The European Rare Disease Network for HHT Frameworks for management of hereditary haemorrhagic telangiectasia in general and speciality care

Hereditary haemorrhagic telangiectasia (HHT) is a complex, multisystemic vascular dysplasia affecting approximately 85,000 European Citizens. In 2016, eight founding centres operating within 6 countries, set up a working group dedicated to HHT within what became the European Reference Network on Rare Multisystemic Vascular Diseases. By launch, combined experience exceeded 10,000 HHT patients, and Chairs representing 7 separate specialties provided a median of 24 years' experience in HHT. Integrated were expert patients who focused discussions on the patient experience. Following a 2016-2017 survey to capture priorities, and underpinned by more than 40 monthly meetings, and new data acquisitions, VASCERN HHT generated position statements that distinguish expert HHT care from non-expert HHT practice. Leadership was by specialists in the relevant sub-discipline(s), and 100% consensus was required amongst all clinicians before statements were published or disseminated. One major set of outputs targeted all healthcare professionals and their HHT patients, and include the new Orphanet definition; Do's and Don'ts for common situations; Outcome Measures suitable for all consultations; COVID-19; and anticoagulation. The second output set span aspects of vascular pathophysiology where greater understanding will assist organ-specific specialist clinicians to provide more informed care to HHT patients. These cover cerebral vascular malformations and screening; mucocutaneous telangiectasia and differential diagnosis; anti-angiogenic therapies; circulatory interplays between anaemia and arteriovenous malformations; and microbiological strategies to counteract loss of normal pulmonary capillary function. Overall, the integrated outputs, and documented current practices, provide frameworks for approaches that augment the health and safety of HHT patients in diverse health-care settings.

Does severe bleeding in HHT patients respond to intravenous bevacizumab? Review of the literature and case series

BACKGROUND

Hereditary Haemorrhagic Telangiectasia (HHT) is an autosomal dominant genetic disorder, with a wide variety of clinical manifestations due to the presence of multiple arteriovenous manifestations. Severe bleeding from the gastrointestinal (GI) tract and/or epistaxis presents a significant problem in a subgroup of patients and systemic bevacizumab, an angiogenesis inhibitor, has been suggested to benefit these patients.

OBJECTIVE

To perform a review of the literature concerning the efficacy of systemic bevacizumab in treatment of bleeding from the nose or GI tract in patients with HHT, including patients from our own HHT-center.

METHODS

A literature review was performed using the guideline "Preferred Reporting Items for systematic Reviews and MetaAnalysis statement" (PRISMA).

RESULTS

After careful selection, we finally analysed the results of eight case series and 33 case reports. Among 195 patients 171 (88%) had reduced bleeding after bevacizumab.

CONCLUSIONS

Based on the literature review and data from our own case series, systemic bevacizumab is very promising as treatment for HHT patients with severe epistaxis and/or GI-bleeding. However, care should be taken using bevacizumab, a potent angiogenesis inhibitor; long-term side effects have not been studied in this population. A randomized controlled study is warranted to support the results in HHT patients.

Pulmonary arteriovenous malformations: a radiological and clinical investigation of 136 patients with long-term follow-up

AIM

To assess the clinical outcome of patients with and without hereditary haemorrhagic telangiectasia (HHT) after embolisation of pulmonary arteriovenous malformations (PAVM) from a single national centre.

MATERIALS AND METHODS

The present register-based observational study including all patients with PAVM treated with embolisation at a reference centre for HHT and PAVM was undertaken over a 20-year period. Demographic data, HHT genotyping, clinical presentation, and outcome were registered. Patients with HHT were compared to the patients without HHT. Clinical examination, contrast-enhanced echocardiography, and computed tomography (CT) were used to assess the clinical outcome at follow-up.

RESULTS

One hundred and thirty-six patients with 339 PAVM underwent embolisation during the study period: 22 did not have HHT; 62% had HHT1, 10% had HHT2, 4% had JP-HHT, 8% had clinical HHT without identified genetic mutations. Solitary PAVM were more common among patients without HHT than with HHT. Mean follow-up after the first embolisation was 58 months. Mean age at first embolisation was 46.5 years, and at last follow-up 51.8 years. The clinical success without shunt at follow-up was 87%. The 30-day mortality related to the embolisation was 0%. Twenty patients died during follow-up (mean age 69 years). Most patients could be treated during one session, but many will need a long follow-up with repeated clinical examinations and embolisation.

CONCLUSION

The majority of patients referred for embolisation of PAVM had HHT. Multiple PAVM is associated with HHT. Patients with PAVM should be screened for HHT and patients with HHT for PAVM. Embolisation is a safe procedure with high clinical success.

Middle ear disease in Danish toddlers attending nursery day-care - Applicability of OM-6, disease specific quality of life and predictors for middle ear symptoms

OBJECTIVES

Otitis media (OM) is a very common childhood disease and impacts child quality of life (QoL) to different extends. The aim of this study was to investigate the difference in quality of life between three groups of children; Children with symptoms of ear disease within the last 4 weeks, children without any ear disease and children scheduled for ventilating tube treatment. Furthermore, we investigated predictors for experiencing middle ear symptoms. Lastly, we assessed psychometric properties of OM-6 used to assess QoL.

METHODS

Four hundred ninety-four children attending nursery day-care aged 6-36 months were enrolled in the study. Caregivers were asked to recall the child's history of symptoms related to middle ear infection. The Danish version of otitis media-6 questionnaire was used to measure the children's quality of life. Data from children treated with ventilating tubes were included from a previously published study. Logistic regression was applied for determining possible predictors for experiencing ear related symptoms.

RESULTS

The study had an 87% response rate, with a total of 342 children included. At the inclusion 32 (9%) children were included in the 4-week group and, while 307 children were allocated to the non-4 week group. The children in the 4-week group were significantly younger and were more likely to have siblings with a history of middle ear infection than the non-4week group. Furthermore, QoL was significantly worse in the 4-week group compared to the non-4week group. Only subtle differences were found between children with acute symptoms compared to children scheduled for tube treatment.

CONCLUSIONS

As expected, children with acute symptoms of OM experience lowered QoL compared to children with no symptoms and young age as well as having siblings with a history of middle ear problems were found to be possible predictors for experiencing middle ear symptoms. Children with acute symptoms differed from children scheduled for ventilating tubes on domains related to long-term problems from OM. OM-6 has shown to be a valid instrument for assessing disease specific QoL in children with OM, however a more large-scale instrument might be necessary for detecting subtle differences between subgroups of children with OM.

The validity of nasal endoscopy in patients with chronic rhinosinusitis-An inter-rater agreement study

OBJECTIVES

Nasal endoscopy is a cornerstone in diagnosing sinonasal disease, but different raters might generate different results using the technique. Our study aims to evaluate the agreement between multiple raters to assess the validity of nasal endoscopy.

DESIGN/PARTICIPANTS

Three independent and blinded raters evaluated 28 patients (56 nasal cavities) diagnosed with chronic rhinosinusitis according to the European Position Paper on Rhinosinusitis and Nasal Polyps. The ratings were compared using unweighted Fleiss' kappa coefficients (K_f ) for each objective parameter.

SETTING

The department of Otorhinolaryngology, Odense University Hospital, Denmark.

MAIN OUTCOME MEASURES

The ratings were quantified in a modified Lund-Kennedy endoscopy score and focused on the objective parameters specified in the diagnostic criteria: polyps, oedema and discharge.

RESULTS

The raters agreed on the findings concerning polyps and discharge but not regarding oedema with the inter-rater agreement for the different parameters being: polyps K_f =.66 (SE .07, P<.001), oedema K_f =.05 (SE .07, P=.21), discharge K_f =.35 (SE .08, P<.001), oedema exclusively in middle meatus K_f =-.07 (SE .04, P=.8) and discharge exclusively in middle meatus K_f =.16 (SE .07, P=.01).

CONCLUSION

Using nasal endoscopy, the evaluation of polyps by multiple raters showed sufficient reliability indicating an acceptable objective evaluation. The evaluation of discharge achieved a fair level of agreement while the assessment of oedema could not achieve a sufficient reliability questioning the inclusion of oedema in the criteria for diagnosing sinonasal disease.

Prevalence of hereditary hemorrhagic telangiectasia in patients operated for cerebral abscess: a retrospective cohort analysis

It is well described that patients with pulmonary arteriovenous malformations (PAVMs) and Hereditary Hemorrhagic Telangiectasia (HHT) have an increased risk of cerebral abscess (CA). However, as both CA and HHT are rare, the proportion of patients with CA who are diagnosed with HHT has not been previously described. A retrospective study was carried out of all patients treated surgically for CA between January 1995 and September 2014 at the Department of Neurosurgery, Odense University Hospital. The cases were then cross-referenced with the Danish HHT database. Eighty patients aged 5-79 years were included. The incidence of CA was 0.33/100,000/year. Two patients (2.5%) were registered as having HHT. Bacterial pathogens were identified in 70% of all cases, most frequently streptococci species (46.3%). The most common predisposing condition was odontogenic infection (20%), followed by post-operative infection (13.8%) and post-trauma (6.3%). Patients undergoing a full diagnostic program to determine predisposing conditions causing CA increased over the 20-year period from 11.8% to 65.2%. The 3-month and 1-year mortality rates were 7.5% and 11.25%, respectively. There is an overrepresentation of HHT patients in a cohort of patients with CA, and HHT should be investigated as the cause of the CA if no other apparent cause can be identified.

Efficacy of ESS in chronic rhinosinusitis with and without nasal polyposis: a Danish cohort study

Endoscopic sinus surgery (ESS) for patients with severe chronic rhinosinusitis (CRS) has become a well-established treatment in cases where medical therapy fails. Even though CRS patients are divided into two subgroups, CRS with nasal polyposis (CRSwNP) and CRS without nasal polyposis (CRSsNP), most studies present only results for the total cohort. This prospective cohort study evaluated the efficacy of ESS on both quality of life and olfactory function measures, in a cohort of Danish CRS patients diagnosed according to the EPOS criteria, with results analysed separately for the CRSwNP and CRSsNP subgroups. All 97 CRS patients who underwent ESS over an 18-month trial period were evaluated preoperative by SNOT-22 score, Sniffin' Sticks score, modified Lund-Kennedy endoscopic score and Lund-Mackay CT score. Patient outcomes were reevaluated at clinical follow-up 1 and 6 months postoperative. ESS efficiently and immediately improved quality of life for both CRSwNP and CRSsNP patients, with over 50 % reduction in SNOT-22 score 1 month after surgery, which sustained 6 months postoperative. Olfactory function measured by Sniffin' Sticks score showed overall improvement in both groups. ESS efficiently improved quality of life in both CRSwNP and CRSsNP patients, and surgery lead to an overall improvement in olfactory function. However, a minor proportion of patients experienced deterioration in olfactory function after ESS.

Cerebral abscesses among Danish patients with hereditary haemorrhagic telangiectasia

BACKGROUND

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease characterized by a wide variety of clinical manifestations, including pulmonary arteriovenous malformations (PAVMs), which due to paradoxical embolization may cause cerebral abscess.

OBJECTIVE

To estimate the risk of cerebral abscess among patients with HHT.

METHODS

All patients with HHT included in the Danish HHT data base, between January 1995 and October 2012, have been clinically evaluated for the presence of neurological symptoms and history of previous cerebral abscess.

RESULTS

A total of 337 patients with HHT have been included in the Danish database. Of these, 264 were screened for the presence of PAVM. In 117 patients, a PAVM was diagnosed; among these, we identified nine patients with a history of cerebral abscess. The prevalence of cerebral abscess among patients with HHT and PAVM was therefore 7.8%. The patients with a history of cerebral abscess were genetically evaluated, and seven had ENG mutations, one had an ALK1 mutation, and in one case, a mutation could not be identified.

CONCLUSION

Patients with untreated PAVM have a considerable risk of sustaining cerebral abscesses. A cerebral abscess may be the first symptom leading to an HHT diagnosis. Patients with unexplained cerebral abscess should be evaluated for HHT and PAVM.

Occlusion of pulmonary arteriovenous malformations by use of vascular plug

Pulmonary arteriovenous malformations are commonly treated by embolization with coils or balloons to prevent cerebral complications and to raise the oxygenation of the blood. The Amplatzer vascular plug is a new occlusive device made of a self-expanding cylindrical nitinol mesh. It is fast and safe to position, and can be repositioned before final delivery. It is especially suited for embolization of large high-flow vessels as in pulmonary arteriovenous malformations with big feeding arteries. Two cases of successful use of the new device for treatment of large pulmonary arteriovenous malformations are described.

Mutations in endoglin and in activin receptor-like kinase 1 among Danish patients with hereditary haemorrhagic telangiectasia

Hereditary haemorrhagic telangiectasia (HHT) is a rare disorder with one per 6000-10,000 affected individuals in the general Caucasian population. HHT is genetically heterogeneous, involving at least two loci HHT1 mapping to chromosome 9q34.1 and HHT2 mapping to chromosome 12q31. The loci have been identified as endoglin (ENG) and activin receptor-like kinase 1 (ALK1). In order to gain knowledge of the genotype distribution and prevalence in the Danish population and to establish a reproducible and sensitive molecular genetic test method, we developed a denaturating gradient gel electrophoresis protocol for mutation scanning of the two loci. Twenty-five Danish HHT families were tested. A total of eight new as well as seven previously reported mutations were identified. A founder mutation was characterized present in seven families and possibly introduced around 350 years ago. In one individual, a presumed spontaneous mutation was characterized. The method developed proved to be very sensitive for mutation detection in both ENG and ALK1. Genetic screening in HHT families facilitates an early treatment strategy for silent HHT manifestations in first degree relatives.

Clinical symptoms according to genotype amongst patients with hereditary haemorrhagic telangiectasia

BACKGROUND

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease, characterized by a wide variety of clinical manifestations, including epistaxis, gastrointestinal (GI) bleeding, pulmonary arteriovenous malformations (PAVMs) and neurological symptoms. HHT is a genetically heterogeneous disorder involving at least two loci; HHT 1 mapping to chromosome 9 q 34.1 (ENG) and HHT 2 mapping to chromosome 12 q 31 (ALK-1).

OBJECTIVE

To evaluate and describe the diversity of clinical manifestations in a Danish population of HHT patients with known HHT 1 or HHT 2 subtype.

DESIGN

Prospective clinical examination with genetic evaluation and follow-up.

SETTING

Investigation centre was Odense University Hospital. All HHT patients in the County of Fyn were included.

METHODS

HHT family members were invited to a clinical examination including registration of HHT manifestations, screening for PAVM and neurological evaluation. Blood tests were performed for analysis of disease-causing mutation, and clinical manifestations in the HHT subtypes were compared. The survival of the patients was studied in the follow-up period.

RESULTS

Included in the study were 73 HHT patients representing 18 families. In 14 of the families we identified a disease-causing mutation. Thirty-nine patients (from 10 families) had HHT1 and 16 HHT patients from four families had HHT2.

CONCLUSION

Amongst patients with HHT1 genotype the prevalence of PAVM was higher than amongst HHT patients with HHT2 genotype. HHT1 patients had experienced more severe GI bleeding than HHT2 patients. There was no significant difference in severity of epistaxis or age at debut. Finally the mortality over a 90-month observation period was not significantly increased.

[Pulmonary arteriovenous malformations. Current therapeutic principles]

Pulmonary arteriovenous malformations are congenital vascular malformations in the lungs, which act as shunts so that the blood is not oxygenated or filtered. These patients are typically hypoxaemic with exercise intolerance and are at high risk of paradoxical emboli to the brain. About 25% of patients with the Rendu-Osler-Weber syndrome (hereditary haemorrhagic telangiectasia) have these pulmonary malformations. A modern treatment strategy is embolisation with balloon or coils of the afferent arteries to the arteriovenous malformations. It is a minimally invasive procedure with a very high technical success and few complications. Embolisation prevents cerebral stroke and abscess and pulmonary haemorrhage and further raises the functional level. Screening for pulmonary arteriovenous malformations in patients at risk is recommended.

Tympanoplasty with ionomeric cement

Patients with isolated erosion of the long incus process suffer from severe hearing loss caused by lack of continuity of the ossicular chain. This study is a retrospective evaluation of the hearing results using two different surgical procedures. Since January 1993, 12 consecutive patients with isolated erosion of the long incus process have been treated with a new surgical technique in which the ossicular chain was rebuilt with ionomeric cement. The results in hearing performance (mean pure-tone average (PTA) 0.5, 1 and 2 kHz) were evaluated pre- and post-surgery, and compared to those in a group of 20 historical controls who underwent surgery in 1991 and 1992 using incus autograft interposition. Among the 12 index patients, 7 (58%) achieved improvement in PTA of > 10 dB, in 3 there was no difference and in 2 a slight decline. Among the 20 controls, 14 (70%) achieved improvement in PTA of > 10 dB, in 4 there was a slight improvement and in 2 a decline. The difference was not statistically significant. Hearing improvement using ionomeric cement in type II tympanoplasty was satisfactory. Reconstruction of the ossicular chain with ionomeric cement is recommended, as the procedure is easy to perform, presents less risk of damage to the stapes and cochlea, requires less extensive surgery and does not exclude other surgical methods in cases of reoperation.

[Percutaneous transluminal embolization of pulmonary arteriovenous malformations]

OBJECTIVE

The aim was to evaluate the effect of embolisation of pulmonary arteriovenous malformations (PAVM), as estimated by contrast echocardiography, arterial blood-gas analyses and functional level, and further to evaluate procedure-related and late complications.

PATIENTS AND METHODS

Seventeen patients were treated on 25 occasions for a total of 48 PAVM. Fifteen patients had hereditary haemorrhagic telangiectasia (HHT). Chest X-ray, pulmonary angiography, contrast echocardiography, arterial blood-gas analyses, and functional level were analysed before and after embolisation of PAVM. The mean follow-up period was 22 months.

RESULTS

Contrast intensity at contrast echocardiography decreased from median 4.0 (range 2-4) before embolisation to 1.5 after embolisation. PaO2 breathing 100% oxygen increased from mean 271 mm Hg before embolisation to 480 mm Hg after embolisation. The shunt was reduced from mean 24% before to 12% after embolisation. Most of the patients experienced an increased functional level after embolisation, and the median functional level (NYHA) increased from NYHA 2.5 to 1.2. No primary or secondary device migration, no cerebral insults, and no mortality was noted.

CONCLUSION

Embolisation is a well-established method of treating PAVM, with a significant effect on oxygenation of the blood. It is a minimally invasive, lung-preserving treatment with high affectiveness and low morbidity and mortality. Patients with HHT should be screened for PAVM as a high percentage of these have PAVM.

Mutations in the ALK-1 gene and the phenotype of hereditary hemorrhagic telangiectasia in two large Danish families

Mutations in the ENG gene on chromosome 9 (HHT 1) and in the ALK-1 gene on chromosome 12 (HHT 2) have been reported as causes of hereditary hemorrhagic telangiectasia (HHT). HHT 1 has been correlated with a higher prevalence of pulmonary arteriovenous malformations than HHT 2. Other distinct phenotype-genotype correlations have not been described. The prevalence of HHT in the county of Fyn, Denmark, was 15.6 per 100,000 on January 1, 1995. All living patients and their first-degree relatives were invited to attend a detailed clinical examination and blood was drawn for mutation analysis. In two families mutations were identified in exon 8 of the ALK-1 gene. In family 6 we found a T1193A mutation. In this family a high prevalence of PAVM and severe GI bleeding was documented, while in family 8 with a C1120T mutation no individuals with PAVM were identified and only one patient had a history of severe GI bleeding. No mutations in the endoglin locus were found in either family.

Prevalence of pulmonary arteriovenous malformations (PAVMs) and occurrence of neurological symptoms in patients with hereditary haemorrhagic telangiectasia (HHT)

BACKGROUND

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease. HHT is characterized by a wide variety of clinical manifestations, including pulmonary arteriovenous malformations (PAVMs) and neurological symptoms.

OBJECTIVE

To estimate (i) the prevalence of PAVM, and (ii) the occurrence of neurological symptoms in a geographical well-defined population of HHT patients.

METHODS

HHT family members were invited to a clinical examination including registration of HHT manifestations, screening for pulmonary arteriovenous malformations and neurological evaluation. Two groups served as controls: (i) first-degree relatives without any signs of HHT; and (ii) age- and gender-matched controls.

SETTING

Odense University Hospital.

SUBJECTS

HHT patients identified in a cross-sectional family survey carried out in the County of Fyn, Denmark.

RESULTS

Included in the study were 169 HHT family members representing 24 families. They included both HHT patients and their first-degree relatives. The criteria of HHT were fulfilled in 75 participants; of these, 59 had a screening procedure performed, and PAVMs were demonstrated at pulmonary angiography (PA) in 18. Seven of the HHT patients had a history of cerebral stroke, compared with none of their healthy first-degree relatives.

CONCLUSION

The prevalence of PAVM was 24% amongst HHT patients. The study confirmed an increased prevalence of neurological symptoms amongst HHT patients; the odds ratio was estimated to be 7.6. In order to enable prevention of these complications, screening for PAVM should become an integral part of the medical care for HHT patients.

[Hereditary hemorrhagic telangiectasia. A population-based study on prevalence and mortality among Danish HHT patients]

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease characterized by telangiectatic lesions. The disease manifestations are variable in severity. Early death due to complications has been described. We report an investigation of the prevalence and mortality of HHT in a Danish population, based on two cross-sectional surveys in combination with a long-term follow-up study. The prevalence of HHT in the county of Funen was 13.8 per 100,000 January 1. 1974 and 15.6 per 100,000 January 1. 1995. In the HHT group as a whole we found a slightly increased mortality, however among the HHT patients younger than 60 years at inclusion the mortality of HHT patients was twice the expected. The excess mortality was fully explained by severe HHT symptoms contributing to death. Future research should aim at identification of HHT patients at particular risk of developing severe complications.

Screening for pulmonary arteriovenous malformations: contrast echocardiography versus pulse oximetry

Pulmonary arteriovenous malformations (PAVM) cause right-to-left shunt and imply risk of paradoxical embolism and cerebral abscess. These complications can be prevented by appropriate treatment. Detection of PAVMs is therefore important, so simple and reliable screening methods are needed for this purpose. The aim of this investigation was to compare pulse oximetry and contrast echocardiography as screening tools for detection of pulmonary arteriovenous malformations. Eighty-five hereditary haemorrhagic telangiectasia (HHT) patients and first-degree relatives identified in a comprehensive study of HHT-families in the county of Funen, Denmark, were investigated. Standing and supine pulse oximetry in room air was performed in all subjects, and in subjects with symptoms and/or abnormal pulse oximetry in room air, supine pulse oximetry breathing 100% oxygen was also performed. Transthoracic echocardiography with intravenous injection of echo contrast was performed in all subjects. Outcome measures were oxygen saturation change >2% units on changing body position and echo contrast observed in the left-sided heart chambers. Positive contrast echocardiography indicating the presence of PAVM was found in 47 subjects, whereas pulse oximetry was abnormal in only 16. The results strongly suggest that contrast echocardiography is a more sensitive screening tool for PAVMs than pulse oximetry.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous malformations, particularly in the pulmonary circulation, are unrecognized and left untreated. In spite of the identification of two of the disease-causing genes (endoglin and ALK-1), only a clinical diagnosis of HHT can be provided for the majority of individuals. On behalf of the Scientific Advisory Board of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot be established in patients with only two criteria, but should be recorded as possible or suspected to maintain a high index of clinical suspicion. If fewer than two criteria are present, HHT is unlikely, although children of affected individuals should be considered at risk in view of age-related penetration in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous malformations, particularly in the pulmonary circulation, are unrecognized and left untreated. In spite of the identification of two of the disease-causing genes (endoglin and ALK-1), only a clinical diagnosis of HHT can be provided for the majority of individuals. On behalf of the Scientific Advisory Board of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot be established in patients with only two criteria, but should be recorded as possible or suspected to maintain a high index of clinical suspicion. If fewer than two criteria are present, HHT is unlikely, although children of affected individuals should be considered at risk in view of age-related penetration in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous malformations, particularly in the pulmonary circulation, are unrecognized and left untreated. In spite of the identification of two of the disease-causing genes (endoglin and ALK-1), only a clinical diagnosis of HHT can be provided for the majority of individuals. On behalf of the Scientific Advisory Board of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot be established in patients with only two criteria, but should be recorded as possible or suspected to maintain a high index of clinical suspicion. If fewer than two criteria are present, HHT is unlikely, although children of affected individuals should be considered at risk in view of age-related penetration in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous malformations, particularly in the pulmonary circulation, are unrecognized and left untreated. In spite of the identification of two of the disease-causing genes (endoglin and ALK-1), only a clinical diagnosis of HHT can be provided for the majority of individuals. On behalf of the Scientific Advisory Board of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot be established in patients with only two criteria, but should be recorded as possible or suspected to maintain a high index of clinical suspicion. If fewer than two criteria are present, HHT is unlikely, although children of affected individuals should be considered at risk in view of age-related penetration in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous malformations, particularly in the pulmonary circulation, are unrecognized and left untreated. In spite of the identification of two of the disease-causing genes (endoglin and ALK-1), only a clinical diagnosis of HHT can be provided for the majority of individuals. On behalf of the Scientific Advisory Board of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot be established in patients with only two criteria, but should be recorded as possible or suspected to maintain a high index of clinical suspicion. If fewer than two criteria are present, HHT is unlikely, although children of affected individuals should be considered at risk in view of age-related penetration in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years.

Diagnostic criteria for hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

Hereditary Hemorrhagic Telangiectasia (HHT) is easily recognized in individuals displaying the classical triad of epistaxis, telangiectasia, and a suitable family history, but the disease is more difficult to diagnosis in many patients. Serious consequences may result if visceral arteriovenous malformations, particularly in the pulmonary circulation, are unrecognized and left untreated. In spite of the identification of two of the disease-causing genes (endoglin and ALK-1), only a clinical diagnosis of HHT can be provided for the majority of individuals. On behalf of the Scientific Advisory Board of the HHT Foundation International, Inc., we present consensus clinical diagnostic criteria. The four criteria (epistaxes, telangiectasia, visceral lesions and an appropriate family history) are carefully delineated. The HHT diagnosis is definite if three criteria are present. A diagnosis of HHT cannot be established in patients with only two criteria, but should be recorded as possible or suspected to maintain a high index of clinical suspicion. If fewer than two criteria are present, HHT is unlikely, although children of affected individuals should be considered at risk in view of age-related penetration in this disorder. These criteria may be refined as molecular diagnostic tests become available in the next few years.

Gastrointestinal bleeding in patients with hereditary hemorrhagic telangiectasia

OBJECTIVE

Gastrointestinal bleeding occurs in a number of patients with hereditary hemorrhagic telangiectasia (HHT) and may lead to a high transfusion need. The aim of this study was to estimate the occurrence and severity of gastrointestinal bleeding in a geographically well defined HHT population.

METHODS

All HHT families in the county of Fyn, Denmark, (470,000 population) have been identified. Probands and their first degree relatives, and all descendants from probands for whom one parent had HHT were eligible for inclusion in the study. A total of 77 patients with HHT were identified; of these, 76 patients (mean age: 52 yr) were evaluated and interviewed with regard to gastrointestinal bleeding, that is, a history of either hematemesis or melena. Patients charts were reviewed.

RESULTS

A total of 25 HHT patients (33%) had a history of either hematemesis or melena. Of these, 12 (48%) had received blood transfusions. Seven patients had severe bleeding (that is, > or =6 units of blood within 6 months before inclusion in the study). Endoscopy had been performed in 16 of the 25 (64%) patients. Telangiectatic lesions were documented in nine at upper endoscopy and in one at sigmoidoscopy. Telangiectatic lesions were observed in all patients with severe bleeding, but in two patients epistaxis is likely to have contributed to the anemia. Among 51 HHT patients without a history of gastrointestinal bleeding, only five (10%) had previously received blood transfusions; however, none fulfilled the definition of severe bleeding. In the HHT population 29 patients were > or =60 yr old, but all patients with severe bleeding were > or =60 yr.

CONCLUSIONS

A history of gastrointestinal bleeding is common in patients with HHT (33%). This study documents that 25% of HHT patients > or =60 yr suffer from severe gastrointestinal bleeding.

Pulmonary arteriovenous malformations: screening procedures and pulmonary angiography in patients with hereditary hemorrhagic telangiectasia

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a dominantly inherited disease with a high prevalence of pulmonary arteriovenous malformations (PAVMs). The first symptom of HHT may be stroke or fatal hemoptysis associated with the presence of PAVM.

OBJECTIVE

To evaluate different screening methods applied for the identification of PAVMs.

SETTING

Odense University Hospital.

SUBJECTS

HHT patients with positive findings on contrast echocardiography (CE) who participated in a screening investigation and underwent pulmonary angiography (PA).

METHODS

Different screening methods were evaluated against the results of PA. In a group of patients with positive findings on CE, we compared results of PA with the following: severity of dyspnea; results of pulse oximetry arterial oxygen saturation (SaO2) supine and upright; supine PaO2 in room air and while breathing 100% oxygen; size of arteriovenous shunt in supine position; chest radiograph; and intensity of contrast at CE.

RESULTS

PA was performed in 25 HHT patients with positive findings on CE, 15 of whom had PAVM. Embolization therapy was recommended in 12 patients, and 3 patients had small PAVMs not accessible for therapy. In 10 patients, PAVM could not be demonstrated at PA. The sensitivity and specificity calculated for the screening procedures are as follows: 53% and 90%, respectively, for SaO2; 60% and 100%, respectively, for chest radiograph; 73% and 80%, respectively, for PaO2 in room air; 100% and 40%, respectively, for PaO2 breathing 100% oxygen; and 64% and 80%, respectively, for shunt measurement.

CONCLUSION

Initial screening with CE followed by measurement of PaO2 while breathing 100% oxygen seemed to be the best screening procedure for identification of patients with PAVM. Screening with chest radiograph and pulse oximetry was shown to be insufficient.

Hereditary haemorrhagic telangiectasia: a population-based study of prevalence and mortality in Danish patients

INTRODUCTION

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease characterized by telangiectatic lesions. The disease manifestations are variable and include epistaxis, gastrointestinal bleeding, pulmonary arteriovenous malformations and cerebral arteriovenous malformations. Early death due to these complications has been described.

DESIGN

We report a study on the prevalence and mortality of HHT in a Danish population based on two cross-sectional surveys in combination with a long-term follow-up study.

SETTINGS AND SUBJECTS

Prevalent cases of HHT as of 1 January 1974 in the County of Fyn, Denmark, were identified. In 1995-97 a follow-up study of mortality was performed of the initial patient sample, and a new point prevalence rate of HHT as of 1 January 1995 was calculated. All live patients and their families were invited to attend a detailed clinical examination.

RESULTS

The prevalence of HHT in the County of Fyn was 13.8 per 100,000 on 1 January 1974 and 15.6 per 100,000 on 1 January 1995. In the HHT group as a whole, we found a slightly increased mortality; however, amongst the HHT patients younger than 60 years at inclusion the mortality of HHT patients was twice the expected. The excess mortality could be fully explained by severe HHT symptoms.

CONCLUSION

This study suggests that HHT is more prevalent than previously believed. In young patients the disease is associated with an excess mortality which is fully attributable to HHT. Future research should aim at the identification of HHT patients at particular risk of developing severe complications.

Embolotherapy for pulmonary arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome)

PURPOSE

To evaluate the clinical results of embolization of pulmonary arteriovenous malformations (PAVMs) in patients with hereditary hemorrhagic telangiectasia (HHT), the Rendu-Osler-Weber syndrome.

MATERIAL AND METHODS

Twelve patients in the county of Fyn, Denmark, were treated with transcatheter embolization of 20 PAVMs using 12 detachable silicone balloons and 26 steel coils.

RESULTS

All PAVMs were completely occluded and we observed a significant rise in PaO2 after treatment and a significant decrease in right-to-left shunt estimated by contrast echocardiography. All patients experienced an improved functional level. One patient experienced severe pleurisy and another a rise in temperature following treatment, but otherwise no symptomatic complications were observed.

CONCLUSION

Embolotherapy is a definitive treatment for PAVMs: it is very effective with a high success rate and few complications. Patients with HHT are at risk of PAVM and should be screened and treated for PAVMs when these reach a size that is associated with complications. In the detection of PAVMs, contrast echocardiography is a very sensitive method, and follow-up of these patients can be done with contrast echocardiography.

[Percutaneous transluminal embolization of pulmonary arteriovenous malformations]

A series of nine patients with pulmonary arteriovenous malformations (PAVM) treated with embolotherapy at Odense University Hospital is presented. In all patients the arterial oxygen tension increased after embolisation. PAVM causes right-to-left shunting, which may result in severe hypoxaemia, and, due to lack of the normal filter function of the lung, paradoxical embolism. Women are particularly at risk during pregnancy. Among patients with Hereditary Haemorrhagic Telangiectasia 15-33% also have PAVM. Embolotherapy is a safe and efficacious treatment for occlusion of PAVM. Since serious complications to the disease can be prevented, all HHT patients should be offered screening for PAVM, and treated if required.

Group specific component in serum and otosclerosis: no association

An earlier Swedish study suggested a positive association between otosclerosis and the group-specific component GC*1F marker. We investigated the distribution of GC subtypes in 101 Danish patients with otosclerosis who all had surgery performed in the county of Funen. Compared to 1674 Danish controls we found no evidence of any association between markers from the GC serum protein system and otosclerosis.