ACVRL1 and 12 ENG variants with a potential founder effect were identified. The bigger the cluster of families with a founder mutation, the more remarkable is its influence to the populational ACVRL1/ENG ratio, affecting HHT phenotype. Being aware of founder effects might simplify the diagnosis of HHT by establishing local genetic algorithms. Families sharing a common core haplotype might serve as a basis to study potential second-hits in the etiology of HHT.

Second International Guidelines for the Diagnosis and Management of Hereditary Hemorrhagic Telangiectasia

DESCRIPTION

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease with an estimated prevalence of 1 in 5000 that is characterized by the presence of vascular malformations (VMs). These result in chronic bleeding, acute hemorrhage, and complications from shunting through VMs. The goal of the Second International HHT Guidelines process was to develop evidence-based consensus guidelines for the management and prevention of HHT-related symptoms and complications.

METHODS

The guidelines were developed using the AGREE II (Appraisal of Guidelines for Research and Evaluation II) framework and GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. The guidelines expert panel included expert physicians (clinical and genetic) in HHT from 15 countries, guidelines methodologists, health care workers, health care administrators, patient advocacy representatives, and persons with HHT. During the preconference process, the expert panel generated clinically relevant questions in 6 priority topic areas. A systematic literature search was done in June 2019, and articles meeting a priori criteria were included to generate evidence tables, which were used as the basis for recommendation development. The expert panel subsequently convened during a guidelines conference to conduct a structured consensus process, during which recommendations reaching at least 80% consensus were discussed and approved.

RECOMMENDATIONS

The expert panel generated and approved 6 new recommendations for each of the following 6 priority topic areas: epistaxis, gastrointestinal bleeding, anemia and iron deficiency, liver VMs, pediatric care, and pregnancy and delivery (36 total). The recommendations highlight new evidence in existing topics from the first International HHT Guidelines and provide guidance in 3 new areas: anemia, pediatrics, and pregnancy and delivery. These recommendations should facilitate implementation of key components of HHT care into clinical practice.

Autologous correction in patient induced pluripotent stem cell-endothelial cells to identify a novel pathogenic mutation of hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia is a rare disease with autosomal dominant inheritance. More than 80% hereditary hemorrhagic telangiectasia patients carry heterozygous mutations of Endoglin or Activin receptor-like kinase-1 genes. Endoglin plays important roles in vasculogenesis and human vascular disease. In this report, we found a novel missense mutation (c.88T > C) of Endoglin gene in a hereditary hemorrhagic telangiectasia 1 patient. Induced pluripotent stem cells of the patient were generated and differentiated into endothelial cells. The hereditary hemorrhagic telangiectasia-induced pluripotent stem cells have reduced differentiation potential toward vascular endothelial cells and defective angiogenesis with impaired tube formation. Endoplasmic reticulum retention of the mutant Endoglin (Cys30Arg, C30R) causes less functional protein trafficking to cell surface, which contributes to the pathogenesis of hereditary hemorrhagic telangiectasia. Clustered Regularly Interspaced Short Palindromic Repeats/Cas9 genetic correction of the c.88T > C mutation in induced pluripotent stem cells revealed that C30R mutation of Endoglin affects bone morphogenetic protein 9 downstream signaling. By establishing a human induced pluripotent stem cell from hereditary hemorrhagic telangiectasia patient peripheral blood mononuclear cells and autologous correction on mutant hereditary hemorrhagic telangiectasia-induced pluripotent stem cells, we were able to identify a new disease-causing mutation, which facilitates us to understand the roles of Endoglin in vascular development and pathogenesis of related vascular diseases.

Point-of-care echocardiography for the evaluation of right-to-left cardiopulmonary shunts: a narrative review

Right-to-left pulmonary and cardiac shunts (RLS) are important causes of refractory hypoxia in the critically-ill perioperative patient. Using a point-of-care ultrasound (POCUS) agitated saline bubble study for an early diagnosis allows patients with clinically significant RLSs to receive expedited therapy. This narrative review discusses the principles of agitated saline ultrasonography as well as the role of POCUS in detecting the most common RLS types seen in the intensive care unit, including patent foramen ovale, atrial septal defects, and pulmonary arterio-venous malformations. An illustrated discussion of the procedure, as well as shunt-enhancing maneuvers (Valsalva or lung recruitment maneuver with subsequent rapid release) is provided. With the wide dissemination of bedside ultrasound within the perioperative and critical care arena, POCUS practitioners should be knowledgeable of the potential pitfalls leading to both false-positive and false-negative studies. False-positive studies may be due to congenital abnormalities, mischaracterization of intrapulmonary shunts as intracardiac shunts (and vice versa), or evidence of the Valsalva effect. False negatives are typically due to respiratory-phasic variation, performing an inadequate shunt-enhancing maneuver, inadequate injection of agitated saline, or pathophysiologic states of elevated left atrial pressure. Finally, alternative POCUS methods for determining presence of an RLS in patients with poor echocardiographic windows are discussed, with a focus on pulsed-wave Doppler interrogation of arterial signals.

Hereditary hemorrhagic telangiectasia: how to efficiently detect hepatic abnormalities using ultrasonography

INTRODUCTION

Hereditary hemorrhagic telangiectasia (HHT) is a multiorgan genetic angiodysplastic affection characterized by visceral vascular malformations. It affects mainly the brains, lungs, gastrointestinal tract, and nasal mucosa. Unlike those organs, hepatic involvement, although very frequently occurring, is insufficiently recognized, mainly because of the complex vascular structure of this organ. Thus, treating HHT patients requires a solid understanding of these hepatic anomalies. It is especially important for any general clinicians to be able to recognize clinical findings in HHT, which leads to a high suspicion of HHT and have an index of suspicion for liver abnormalities of HHT. For this purpose, keen awareness of clinical as well as hepatic sonographic (US) findings is paramount.

AIM

The aim of this review is to summarize previously reported findings on the hepatic US through a thorough analysis of related articles, and to (a) determine the role of US in the diagnosis of hepatic involvement in HHT patients and (b) propose the most simple and easy way to detect HHT-related abnormalities during routine US examinations.

CONCLUSION

Hepatic US serves to diagnose the detailed complex hepatic changes typical of HHT, and contributes to increased diagnostic confidence of hepatic changes in HHT patients, with the most simple way not to overlook HHT-related abnormalities being to find hepatic artery dilatation.

Hypoxemia without Respiratory Distress: Hereditary Hemorrhagic Telangiectasia in a Child

Hereditary hemorrhagic telangiectasia (HHT) is an underrecognized genetic disorder of vascular development in pediatric patients. Its presentation can range from mild cutaneous findings to life-threatening hemorrhage from arteriovenous malformations. Clinical diagnosis can be challenging in the pediatric population as disease manifestations evolve over time and may be difficult to identify in younger patients. This case highlights how nonspecific symptoms and signs in the preanesthesia period can be misleading, potentially placing a patient with unrecognized HHT at risk for significant morbidity and mortality.

Pulmonary Arteriovenous Malformations (PAVMs) and Pregnancy: A Rare Case of Hemothorax and Review of the Literature

Pulmonary arteriovenous malformations (PAVMs) are anatomical abnormalities consisting in a direct connection between pulmonary arteries and veins. Most of PAVMs are related to Hereditary Hemorrhagic Teleangiectasia, whereas only 10 to 20% are isolated sporadic cases. PAVMs tend to increase in size naturally; however, several factors can influence their growth such as pulmonary arterial hypertension, puberty, and pregnancy. Clinical manifestations are related to the right-to-left shunting and include dyspnoea, hypoxia, and pulmonary hypertension. The presence of PAVMs during pregnancy is associated with an increased risk of complications such as their rupture, haemothorax, and hypovolemic shock. The treatment reserved to PAVMs was the surgical resection of the lung lobe involving the malformation. Due to the worldwide acceptance of endovascular technique, the transcatheter embolization (TCE) is today considered as the mainstay of treatment. Recent studies reported the safeness of the TCE during pregnancy if performed by an experienced radiologist, at second or third trimesters when radiation exposure is believed to have minimal effect on the foetus. However, although the TCE during pregnancy represents an option, the treatment prior to pregnancy has to be considered the auspicial solution. Our study reports the case of a dyspnoeic pregnant woman with unknown pAVM causing hemothorax and simultaneously treated for pAVM reparation, left lower lobe resection, and hysterectomy. Postoperative treatment of embolization was performed to definitively close the pAVM.

Growth of Pulmonary Arteriovenous Malformations in Pediatric Patients with Hereditary Hemorrhagic Telangiectasia

The evolution of pulmonary arteriovenous malformations (PAVMs) over time in children with hereditary hemorrhagic telangiectasia (HHT) is not well-defined. Herein we demonstrate that, although new PAVMs did not evolve in children with HHT, existing PAVMs exhibit quantitative growth over time highlighting the need for ongoing follow-up throughout childhood.

Pulmonary arteriovenous malformations in children with hereditary hemorrhagic telangiectasia: a longitudinal study

Pulmonary arteriovenous malformations (PAVMs) often occur in children with hereditary hemorrhagic telangiectasia (HHT). A 14-year longitudinal study of PAVMs in children with HHT was undertaken to assess the prevalence, the clinical impact, and progression of these malformations. This was a retrospective, single-center study from May 2002 to December 2016 of 129 children with HHT diagnosed using Curacao criteria and/or confirmed by genetic testing. Transthoracic contrast echocardiography (TTCE) was the primary screening modality in all patients and PAVMs were diagnosed based on Barzilai criteria. Moderately positive TTCE (Barzilai criteria ≥ 2) was confirmed with subsequent contrast chest CT. New PAVMs were diagnosed with a positive TTCE after an initial negative TTCE. Embolization of PAVMs were performed according to HHT consensus guidelines. Of 129 children with HHT, 76 (59%) were found to have PAVMs. Sixty-seven (88%) were positive for PAVMs on initial screening. Of 63 children without PAVMs on initial screening, 31 were followed for >1 year. Nine of the 31 (29%) developed new PAVMs after initial negative study. Thirty-eight (50%) of the total 76 children with PAVMs had or developed lesions large enough to be treated with embolization. Nine patients with PAVMs initially too small to be treated with embolization, developed progression of disease and ultimately were treated with embolization over time. The majority, 60% (23/38), of the children with large PAVMs had no related clinical symptoms. After embolization, 21% (8/38), of patients underwent repeat interventions. Genetic diagnosis, age, and gender were not associated with risk of having PAVM nor with need for repeat interventions. Nearly 60% of children with HHT develop PAVMs. The risk for new PAVMs to develop, small PAVMs to become large, and previously embolized PAVMs to require further intervention remains throughout childhood. Thus, children with HHT require continued follow-up until adulthood.

Emergency video-assisted thoracic surgery for ruptured pulmonary arteriovenous malformation-related hemothorax in a pregnant woman: a case report

Background

Pulmonary arteriovenous malformations are rare vascular abnormalities that permit direct communication between the pulmonary artery and vein. During pregnancy, pulmonary arteriovenous malformation carries an increased risk of enlargement and rupture, which could lead to life-threatening hemothorax. This is the first case reporting successful thoracoscopic surgery for a pregnant woman with pulmonary arteriovenous malformation rupture-related hemothorax.

Case presentation

We present a case of a 32-year-old pregnant Asian woman (31 weeks’ gestation) whose pulmonary arteriovenous malformation ruptured, leading to right-sided spontaneous tension hemothorax. First, an emergency cesarean section for hypovolemic shock-related fetal distress was performed to save the baby. Immediately afterwards, video-assisted thoracic surgery with the single-incision approach allowed us to successfully obtain hemostasis and eradication of abnormal vasculature by conducting wedge resection of the pulmonary arteriovenous malformation.

Conclusions

Emergency thoracoscopic surgery for a pregnant woman with pulmonary arteriovenous malformation rupture-related hemothorax is safe and feasible. In contrast to transcatheter arterial embolization, video-assisted thoracic surgery could simultaneously achieve hemostasis for prevention of mortality, eradication of abnormal vasculature, and removal of massive thrombi.

Imaging findings in systemic childhood diseases presenting with dermatologic manifestations

PURPOSE

Many childhood diseases often present with skin abnormalities with which radiologists are largely unfamiliar. Knowledge of associated dermatologic manifestations may aid the radiologist in confirming the diagnosis and recommending targeted imaging of affected organs.

METHODS

We review the imaging findings in childhood diseases associated with dermatologic manifestations.

FINDINGS

Diseases include dermatologic findings which herald underlying malignancy (Neuroblastoma, leukemia/lymphoma, Langerhans cell histiocytosis),are associated with risk of malignancy (Epidermolysis Bullosa, basal cell nevus syndrome, Cowden's syndrome, Tuberous Sclerosis),or indicate a systemic inflammatory/immune disorder (Kawasaki's disease, Henoch Schonlein Purpura, systemic lupus erythematosus, scleroderma, sarcoidosis, dermatomyositis and immune thrombocytopenic purpura).

CONCLUSION

Familiarity with pertinent findings in childhood diseases presenting with dermatologic manifestations in childhood diseases aids the radiologist in confirming the diagnosis and guiding imaging workup.

[Interstitial processes of the lungs in childhood]

Interstitial processes in the lungs of children can be due to several underlying diseases. Knowledge of the child's age is important as genetic aberrations play a major role in diseases in the first 2 years, whereas immunological diseases are more common starting in kindergarden age. In general lung diseases are rare in children, which makes the diagnostics difficult and results in a delayed diagnosis. In addition, pediatric pulmonologists are often very reluctant to perform lung biopsies due to a lack of a specialized pathologist. In order to make a contribution to the diagnostics of pediatric pulmonary diseases, pathologists should be specialized in pulmonary pathology, have a good knowledge of genetic methods and fetal lung development, which includes the genetic factors involved in lung growth and differentiation. A close cooperation with the pediatric pulmonologist is necessary and each patient should be discussed jointly on an interstitial lung disease board to promote the quality of diagnostics. The pathologist should be aware that the developing lungs of children are not just a smaller form of adult lungs and often react very differently. In this article, we mainly focus on diffuse infiltration patterns, such as ground glass and reticulonodular infiltrations as described in high-resolution computed tomography (HRCT). Localized interstitial processes, which can sometimes be tumor-like and malformations are not dealt with; however, vascular malformations are included as these often manifest as diffuse interstitial infiltrations and must therefore be taken into consideration for the differential diagnostics.

Hereditary Hemorrhagic Telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an underrecognized and underdiagnosed autosomal-dominant angiodysplasia that has an estimated prevalence of 1 in 5000 individuals, with variable clinical presentations even within family members with identical mutations. The most common manifestations are telangiectasias of the skin and nasal mucosa. However, HHT can often be complicated by the presence of arteriovenous malformations and telangiectasias in the lungs, brain, gastrointestinal tract, and liver that are often silent and can lead to life-threatening complications of stroke and hemorrhage. This article reviews HHT for the pulmonologist, who is not uncommonly the first practitioner to encounter these patients.

De novo arteriovenous malformation in a patient with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant systemic disorder characterized by the enlargement of capillaries, recurrent nosebleeds, and multiple arteriovenous malformations (AVMs). Although cerebral AVMs are traditionally considered to be congenital lesions, some reports have described de novo AVMs, which suggests that the authors believed them to be dynamic conditions. In this article, the authors describe the case of a 5-year-old boy with HHT in whom a de novo cerebral AVM was detected after a negative MRI result at 5 months. To the authors' knowledge, this is the first report of a de novo AVM in a patient with HHT. In patients with a family history of HHT, de novo AVMs are possible, even when no lesions are detected at the first screening. Therefore, regular screenings need to be performed, and the family should be informed that AVMs could still develop despite normal MRI results.

Pulmonary arterovenous malformation causing hemothorax in a pregnant woman without Osler-Weber-Rendu syndrome

Pulmonary arteriovenous malformations (PAVMs), although most commonly congenital, are usually detected later in life. Case report: We present a case of a 19-year-old woman with no previous history of AVM or telangiectasia, who presented dyspnea and hypoxia by massive left hemothorax in the 34th week of gestation. After emergent cesarean delivery, a chest computed tomography (CT) with i.v. contrast showed a likely 3 cm area of active contrast in left lower lung. Chest tube placement revealed about 2 liters of blood. The patient was subsequently found to have pulmonary AVM. A successful embolisation of AVM followed by lung atipic resection involving AVM and decortication for lung re-expansion were the treatments provided. Conclusions: Women with known pulmonary AVM should be maximally treated prior to becoming pregnant, and the physician should be alert to complications of pulmonary AVM during pregnancy.

Brain arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia: clinical presentation and anatomical distribution

BACKGROUND

Hereditary hemorrhagic telangiectasia is an autosomal dominant genetic disease with a wide array of vascular malformations involving multiple organs. Brain arteriovenous malformations can lead to intracranial hemorrhage and are often diagnosed only after patients become symptomatic. Early diagnosis and interventional treatment may prevent neurologic sequelae or death. Because of the rarity of defined cases, the spectrum of presentations in children with brain arteriovenous malformations and hereditary hemorrhagic telangiectasia has not been explored in detail. Here, we report our experience in children with hereditary hemorrhagic telangiectasia and brain arteriovenous malformations regarding both disease manifestations at presentation and the spectrum of brain arteriovenous malformation manifestations.

METHODS

A retrospective review of demographics, clinical manifestations, and brain magnetic resonance imaging/computed tomography scan findings in 115 patients with confirmed hereditary hemorrhagic telangiectasia (HHT) was conducted using the Hospital for Sick Children's HHT Clinic database for the years 1997-2012.

RESULTS

Eleven patients (four girls and seven boys) were diagnosed with hereditary hemorrhagic telangiectasia and brain arteriovenous malformations during this period. Five patients initially presented with epistaxis, four presented with intracranial hemorrhage, and two were asymptomatic with a positive family history of confirmed hereditary hemorrhagic telangiectasia. Although all children had an index case with hereditary hemorrhagic telangiectasia in the family, in three patients, hereditary hemorrhagic telangiectasia was not diagnosed before the child's presentation with intracranial hemorrhage. Multiple brain arteriovenous malformations were found in five patients, with one patient having bithalamic arteriovenous malformations.

CONCLUSIONS

This study highlights the importance of both family history and early clinical signs to prompt further diagnostic testing to avoid intracranial hemorrhage from brain arteriovenous malformations in children with hereditary hemorrhagic telangiectasia.

Hereditary hemorrhagic telangiectasia: arteriovenous malformations in children

OBJECTIVE

To evaluate the clinical features in a large cohort of pediatric patients with genetically confirmed hereditary hemorrhagic telangiectasia (HHT) and to identify possible predictors of arteriovenous malformation (AVM) onset or clinical significance.

STUDY DESIGN

Prospective cross-sectional survey of all children subjected to screening for AVMs in the multidisciplinary HHT center. All patients proved to be carriers of endoglin mutations or activin A receptor type-II-like kinase 1 mutations, defined as HHT1 and HHT2, respectively. A full clinical-radiological protocol for AVM detection was adopted, independent from presence or absence of AVM-related symptoms.

RESULTS

Forty-four children (mean age, 10.3 years; range, 1-18) were subjected to a comprehensive clinical-radiologic evaluation. This investigation disclosed cerebrovascular malformations in 7 of 44 cases, pulmonary AVMs in 20 of 44 cases, and liver AVMs in 23 of 44 cases. Large visceral AVMs were found in 12 of 44 children and were significantly more frequent in patients with HHT1. Only large AVMs were associated with symptoms and complications.

CONCLUSIONS

Children with HHT have a high prevalence of AVMs; therefore, an appropriate clinical and radiological screening protocol is advisable. Large AVMs can be associated with complications in childhood, whereas small AVMs probably have no clinical risk.

Rendu-Osler-Weber syndrome: what radiologists should know. Literature review and three cases report

Rendu-Osler-Weber syndrome or hereditary hemorrhagic telangiectasia is an autosomal dominant vascular disease involving multiple systems whose main pathological change is the presence of abnormal arteriovenous communications. Most common symptoms include skin and mucosal telangiectasias, epistaxis, gastrointestinal, pulmonary and intracerebral bleeding. The key imaging finding is the presence of visceral arteriovenous malformations. The diagnosis is based on clinical criteria and can be confirmed by molecular biology techniques. Treatment includes measures for management of epistaxis, as well as surgical excision, radiotherapy and embolization of arteriovenous malformations, with emphasis on endovascular treatment. The present pictorial essay includes a report of three typical cases of this entity and a literature review.

Term neonate with intracranial hemorrhage and hereditary hemorrhagic telangiectasia: a case report and review of the literature

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by mucocutaneous telangiectases and arteriovenous malformations (AVMs). The disease rarely presents in the neonatal period, primarily manifesting with epistaxis and gastrointestinal bleeding in adulthood. Occasionally, HHT can also present with symptoms related to AVMs in the cerebral, pulmonary or gastrointestinal vasculature. In prior reports, intracranial hemorrhage (ICH) secondary to cerebral AVM in neonates with HHT has been catastrophic and uniformly fatal. Here we report a case of a newborn with HHT and ICH from a suspected AVM who survived with aggressive medical management and surgical intervention, and provide a comprehensive review of the literature on ICH in neonates with HHT.

Utility of contrast echocardiography for pulmonary arteriovenous malformation screening in pediatric hereditary hemorrhagic telangiectasia

OBJECTIVE

To evaluate the utility of transthoracic contrast echocardiography (TTCE) as a screening tool for pulmonary arteriovenous malformations (PAVMs) in children with hereditary hemorrhagic telangiectasia (HHT).

STUDY DESIGN

This was a single-center study of children who underwent baseline screening for PAVMs using both TTCE and chest computed tomography (CT) for evaluation of HHT. The CT and TTCE results were prospectively reviewed independently by 2 radiologists and 2 cardiologists blinded to the study results.

RESULTS

Both intraobserver and interobserver agreement for interpreting TTCE results were excellent (κ = 0.97 and 0.92, respectively) and higher than the interobserver agreement for CT interpretation (κ = 0.75). The sensitivity and specificity of TTCE to predict PAVMs were 1 and 0.82, respectively, and the positive predictive and negative predictive values were 0.39 and 1, respectively.

CONCLUSION

TTCE is a sensitive test for PAVMs in children with suspected HHT and can be a useful initial screening tool in pediatric HHT.

Pulmonary Arteriovenous Malformation (AVM) Causing Tension Hemothorax in a Pregnant Woman Requiring Emergent Cesarean Delivery

Pulmonary arteriovenous malformations (PAVMs), although most commonly congenital, are usually detected later in life. We present a case of a 25-year-old woman with no previous history of AVM or telangiectasia, who presented with life-threatening hypoxia, hypotension, and pleuritic chest pain in 36th week of gestation. Chest tube placement revealed 4 liters of blood. Patient was subsequently found to have bleeding pulmonary AVM as the source of hemothorax. Successful embolisation of the bleeding vessel followed by thoracoscopic evacuation of the organized clot relieved the hypoxia. Further screening for AVM revealed large splenic AVM for which patient underwent splenectomy in the coming months.

Symptomatic liver involvement in neonatal hereditary hemorrhagic telangiectasia

High-flow hepatic vascular anomalies with arteriovenous shunting commonly manifest during the neonatal period with signs and symptoms of congestive heart failure, but to our knowledge, they have never been described in patients with hereditary hemorrhagic telangiectasia (HHT). We report here our experience with 3 patients with hepatic arteriovenous malformations (AVMs) who presented with symptoms of high-output congestive heart failure during the neonatal period and were subsequently diagnosed with HHT. Imaging showed large hypervascular lesions and multiple hepatic arteriovenous shunts that differentiated these lesions from liver hemangiomas. Transcatheter embolization was performed in all cases. One infant died of sepsis shortly after embolization; follow-up at the age of 2.5 years of the surviving infants revealed involution of the vascular lesions and no evidence of symptom recurrence. We conclude that severe symptoms related to hepatic AVMs in HHT can occur in the neonatal period and that HHT should therefore be included in the differential diagnosis of symptomatic neonatal hepatic vascular malformations. Imaging plays a key role in differentiating hepatic AVMs from hemangiomas, because the latter require additional pharmacologic treatments. Early transcatheter embolization seems to be effective, but long-term outcomes still need to be assessed.

The potential of capillary birthmarks as a significant marker for capillary malformation-arteriovenous malformation syndrome in children who had nontraumatic cerebral hemorrhage

BACKGROUND/PURPOSE

Capillary malformation-arteriovenous malformation (CM-AVM) is a new autosomal dominant disorder with cutaneous capillary malformations (CM) and high-flow cerebral arteriovenous malformations (AVM). Patients may have Parkes-Weber syndrome. This study determined if cutaneous CM are a significant indicator of CM-AVM in children with cerebral bleeds.

METHODS

Children with cerebral AVMs between 1991 and 2009 were reviewed. A family history of brain hemorrhage, AVMs, or cutaneous birthmarks was elicited. Patients and siblings were examined for CM and a family tree recorded. A brief questionnaire determined the family's opinion regarding screening for this syndrome.

RESULTS

Of 30 families, 1 family had Parkes-Weber syndrome. In 3 families, both patient and relatives had CM. In 9 families, patients had no CM, but relatives had them. One family had hereditary hemorrhagic telangiectasia. From the survey, 80% of families would be concerned about vascular marks, and 87% of families would allow screening for cerebral AVMs.

CONCLUSION

A family history of vascular marks may predict families at risk of having a cerebral AVM with hemorrhage. Most families would agree to screening. However, family history and physical examination alone do not confirm CM-AVM but form a useful screening tool to identify families needing further investigations with genetic testing and/or magnetic resonance imaging.

Effects of VEGF on phenotypic severity in children with hereditary hemorrhagic telangiectasia

The purpose of this study was to estimate vascular endothelial growth factor (VEGF) and transforming growth factor (TGF)-beta1 serum levels in children with hereditary hemorrhagic telangiectasia (HHT) type 1 and type 2 and to correlate them to the presence of arteriovenous malformations (AVMs). High VEGF levels were initially found in an infant who had been hospitalized with intestinal bleeding and suspected HHT. This case led to the evaluation of VEGF and TGF-beta1 by standard enzyme-linked immunosorbent assay in 13 children with HHT and familiarity. Patients were divided into 2 groups on the basis of the presence/absence of pulmonary AVMs. No significant difference was found for VEGF and TGF-beta1 levels in HHT patients versus controls. Among HHT patients, serum levels of VEGF in those without AVM were significantly lower than those with AVM and normal controls. No difference for TGF-beta1 levels was found in these patient subgroups. Low VEGF levels may represent a protection factor against the onset of pulmonary AVMs in HHT children. However, neither VEGF nor TGF-beta1 can be used as biochemical markers for an early diagnosis in HHT. The diagnosis of HHT still requires clinical criteria, which permitted to confirm the presence of the disease in the infant with intestinal bleeding.

Long-term follow-up in 12 children with pulmonary arteriovenous malformations: confirmation of hereditary hemorrhagic telangiectasia in all cases

OBJECTIVE

To assess whether pulmonary arteriovenous malformation (PAVM) is associated with hereditary hemorrhagic telangiectasia (HHT).

STUDY DESIGN

This study was a review of 12 children (sex ratio = 1) including family history, mutation analysis, and long-term follow-up.

RESULTS

Five children were under age 3 years when PAVM was diagnosed. Presentations included pulmonary symptoms (n = 8), cerebral abscess (n = 2), and transient ischemic attack (TIA) (n = 1); 1 patient was asymptomatic. Nine of the 12 children (75%) had a family history of PAVM. The diagnosis of HHT was confirmed in all cases. A mutation in ENG was found in 9 of the 10 children available for testing. No mutation in ACVRL1 was found. During long-term follow-up (mean, 16 years), the following complications occurred: TIA (n = 2), hemoptysis (n = 2), and cerebral abscess (n = 2). Nine children experienced recurrence of PAVM. The children with no recurrence were those without a family history of PAVM.

CONCLUSIONS

The diagnosis of HHT should be considered in a child with an apparently isolated PAVM. Because serious complications may occur at any age, we recommend screening for PAVM and long-term follow-up in children from families with HHT, especially those with an ENG mutation.

Hereditary hemorrhagic telangiectasia: clinical features in ENG and ALK1 mutation carriers

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder characterized by epistaxis, mucocutaneous telangiectases and visceral arteriovenous malformations (AVMs), particularly in the brain (CAVMs), lungs (PAVMs), liver (HAVMs) and gastrointestinal tract (GI). The identification of a mutated ENG (HHT1) or ALK-1 (HHT2) gene now enables a genotype-phenotype correlation.

OBJECTIVE

To determine the incidence of visceral localizations and evaluate phenotypic differences between ENG and ALK1 mutation carriers.

METHODS

A total of 135 consecutive adult patients were subjected to mutational screening in ENG and ALK1 genes and instrumental tests to detect AVMs, such as chest-abdomen multislice computed tomography (MDCT), brain magnetic resonance imaging and magnetic resonance angiography (MRI/MRA), upper endoscopy, were offered to all patients, independent of presence of clinical symptoms. The 122 patients with identified mutations were enrolled in the study and genotype-phenotype correlations were established.

RESULTS

PAVMs and CAVMs were significantly more frequent in HHT1 (75% vs. 44%, P < 0.0005; 20% vs. 0%, P < 0.002, respectively) and HAVMs in HHT2 (60% vs. 84%, P < 0.01). No age difference was found for PAVMs whereas HAVMs were significantly higher in older patients in both HHT1 and HHT2. Neurological manifestations secondary to CAVMs/PAVMs were found only in HHT1 patients, whereas severe liver involvement was detected only in HHT2. Respiratory symptoms were mainly detected in HHT1.

CONCLUSIONS

Our study evidences a higher visceral involvement in HHT1 and HHT2 compared with previous reports. HHT1 is more frequently associated with congenital AVM malformations, such as CAVMs and PAVMs whereas HHT2 predominantly involves the liver. The ENG gene should be first targeted for mutational screening in the presence of large PAVM in patients < 45 years.