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Hereditary Hemorrhagic Telangiectasia

HHT

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disease, characterized by abnormal blood vessel formation. It manifests principally with telangiectatic lesions and arteriovenous malformations and results in bleeding and blood shunting.


Presentation

Patients most commonly present with telangiectatic formations on their lips, face, oral mucosa and the tips of toes and fingers. These lesions can also be present in the gastrointestinal tract and nasal mucosa, resulting in severe GI bleeding or recurrent nosebleeds. Arteriovenous malformations can also occur in the lungs, leading to the formation of fistulas and right-to-left shunts. Right-sided cardiac stress may subsequently manifest with fatigue, shortness of breath and cyanosis [13].

HHT can have a sudden and acute neurological presentation. Patients may suffer from transient ischemic attacks, strokes and brain abscesses. Some forms of the disease are characterized by spinal and brain arteriovenous malformations with subsequent subarachnoid hemorrhaging, seizures or paralysis. AVMs can also occur in the liver and lead to high-output failure of the heart [14].

Anemia
  • Bevacizumab, a VEGF inhibitor, reduces epistaxis, telangiectasias, and iron-deficiency anemia. We present the case of a woman with HHT and chronic gastrointestinal bleeding who required iron supplementation and multiple blood transfusions.[ncbi.nlm.nih.gov]
  • CONCLUSION: Arrhythmias are the most common cardiac phenotype in HHT, and likely to be aggravated by iron deficiency anemia, its treatments, and/or high output states due to AVMs.[ncbi.nlm.nih.gov]
  • Bleeding and anemia were the most common complications. Molecular analysis was conducted in 4 patients. Only 1 patient was found to have a single-base deletion in ENG gene. The mean duration of follow-up of the patients was 41.8 months.[ncbi.nlm.nih.gov]
  • Hemorrhagic digestive telangiectases increase with age and can worsen chronic anemia.[orpha.net]
  • Epistaxis is one of the most common symptoms of HHT, and chronic, frequently relapsing epistaxis can cause symptoms such as iron deficiency anemia, severe crusting, and nasal obstruction that can cause lower quality of life.[ncbi.nlm.nih.gov]
Weakness
  • One year ago, the patient was hospitalized due to right-sided weakness, which was caused by left basal ganglia hemorrhage as the part of HHT presentation.[ncbi.nlm.nih.gov]
  • Due to repeated blood loss, patients with the condition also tend to have a shortage of red blood cells (anemia), which can cause fatigue, weakness and pale skin.[cedars-sinai.edu]
  • They result from weak perivascular connective tissue as well as disrupted endothelial junctions and degeneration.[symptoma.com]
  • This might cause you to feel tired or weak and to have less energy to exercise. Sometimes, your skin might have a bluish tint, especially in your lips, "clubbing" of the fingernails, and decreased blood oxygen levels.[mountsinai.org]
  • If the bleeding occurs into the subarachnoid space (subarachnoid hemorrhage), there is usually a severe, sudden headache and decreased level of consciousness and often weakness in part of the body.[en.wikipedia.org]
Dyspnea
  • He has not experienced worsening hypoxemia or dyspnea and has not developed PAVMs.[ncbi.nlm.nih.gov]
  • We report a case of a 74-year-old man who presented with dyspnea and hypoxia and was found to have a large right-sided PAVM. He underwent percutaneous closure of the PAVM with an Amplatzer device with significant improvement of his symptoms.[ncbi.nlm.nih.gov]
  • Furthermore, 6 of the NYHA class III dyspnea changed to class II 6 months after the beginning of the treatment.[doi.org]
  • However, pulmonary function tests are helpful in determining whether other causes of dyspnea and hypoxemia are present.[clinicaladvisor.com]
  • High-output heart failure typically presents in the seventh decade with nonspecific symptoms such as exertional dyspnea and lower-extremity edema, 9, 13 and tends to affect females more than males.[phaonlineuniv.org]
Melena
  • In this report, we presented a Chinese patient with recurrent melena due to gastric angiodysplasia in HHT treated successfully with thalidomide.[ncbi.nlm.nih.gov]
  • We report here the case of a 63 year-old male patient who presented melena and GI bleeding episodes, proven to be caused by bleeding from multiple gastric angiodysplasia.[ncbi.nlm.nih.gov]
  • Two patients were treated systemically with thalidomide, and their symptoms of epistaxis, melena, and anemia were notably improved.Patients with HHT have variable clinical characteristics, and their diagnoses were delayed on average by about 26 years.[ncbi.nlm.nih.gov]
  • […] autosomal dominant vascular anomaly characterized by the presence of multiple small telangiectases of the skin, mucous membranes, gastrointestinal tract, and other organs associated with recurrent episodes of bleeding from affected sites and gross occult melena[medical-dictionary.thefreedictionary.com]
  • He also reported melena stools. Following transfusion and stabilization he was re-assessed in our outpatient Otolaryngology- Head & Neck Surgery clinic where management with septodermoplasty was entertained to address the epistaxis.[link.springer.com]
Black Stools
  • Some commons signs of HHT include recurring/frequent nosebleeds, telangiectases that appear on the skin’s surface in your 30s and 40s, black stools, back pain and loss of feeling in the arms and legs.[my.clevelandclinic.org]
  • Symptoms of this syndrome include: Frequent nosebleeds in children Bleeding in the gastrointestinal tract (GI), including loss of blood in the stool, or dark or black stools Seizures or unexplained, small strokes (from bleeding into the brain) Shortness[nlm.nih.gov]
  • A person with abnormal GI tract blood vessels should watch for black stools and chronic anaemia that can cause fatigue, paleness, shortness of breath, chest pain or light-headedness.[cirse.org]
  • This procedure will typically only be undertaken if there is anemia that is more marked than expected by the severity of nosebleeds, or if there is evidence of severe bleeding (vomiting blood, black stools).[en.wikipedia.org]
Blood in Stool
  • These AVMs can weaken and rupture, causing bleeding into the lung (coughing up blood), gastrointestinal tract (vomiting blood, or blood in stool) and into the head (causing stroke).[sickkids.ca]
  • Gastrointestinal bleeding (blood in stool) may also develop, but is usually a later manifestation of the disease.[texaschildrens.org]
  • A patient may begin to cough up blood or pass blood in stools. The skin changes begin at puberty, and the condition becomes progressively worse until about 40 years of age, when it stabilizes.[healthofchildren.com]
  • Annual testing for occult blood in stool. Annual complete blood count to detect new-onset anemia, and more frequent testing based on the patient’s bleeding history.[cmaj.ca]
  • This procedure will typically only be undertaken if there is anemia that is more marked than expected by the severity of nosebleeds, or if there is evidence of severe bleeding (vomiting blood, black stools).[en.wikipedia.org]
Abdominal Pain
  • pain Leg swelling Anemia Artery malformations, which may affect pulmonary (lung) or cerebral (brain) circulation Screening for HHT The HHT Foundation recommends that all individuals diagnosed or suspected of having HHT undergo a thorough screening and[health.ucsd.edu]
  • Among them, headache (52 events), nausea and vomiting (12 events), asthenia (9 events), abdominal pain (4 events), muscular pain (4 events), diarrhea (6 events), and rash (1 event) were reported.[doi.org]
  • Shunting of blood from the hepatic artery to veins causes steal syndromes with abdominal pain from either biliary or mesenteric ischaemia 41 – 43.[doi.org]
Hematemesis
  • Case 1 : A 46-year-old man has had tendency to epistaxis, telangiectasia, hematemesis and bloody feces, iron-deficiency anemia, at the age of 12, 41, 46 respectively.[webview.isho.jp]
  • ., granulomatosis with polyangiitis, Goodpasture’s disease), lung trauma, pulmonary embolus, cardiac causes (mitral stenosis, left ventricular failure), and spurious (epistaxis, hematemesis).[clinicaladvisor.com]
Jaundice
  • Evaluations of her jaundice revealed chronic parenchymal liver disease with multiple nodules in the liver with early portal hypertension.[ncbi.nlm.nih.gov]
  • Liver AVMs may be suspected because of abnormal liver function tests in the blood, because the symptoms of heart failure develop, or because of jaundice or other symptoms of liver dysfunction.[en.wikipedia.org]
Vascular Disease
  • Hereditary hemorrhagic telangiectasia (HHT), an autosomal dominant vascular disease, involves mainly skin, mucocutaneous membranes, and viscera.[ncbi.nlm.nih.gov]
  • Expert reviewer(s): VASCERN-HHT (EUROPEAN REFERENCE NETWORK FOR VASCULAR DISEASES) - Last update: January 2019 The documents contained in this web site are presented for information purposes only.[orpha.net]
  • Much of what is known about pulmonary vascular disease is from clinical research conducted right here.[uchealth.org]
  • Cummings and Sanjeev Bhalla, Pulmonary Vascular Diseases, Clinics in Chest Medicine, 10.1016/j.ccm.2015.02.007, 36, 2, (235-248), (2015).[doi.org]
  • Hereditary haemorrhagic telangiectasia (HHT) is a single, relatively common “Rare” Vascular Disease with distinct screening and management recommendations.[vascern.eu]
Chest Pain
  • A person with abnormal GI tract blood vessels should watch for black stools and chronic anaemia that can cause fatigue, paleness, shortness of breath, chest pain or light-headedness.[cirse.org]
  • The most common post-procedural complication is self-limited pleuritic chest pain in 10-30% of cases.[clinicaladvisor.com]
  • The most common complication of embolisation is pleuritic chest pain 18, 19, 36, which is most often self-limited. There is a 18, 19, 36, with distal complications occurring only very rarely.[doi.org]
Epistaxis
  • No drug treatment was significantly different from placebo for epistaxis duration. All groups had a significant improvement in Epistaxis Severity Score at weeks 12 and 24.[ncbi.nlm.nih.gov]
  • The Epistaxis Severity Score (ESS) was used to evaluate the treatment effects. Patients reported that epistaxis improved 1 to 3 weeks after starting thalidomide.[ncbi.nlm.nih.gov]
  • Treatment of HHT-related epistaxis presents a challenge to the otolaryngologist due to the recurrent, persistent nature of epistaxis often requiring multiple treatments.[ncbi.nlm.nih.gov]
  • After six months follow-up, there was no epistaxis recurrence. Various treatments for epistaxis in this disease have been described in the literature, but there is no consensus about the gold-standard procedure.[ncbi.nlm.nih.gov]
  • Overall, the present study confirms the positive influence of tNO on epistaxis in HHT patients and on subjective satisfaction.[ncbi.nlm.nih.gov]
Spontaneous Recurrent Epistaxis
  • Patients with suspicion of HHT based on clinical data, such as: 1) spontaneous recurrent epistaxis, 2) cutaneous telangiectasia, 3) visceral lesions (arteriovenous malformations), and/or 4) first-degree relatives with those characteristics.[admerahealth.com]
  • The Curaçao Criteria for the diagnosis of HHT include: (1) spontaneous, recurrent epistaxis, (2) telangiectasias at the nose, lips, oral cavity, and fingertips, (3) visceral lesions such as gastrointestinal telangiectasias or AVMs in the pulmonary, hepatic[omicsonline.org]
  • Larger visceral arteriovenous malformations (AVMs) can be found in the brain, lung, liver, and elsewhere. 3 The clinical diagnosis of HHT is based on the presence of at least 3 of the following criteria: spontaneous recurrent epistaxis, multiple characteristic[phaonlineuniv.org]
  • If three or four are met, a patient has "definite HHT", while two gives "possible HHT": Spontaneous recurrent epistaxis Multiple telangiectasias in typical locations (see above) Proven visceral AVM (lung, liver, brain, spine) First-degree family member[en.wikipedia.org]
Confusion
  • The signs of a stroke are: Sudden numbness or weakness of the face, arm or leg, especially on one side of the body Sudden confusion Sudden trouble speaking Sudden trouble seeing in one or both eyes Sudden trouble walking Sudden dizziness, loss of balance[cedars-sinai.edu]
  • To make things even more confusing, these symptoms are often seen in HHT patients as side effects of other health problems including heart failure, anemia and liver problems.[phassociation.org]
  • If the flow in the AVM is in the other direction, portal venous blood flows directly into the veins rather than running through the liver; this may lead to hepatic encephalopathy (confusion due to portal waste products irritating the brain).[en.wikipedia.org]
  • This is not the case for nosebleeds, which are common in the general population, or non-florid telangiectasia, which can be readily confused with non-HHT pathologies.[doi.org]
  • Portal vein to hepatic vein shunts predispose to hepatic encephalopathy manifested by confusion and asterixis 41, 42.[doi.org]

Workup

HHT can be diagnosed with genetic testing, but it is important to note that not all mutations involved in the disease have been identified. Family members of the patient in question should also be tested if the test is positive. On the other hand, a negative genetic test precludes from screening for manifestations and complications of HHT. This can be reassuring for parents, especially since the screening procedures may require anesthesia or the administration of sedatives. Children of parents diagnosed with HHT are considered to have the disease for screening purposes, unless genetic testing is explicitly negative [15].

Screening for HHT complications is mostly targeted at systemic pulmonary, cardiovascular and neurological manifestations. Contrast transthoracic echocardiography is the most important test used to detect AVMs in the lungs. Children who are too young to undergo the procedure may have their oxygen saturation rate measured with a pulse oximeter. A negative screening result on transthoracic echocardiography necessitates the repetition of the procedures every three to five years to detect any new lesions. MRI, on the other hand, is utilized to screen for the presence of AVMs in the brain. Adults undergo a specific MRI protocol to maximize sensitivity. It involves MRI with and without contrast, in addition to sequences that detect blood products. Children who are diagnosed or suspected to have HHT require a non-contrast MRI in the first 6 months of life. Positive findings necessitate referral to specialized neurovascular centers for possible invasive testing and treatment. Negative test results do not require the repetition of the MRI, although some experts recommend an MRI later in adulthood [16].

Finally, screening for gastrointestinal or liver lesions should only be made in the presence of bleeding, anemia of unknown cause, heart or liver failure.

Polyps
  • The patient was found to have polyps on colonoscopy leading to genetic testing revealing an SMAD4 mutation.[ncbi.nlm.nih.gov]
  • Hereditary hemorrhagic telangiectasia types 1, 2 and 3 do not appear to increase the likelihood of such polyps.[ghr.nlm.nih.gov]
  • SMAD4, which causes a combined syndrome of juvenile polyposis (multiple polyps in the intestine) and HHT. The mutated gene copy encodes a protein that is unable to perform its intended function in the cell.[upmc.com]
  • Multiple genes have been identified as having involvement in this disease, including a gene that also causes polyps in the colon or, potentially, colon cancer.[uchospitals.edu]
  • The fourth mutation that was identified is present in the SMAD4 gene and, in addition to HHT, it is associated with juvenile polyposis, a condition characterized by abnormal polyp growth in the gastrointestinal tract.[symptoma.com]

Treatment

Treatment for HHT is generally supportive, although accessible telangiectatic lesions in the nose or in the gastrointestinal tract may be targeted with laser ablation [17]. Surgical resection or embolization can also be used to remove characteristic arteriovenous fistulas present in the disorder [18].

Patients require hepatitis B immunization because of frequent blood transfusions. Significant blood loss also necessitates iron supplementation, sometimes parenteral, on top of erythropoietin therapy. Aminocaproic acid and tranexamic acid can also be used to inhibit fibrinolysis.

Prognosis

With aggressive and adequate treatment and screening, the prognosis of HHT is good, with the life expectancy of patients approaching that of the healthy population. On average, however, HHT shortens life expectancy with peaks of mortality occurring at 50 years of age and 60-79 years. The second peak is mostly related to the acute complications of the disease [12]. Prognosis also depends on the extent and severity of the systemic involvement particularly in regards to the pulmonary system, liver and nervous system. Overall, complications of HHT result in the death of only 10% of patients.

Etiology

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disease transmitted in an autosomal dominant fashion; Cases involving spontaneous mutations have been also described [3]. Around 600 mutations are involved in the 4 genes associated with the disease, although a single family will usually share the same mutation.

Because it an autosomal dominant trait, the risk of transmission from a carrier parent to a child is around 50%, irrespective of the gender of the child. Normally, each individual possesses two copies from every gene, and a single copy of a dominant gene can be sufficient to drive phenotypic expression.

Four genes have been linked to HHT. One gene, called ENG, encodes for a protein called endoglin and is expressed on the membrane of endothelial cells. Scientists have shown that endoglin binds to the transforming growth factor beta (TGF-ß) and is critical to the normal development of blood vessels. Indeed, deficiencies in endoglin result in failure of blood vessel maturation and smooth muscle development [4]. 

On the other hand, mutations in the activin receptor-like kinase 1 (ACVRL1) are more strongly associated with liver arteriovenous malformations, as well as increased blood pressure in the pulmonary circulation (pulmonary hypertension) [5]. The latter is also associated with mutations in the BMPR9 gene, which can cause characteristic vascular abnormalities present in HHT too. The fourth mutation that was identified is present in the SMAD4 gene and, in addition to HHT, it is associated with juvenile polyposis, a condition characterized by abnormal polyp growth in the gastrointestinal tract. 

All of these genes have been linked to the TGF-ß/BMP (bone morphogenic protein) complex. This group of signaling molecules is associated with cellular growth, differentiation and survival. Abnormalities therein underlie problems in angiogenesis and result in the characteristic features of HHT.

Epidemiology

HHT remains a very rare disease in the United States, with its incidence reported to be 1-2 cases per 100,000 individuals and prevalence around 1-2 cases in 10,000 individuals. The disease, however, may be much more common, since many patients have a mild asymptomatic form. For example, overall prevalence of HHT in Vermont is estimated to be 1 case in every 16,400 individuals [6]. 

HHT is much more common internationally, particularly in Europe and Japan, where it is estimated to be present in 1 out of 5000 to 8000 individuals [7]. In Denmark, prevalence has increased from 13.8 to 15.6 cases in 100,000 individuals, across a 21-year time range from 1974 to 1995 [8].

HHT is an autosomal dominant disease with a penetrance of 97%.

Sex distribution
Age distribution

Pathophysiology

Hereditary hemorrhagic telangiectasia is characterized by several abnormalities in vascular structure and function including telangiectasia, arteriovenous malformations and aneurysms. The pathophysiological mechanisms thought to underlie the disease are caused by a dysfunction in the transforming growth factor ß (TGF-ß) signaling complex, resulting in impaired endothelial growth and differentiation. Despite strong genetic links, ultrastructural imaging demonstrates normal vessel architecture in some areas, leading some researchers to propose that lesions are caused by an environmental trigger followed by impaired growth and repair [9]. 

Telangiectasias are dilated capillaries and postcapillary venules that are found most commonly in the retina, the gastrointestinal tract, mucous membranes, and conjunctiva. They result from weak perivascular connective tissue as well as disrupted endothelial junctions and degeneration. Arteriovenous malformations (AVMs), on the other hand, are tortuous veins and arteries that can result in left to right shunting and potential high-output heart failure. Aneurysms are caused by a loss of elasticity and muscular layers within the vessels and can be present in the liver, brain and lungs.

Several genes are involved in the pathogenesis of HHT and they generally affect processes related to angiogenesis, cell migration and proliferation, integrity of the cellular skeleton and nitric oxide synthesis [10]. The majority of the genes responsible for telangiectasias and AVM bleeding are related to TGF-ß signaling and interactions. The most common mutations affect the endoglin and ALK-1 genes, which code for TGF-ß Type III and type I receptors respectively.

Endoglin promotes the binding of TGF-ß to type II TGF-ß receptors, ultimately resulting in the phosphorylation of ALK-5 and ALK-1, both type I TGF-ß receptors. These in turn activate Smad 2/3 and Smad 1/5, downstream proteins that dissociate from the TGF-ß receptors and exert their effects by binding to Smad 4. The bound Smad 4 protein can enter the nucleus and regulate the transcription of genes critical to angiogenesis. It is a delicate balance between ALK-5 and ALK-1 signaling pathways that ultimately shapes the characteristics of the endothelium in angiogenesis [11].

On a histopathological examination, blood vessels are characterized by thin, large and irregular walls but the damage is not equally expressed among individuals with HHT. Patients with O type blood seem to be affected more frequently, and there are no differences between men and women. The exact pathological mechanisms underlying these differences are still not well understood. Bleeding may also be related to coagulopathies and an elevated rate of fibrinolysis.

Prevention

There are no known preventive measures for HHT.

Summary

Hereditary hemorrhagic telangiectasia (HHT) is a rare genetic disease characterized by the formation of telangiectasias and arteriovenous malformations [1]. It is transmitted in an autosomal dominant fashion, although expression is not uniform. HHT is thought to be more common in individuals with an O blood type, but is equally prevalent in men and women.

Mutations in several genes involved in angiogenesis are thought to underlie the disease. They usually affect TGF-ß signaling, a molecule critical for cellular growth and differentiation. Defects in the TGF-ß pathway ultimately result in abnormal gene expression and vessel formation.

HHT most commonly presents with telangiectatic lesions on the face, oral and nasal mucosa, in the lungs, brain and gastrointestinal tract [2]. Patients can suffer from recurrent nosebleeds and gastrointestinal hemorrhage. More severe forms of the disease can present acutely with strokes, transient ischemic attacks or brain abscesses.

Diagnosis is established with testing for genetic mutations, although not all genes responsible for the disease have been identified. Patients with a positive testing result require screening for other systemic manifestations, particularly with an MRI of the brain or a transthoracic echocardiography to detect lesions in the lungs.

Treatment is mostly supportive. Patients may require frequent blood transfusions and iron supplementation. Lesions can be removed with laser therapy, embolization or surgery.

Patient Information

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disease that targets the blood vessels and results in their abnormal development, structure and function. It is characterized by vessels with weak walls, as well as an absence of capillaries in some cases, the tiny vessels that are normally present between the arteries and the veins. HHT is transmitted in an autosomal dominant fashion. This entails that having one copy of the abnormal gene is sufficient to develop the disease. A child with an affected parent has a 50% chance of acquiring HHT.

HHT is caused by abnormal development and proliferation of endothelial cells, the cells that line the blood vessels. Several genetic mutations are thought to be involved, although four are most common. They ultimately result in abnormal communication between cells, largely due to defects in the signaling pathway of a molecule called TGF-ß.

Patients with HHT usually present with lesions of their capillaries on their face, in their nose or on the inside of their mouth. In some cases, lesions may also occur in the gastrointestinal tract, lungs and brain. Patients with HHT have an increased tendency to bleed and recurrent nosebleeds or gastrointestinal hemorrhage are not uncommon. More severe forms can also be distinguished. They involve lesions in the lungs, brain and liver and may lead to strokes, liver failure or heart failure.

HHT can be diagnosed with tests that detect abnormal genes. All family members of diagnosed patients need to be tested. Positive tests usually indicate a requirement to perform several screening procedures, to check for the presence of any of the severe systemic manifestations of HHT. These tests can involve sedation or anesthesia, which can be disconcerting for parents. Important screening tests are required to identify any lesions in the lungs and in the brain. In case the results return positive, the patients may need to be transferred to specialized centers for invasive diagnosis and treatment.

Treatment for HHT is mostly supportive although some lesions that are deemed accessible can be removed with laser ablation, embolisation or surgery. Patients may frequently require blood transfusions because of bleeding, so it is important for them to receive hepatitis B immunization. Blood loss can also necessitate supplementation with iron and a hormone called erythropoeitin.

HHT has a good prognosis if the patients are aggressively and adequately treated and screened. Overall, however, patients tend to have a shorter life expectancy. Mortality occurs at two peaks around 50 years of age and 60 - 79 years of age. The latter peak is due to acute complications.

There are no known preventive measures for HHT.

References

Article

  1. Giordano P, Lenato GM, Suppressa P, et al. Hereditary hemorrhagic telangiectasia: arteriovenous malformations in children. J Pediatr. 2013 Jul; 163(1):179-86.e1-3.
  2. Lacombe P, Lagrange C, Beauchet A, et al. Diffuse pulmonary arteriovenous malformations in hereditary hemorrhagic telangiectasia: long-term results of embolization according to the extent of lung involvement. Chest. 2009 Apr; 135(4):1031-7.
  3. Grover S, Grewal RS, Verma R, et al. Osler-Weber-Rendu syndrome: a case report with familial clustering. Indian J Dermatol Venereol Leprol. 2009 Jan-Feb; 75(1):100-1.
  4. McAllister KA, Grogg KM, Johnson DW, et al. Endoglin, a TGF-beta binding protein of endothelial cells, is the gene for hereditary haemorrhagic telangiectasia type 1. Nat Genet. 1994 Dec; 8(4):345-51.
  5. Johnson DW, Berg JN, Baldwin MA, et al. Mutations in the activin receptor-like kinase 1 gene in hereditary haemorrhagic telangiectasia type 2. Nat Genet. 1996 Jun; 13(2):189-95.
  6. Guttmacher AE, Marchuk DA, White RI Jr. Hereditary hemorrhagic telangiectasia. N Engl J Med. 1995 Oct 5; 333(14):918-24.
  7. Franchini M, Frattini F, Crestani S, et al. Novel treatments for epistaxis in hereditary hemorrhagic telangiectasia: a systematic review of the clinical experience with thalidomide. J Thromb Thrombolysis. 2013 Oct; 36(3):355-7.
  8. Kjeldsen AD, Vase P, Green A. Hereditary haemorrhagic telangiectasia: a population-based study of prevalence and mortality in Danish patients. J Intern Med. 1999 Jan; 245(1):31-9.
  9. van Laake LW, van den Driesche S, Post S, et al. Endoglin has a crucial role in blood cell-mediated vascular repair. Circulation. 2006 Nov 21; 114(21):2288-97.
  10. Fernandez-L A, Garrido-Martin EM, Sanz-Rodriguez F, et al. Gene expression fingerprinting for human hereditary hemorrhagic telangiectasia. Hum Mol Genet. 2007 Jul 1; 16(13):1515-33.
  11. Shovlin CL, Hughes JM, Scott J,et al. Characterization of endoglin and identification of novel mutations in hereditary hemorrhagic telangiectasia. Am J Hum Genet. 1997 Jul; 61(1):68-79.
  12. Kjeldsen AD, Oxhøj H, Andersen PE, et al. Pulmonary arteriovenous malformations: screening procedures and pulmonary angiography in patients with hereditary hemorrhagic telangiectasia. Chest. 1999 Aug; 116(2):432-9.
  13. Cottin V, Dupuis-Girod S, Lesca G, et al. Pulmonary vascular manifestations of hereditary hemorrhagic telangiectasia (rendu-osler disease). Respiration 2007; 74:361–378.
  14. Garcia-Tsao G, Korzenik JR, Young L, et al. Liver disease in patients with hereditary hemorrhagic telangiectasia. N Engl J Med 2000; 343:931–936.
  15. Giordano P, Nigro A, Lenato GM, et al. Screening for children from families with Rendu-Osler-Weber disease: from geneticist to clinician. J Thromb Haemost. 2006; 4(6):1237–1245.
  16. Schneider G, Uder M, Koehler M, et al. MR angiography for detection of pulmonary arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia. AJR Am J Roentgenol. 2008 Apr; 190(4):892-901.
  17. Harries PG, Brockbank MJ, Shakespeare PG, et al. Treatment of hereditary haemorrhagic telangiectasia by the pulsed dye laser. J Laryngol Otol. 1997 Nov; 111(11):1038-41.
  18. Layton KF, Kallmes DF, Gray LA, et al. Endovascular treatment of epistaxis in patients with hereditary hemorrhagic telangiectasia. AJNR Am J Neuroradiol. 2007 May; 28(5):885-8.

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Last updated: 2019-07-11 19:59