Liver transplantation as definitive therapy for complications after arterial embolization for hepatic manifestations of hereditary hemorrhagic telangiectasia

Perioperative Complications and Long-Term Follow-Up of Liver Transplantation in Hemorrhagic Hereditary Telangiectasia: Report of Three Cases and Systematic Review

The aim was to describe three patients with hemorrhagic hereditary telangiectasia (HHT) requiring liver transplantation (LT) and to perform a systematic review focusing on surgical complications and long-term follow-up. Unrestricted searches of the Medline and Embase databases were performed through February 2022. Forty-five studies were selected including 80 patients plus the three new reported patients, 68 (81.9%) were female and mean age was 50 (27–72) years. Main indications for LT were high-output cardiac failure (n = 40; 48.2%), ischemic cholangitis (n = 19; 22.9%), and a combination of both conditions (n = 13;15.6%). Mean cold ischemic time and red blood cell units transfused during LT were 554 (300–941) minutes and 11.4 (0–88) units, respectively. Complications within 30 days were described in 28 (33.7%) patients, mainly bleeding complications in 13 patients, hepatic artery (HA) thrombosis in four and hepatic vein thrombosis in one. Mean follow-up was 76.4 (1–288) months, and during it, four new patients developed thrombotic complications in HA, HA aneurysm, celiac artery, and the portal–splenic–mesenteric vein. HHT relapse in the transplant allograft was detected in 13 (17.1%) patients after 1–19 years (including two fatal recurrences). Overall mortality was 12%. In conclusion, previous assessment of HA anatomy and hyperdynamic circulatory state could reduce LT complications. The risk of relapse in the hepatic graft supports a multidisciplinary follow-up for HHT patients with LT.

Preoperative arterial embolization of large liver hemangiomas

PURPOSE

We aimed to investigate the efficacy and safety of preoperative selective intra-arterial embolization (PSIAE) in the surgical treatment of large liver hemangiomas.

METHODS

Data of 22 patients who underwent resection of large liver hemangiomas were retrospectively analyzed. PSIAE was performed in cases having a high risk of severe blood loss during surgery (n=11), while it was not applied in cases with a low risk of blood loss (n=11).

RESULTS

A total of 19 enucleations and six anatomic resections were performed. Operative time, intraoperative bleeding amount, Pringle period, and blood transfusion were comparable between the two groups (P > 0.05, for all). The perioperative serum aspartate transaminase level was not different between groups (P = 1.000). Perioperative total bilirubin levels were significantly increased in the PSIAE group (P = 0.041). Postoperative hospital stay was longer in the PSIAE group. Surgical complications were comparable between groups (P = 0.476).

CONCLUSION

Patients who underwent PSIAE due to a high risk of severe blood loss during resection of large liver hemangiomas had comparable operative success as patients with a low risk of blood loss who were operated without PSIAE. Hence, PSIAE can be used for the control of intraoperative blood loss, especially in surgically difficult cases.

Complications and clinical outcome of hepatic artery embolisation in patients with hereditary haemorrhagic telangiectasia

BACKGROUND

Hepatic artery embolisation (HAE) in patients with hereditary haemorrhagic telangiectasia (HHT) is controversial because of the associated complications and unproven long-term benefit. We present our results in 20 such patients over a time span of 17 years.

METHODS

Staged HAE was performed using polyvinyl alcohol (PVA) particles and coils. Complications, clinical symptoms and cardiac output were assessed before and after therapy as well as at the end of follow-up (median 92 months, range 26-208 months).

RESULTS

Two patients died within 30 days following HAE (10 %). Four further deaths resulted from causes unrelated to HAE. Ischaemic cholangitis, cholecystitis and focal hepatic necrosis with biliary sepsis necessitated re-intervention in four patients. In all but one patient, clinical symptoms resolved with mean cardiac output falling from 11.84 ± 3.22 l/min pre-treatment to 8.13 ± 2.67 l/min at the end of follow-up (P < 0.001). One patient required liver transplantation for de novo symptoms of portal hypertension 4 years after primary symptoms had been cured by HAE.

CONCLUSION

The 30-day mortality of HAE in patients with HHT is 10 %. The rate of complications requiring re-intervention is 20 %. Clinical response at long-term follow-up is satisfactory.

Successful liver transplantation for Rendu-Weber-Osler disease, a single centre experience

BACKROUNDS/PURPOSE: Hereditary hemorrhagic telangiectasia or Rendu-Weber-Osler is an autosomal dominant inherited disorder characterized by arteriovenous malformations and telangiectasia that may affect the nose, skin, lungs, brain and gastrointestinal tract. Liver involvement of the disease has been described to be responsible of biliary tract necrosis, high cardiac output and portal hypertension, due to intra-hepatic vascular shunts. We aimed to present four cases of successful orthotopic liver transplantations in this indication performing our modified Piggy-back technique.

PATIENTS AND METHODS

Between 2002 and 2008, four patients have been diagnosed for Rendu-Weber-Osler disease and underwent liver transplantation. Three of them suffered from high cardiac output with heart failure, two presented HBV infection and one patient suffered from renal failure requiring a liver-kidney transplantation. We performed our modified Piggy-back technique for liver implantation, which consists to clamp selectively the hepatic veins during the hepatectomy, without venous bypass, the retro-hepatic vena cava is preserved.

RESULTS

No hemodynamic concerns disturbed the surgery and no massive transfusions were needed. The liver replacement corrected the cardiac insufficiency due to high cardiac output for the three patients. At present, the four patients are getting well.

CONCLUSIONS

Despite new advances in immunotherapy for the medical treatment of Rendu-Weber-Osler disease, liver transplantation remains the curative option for hepatic based-hereditary hemorrhagic telangiectasia.

Review article: the hepatic manifestations of hereditary haemorrhagic telangiectasia

BACKGROUND

Liver involvement in hereditary haemorrhagic telangiectasia is mainly characterized by vascular malformations, such as telangiectasies and arteriovenous shunts, which are found in up to 80% of patients.

AIM

To analyse the current knowledge and controversies regarding the epidemiological, pathological, clinical, diagnostic and therapeutic aspects of liver involvement in hereditary haemorrhagic telangiectasia. Methods Systematic survey analysis of the indexed studies dealing with the above mentioned topics.

RESULTS

No more than 8% of patients with hepatic vascular abnormalities will have a symptomatic liver disease, mainly consisting in high-output heart failure, portal hypertension or biliary disease.

CONCLUSIONS

Colour Doppler ultrasonography is a non-invasive, highly accurate and relatively low-cost procedure for the screening of liver involvement in patients with hereditary haemorrhagic telangiectasia; computed tomography, magnetic resonance imaging and angiography can be reserved for the characterization of focal lesions and the study of severely ill patients in whom invasive therapeutic procedures are advisable. Patients with asymptomatic liver involvement should not receive any treatment, while the therapeutic options for symptomatic patients include treatment of the specific complication, invasive procedures for shunt reduction and liver transplantation. The newly developed antiangiogenetic therapies appear to be very promising, but still require further evaluation in clinical trials.

Treatment of high output cardiac failure by flow-adapted hepatic artery banding (FHAB) in patients with hereditary hemorrhagic telangiectasia

Involvement of abdominal organs in Osler's disease may lead to the development of hepatic arteriovenous shunts with a dilatation of the hepatic artery. Right and subsequent global heart failure due to cardiac valvular insufficiency, pulmonary artery hypertension, and hepatomegaly as well as increased cardiac output may result. This hyperdynamic hepatic blood flow can be reduced by ligature or banding of the hepatic artery or by orthotopic liver transplantation. We report on two female patients suffering from Osler's disease (68 and 76 years old) with severe heart insufficiency (NYHA III-IV) caused by the high hepatic shunt volumes. A gradual banding of the hepatic artery directed by intraoperative flow measurement in the hepatic artery and control of the systemic hemodynamics by Swan-Ganz or COLD catheters was performed in these patients. The banding was achieved by encasing the hepatic artery in a PTFE cuff (length, 1.0 cm). The high cardiac output could be reduced from 11.2 to 7.0 l/min and from 10.7 to 6.0 l/min, respectively. The respective hepatic artery flow was reduced from 2.0 to 0.3 l/min and from 4.0 to 0.7 l/min. An improvement of heart insufficiency, a reduction in the severity of the cardiac valvular insufficiency, and a reduction of the pulmonary arterial hypertension could be already observed intraoperatively. One patient died of right cardiac failure after an orthotopic liver transplantation 7 months later. The other one died 3 years after the banding. The banding of the hepatic artery controlled by hepatic arterial flow measurement can be considered as an effective and safe palliative procedure in intrahepatic HHT compared to therapeutic alternatives such as hepatic artery ligation or embolization.

Rupture of hepatic aneurysm complicating hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu disease) for which hepatic arterial coil embolization was effective

A 74-year-old woman was transferred to our hospital for further examinations because of abdominal fullness and abnormal levels of serum liver/biliary enzyme persisting for 3 weeks. She had anemia and dilatation of many capillary vessels in her fingers, palms, and tongue in addition to reporting frequent incidences of nasal bleeding in herself and her family. Abdominal ultrasonography detected a cystic lesion in the right hepatic lobe, connected to a dilated tortuous hepatic artery. A low-echoic hepatic phyma was also detected in the back of the cystic lesion. Abdominal computed tomography and magnetic resonance imaging indicated that the cystic lesion was an aneurysm and the low-echoic phyma was a hematoma. Hepatic arteriography confirmed a hepatic aneurysm, tortuous dilatation of the hepatic artery, and the complication of an arteriovenous shunt in the liver. Taking all of these findings into consideration, this case was diagnosed as hereditary hemorrhagic telangiectasia (HTT) complicated by a hepatic aneurysm causing intrahepatic hematoma. To prevent re-rupture of the aneurysm, we performed a hepatic arterial coil embolization. After therapy, no blood flow to the aneurysm was detected by ultrasonic color Doppler method and the hematoma gradually diminished. There have been no reports of a case in which hepatic arterial embolization was effective for HHT-associated hepatic aneurysm causing intrahepatic hematoma. This very rare case provides important clinical information regarding abdominal vascular complications of HTT and a less invasive treatment for them.

The Role of Liver Transplantation in the Treatment of Hereditary Hemorrhagic Telangiectasia: A Short Literature Review

The liver is involved in up to 73% of patients suffering from hereditary hemorrhagic telangiectasia (HHT), but only some of them become symptomatic. Although management is often conservative, sometimes a more aggressive approach is required. The role of surgery is still undefined. Open ligation, banding, or closure of the arteriovenous malformation feeding artery have been proposed but rejected, as they are followed by an unacceptably high incidence of complications, derived from ischemia of the biliary tree. Orthotopic liver transplantation (OLT) has been successfully attempted in 28 patients with cardiac, biliary, or portal hypertension as well as mixed clinical presentations. Twenty-four were alive at time of data collection. Cardiovascular and pulmonary functions have improved after the operation in most cases. Intrahepatic relapse of the hallmark lesion of the disease (telangiectasia and arterovenous malformation) has been recently described in two cases. OLT represents a valuable therapeutic option for hepatic-based HHT, provided early diagnosis and referral to a specialized unit.

Liver involvement in hereditary hemorrhagic telangiectasia (HHT)

Liver involvement in hereditary hemorrhagic telangiectasia (HHT) consists of extensive intrahepatic vascular malformations associated with blood shunting (arteriovenous, arterioportal and/or portovenous). It is a rare disorder that nevertheless can result in significant systemic and hepatobiliary abnormalities. Although hepatic vascular malformations are present in a majority of patients with HHT, symptoms occur in a only a minority with a clear predominance for the female gender. Symptoms from liver vascular malformations are often misdiagnosed and this can lead to potentially harmful interventions. In this review article, clinical findings of liver involvement in HHT and their pathophysiology are discussed as well as diagnostic methodologies, therapies used and their outcome. Data presented is based on a review of the literature performed in October 2006 using the following MEDLINE search terms: (hereditary hemorrhagic telangiectasia [ALL] OR Rendu-Osler-Weber [ALL]) AND (liver OR hepatic [ALL]). Papers were considered if they were published in English and if they included specific cases that were sufficiently described.

Liver transplantation for hereditary hemorrhagic telangiectasia: Report of the European liver transplant registry

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease is a rare disease characterized by the presence of arteriovenous malformations. Hepatic involvement can lead to life-threatening conditions.

MATERIAL AND METHODS

Forty patients, reported to the European Liver Transplant Registry, were analyzed to define the role of liver transplantation in the treatment of the hepatic disease form. Indications for transplantation were classified according to Garcia-Tsao: cardiac failure (14 patients), biliary necrosis causing hepatic failure (12 patients), severe portal hypertension (5 patients), cardiac failure and biliary necrosis (6 patients), cardiac failure and portal hypertension (2 patients), and cardiac failure associated with biliary necrosis and portal hypertension (1 patient). Eighteen (81%) of 22 patients had pulmonary artery hypertension. Twelve (30%) patients had pretransplant hepatic interventions. Follow-up was complete for all patients with a mean of 69 months (range, 0-230 months).

RESULTS

One-, 5- and 10-year actuarial patient and graft survival rates are 82.5%. Six of the 7 pretransplant procedures performed on the hepatic artery were severely complicated. Cardiovascular function documented in 24 patients improved in 18 patients and remained stable in 5 patients; 1 patient died perioperatively of acute heart failure. Twenty-four (60%) patients had post-transplant complications, all but one occurring within the first 4 posttransplant months. Seven (17.5%) patients died perioperatively, 6 of them due to bleeding and 1 due to cardiac failure; 1 (2.5%) patient died late due to chronic rejection. There were 2 possible recurrences. Quality of life markedly improved in all 32 surviving patients.

CONCLUSION

The results of the largest reported transplant series in the treatment of hepatic-based HHT are excellent. Elimination of hepatobiliary sepsis and reversal of cardiopulmonary changes dramatically improve quality of life of the recipients. LT should be proposed earlier in the course of symptomatic hepatic HHT presenting with life-threatening conditions. Palliative interventions, especially on the hepatic artery, should be avoided in view of their high (infectious) complication rate.

Liver transplantation for cardiac failure in patients with hereditary hemorrhagic telangiectasia

Liver involvement in hereditary hemorrhagic telangiectasia may lead to high-output cardiac failure. Few data have been reported on orthotopic liver transplantation (OLT) for these patients. In this paper, we describe two patients treated by OLT as a salvage procedure for cardiac failure, and we review literature on this subject. Our two patients resumed normal cardiac function after OLT. This procedure appears to be a promising therapy with good long-term results despite dissection difficulties encountered due to the collateral arterial network reorganization.

Hereditary hemorrhagic telangiectasia: an overview of diagnosis and management in the molecular era for clinicians

Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome) is a relatively common, underdiagnosed autosomal-dominant disorder of arteriovenous malformations and telangiectases. DNA testing for hereditary hemorrhagic telangiectasia has recently become available in North America, making presymptomatic screening available to relatives with a positive molecular diagnosis. This now enables practitioners to prevent catastrophic complications of undiagnosed pulmonary and CNS arteriovenous malformations and eliminates the need to radiographically screen all at-risk relatives shown to be unaffected by molecular testing. We review the clinical aspects of hereditary hemorrhagic telangiectasia, describe the indications, benefits, and limitations of molecular diagnostic testing for hereditary hemorrhagic telangiectasia, and provide a molecular genetics summary to facilitate genetic counseling before and after DNA testing for this complex disorder.

Hepatic artery embolization for treatment of patients with hereditary hemorrhagic telangiectasia and symptomatic hepatic vascular malformations

At present there is no established therapy for treating patients with hereditary hemorrhagic telangiectasia (HHT) and symptomatic hepatic involvement. We present the results of a prospective study with 15 consecutive patients who were treated with staged hepatic artery embolization (HAE). Branches of the hepatic artery were selectively catheterized and embolized in stages using polyvinyl alcohol particles (PVA) and platinum microcoils or steel macrocoils. Prophylactic antibiotics, analgesics and anti-emetics were administered after every embolization. Clinical symptomatology and cardiac output were assessed before and after therapy as well as at the end of follow-up (median 28 months; range 10-136 months). Five patients had abdominal pain and four patients had symptoms of portal hypertension. The cardiac output was raised in all patients, with cardiac failure being present in 11 patients. After treatment, pain resolved in all five patients, and portal hypertension improved in two of the four patients. The mean cardiac output decreased significantly ( P<0.001) from 12.57+/-3.27 l/min pre-treatment to 8.36+/-2.60 l/min at the end of follow-up. Symptoms arising from cardiac failure resolved or improved markedly in all but one patient. Cholangitis and/or cholecystitis occurred in three patients of whom two required a cholecystectomy. One patient with pre-existent hepatic cirrhosis died as a complication of the procedure. Staged HAE yields long-term relief of clinical symptoms in patients with HHT and hepatic involvement. Patients with pre-existing hepatic cirrhosis may be poor candidates for HAE.

Liver disease in hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu disease, is an hereditary disorder that results in fibrovascular dysplasia with the development of telangiectasias and arteriovenous malformations. It predominantly involves the skin, mucous membranes, viscera, lungs, and brain. Hereditary hemorrhagic telangiectasia shows great genetic heterogeneity, and its phenotypes have been classified based on the recently identified mutated genes: endoglin (HHT-1) and activin-like kinase receptor-1 (HHT-2). Other families with phenotypic HHT do not bear these mutations; therefore, other genes are probably involved as well. Liver involvement is reported in up to 30% of persons affected by HHT. Large arteriovenous malformations in the liver can lead to significant complications, including high-output congestive heart failure, portal hypertension, hepatic encephalopathy, biliary ischemia, and liver failure. Embolization of large arteriovenous malformations in the liver remains controversial; however, liver transplantation can successfully eradicate these complications.

Liver transplantation for treatment of intrahepatic Osler's disease: first experiences

BACKGROUND

Intrahepatic Osler's disease with multiple arteriovenous malformations and high intrahepatic shunting may lead to secondary pulmonary hypertension followed by right-heart stress and insufficiency. Until now, therapy with arterial embolization, banding, or ligation of the hepatic arteries is still limited and provides unsatisfactory long-term results. Liver transplantation offers another therapeutic option.

METHODS

We report on four patients with intrahepatic involvement of Osler's disease who were liver transplanted between 1995 and 1999. All patients suffered from restricted liver function and right-heart insufficiency with multiple cardiac decompensations. One patient received one course of embolization, and another received six courses of embolization and then banding of the main hepatic artery before transplantation. In both patients, the clinical symptoms improved for only a few months.

RESULTS

All patients had high degrees of intrahepatic arteriovenous shunting, and cardiac output measurements were between 8.0 to 13.3 L/min preoperatively. Preoperative mean pulmonary artery pressure was between 24 to 35 mmHg. After liver transplantation, cardiac output and right-heart diameter decreased or normalized and pulmonary pressure reached the normal range after 2 months. All patients received tacrolimus and steroids for primary immunosuppression. In one case, temporary hemodialysis was necessary for 2 weeks after transplantation, but renal function recovered completely. After follow-up time of 12 to 65 months, all patients had normal graft function and good cardiopulmonary condition.

CONCLUSIONS

Indication for liver transplantation should be considered in patients with intrahepatic Osler's disease, high arteriovenous shunting with right-heart stress, and restricted liver function before irreversible fixed pulmonary hypertension leads to severe right-heart insufficiency or failure. Our therapeutic regimen of early liver transplantation in the case of intrahepatic Osler's disease in four patients has promising results.

Liver disease in patients with hereditary hemorrhagic telangiectasia

BACKGROUND

Hereditary hemorrhagic telangiectasia, or Rendu-Osler-Weber disease, is an autosomal dominant disorder characterized by angiodysplastic lesions (telangiectases and arteriovenous malformations) that affect many organs. Liver involvement in patients with this disease has not been fully characterized.

METHODS

We studied the clinical findings and results of hemodynamic, angiographic, and imaging studies in 19 patients with hereditary hemorrhagic telangiectasia and symptomatic liver involvement.

RESULTS

We evaluated 14 women and 5 men who ranged in age from 34 to 74 years. All but one of the patients had a hyperdynamic circulation (cardiac index, 4.2 to 7.3 liters per minute per square meter of body-surface area). In eight patients, the clinical findings were consistent with the presence of high-output heart failure. The cardiac index and pulmonary-capillary wedge pressure were elevated in the six patients in whom these measurements were performed. After a median period of 24 months, the condition of three of the eight patients had improved, four were in stable condition with medical therapy, and one had died. Six patients had manifestations of portal hypertension such as ascites or variceal bleeding. The hepatic sinusoidal pressure was elevated in the four patients in whom it was measured. After a median period of 19 months, the condition of two of the six patients had improved, and the other four had died. Five patients had manifestations of biliary disease, such as an elevated alkaline phosphatase level and abnormalities on bile duct imaging. After a median period of 30 months, the condition of two of the five had improved, the condition of one was unchanged, heart failure had developed in one, and one had died after an unsuccessful attempt at liver transplantation.

CONCLUSIONS

In patients with hereditary hemorrhagic telangiectasia and symptomatic liver-involvement, the typical clinical presentations include high-output heart failure, portal hypertension, and biliary disease.

Portal-systemic encephalopathy in non-cirrhotic patients: classification of clinical types, diagnosis and treatment

Hepatic encephalopathy is suspected in non-cirrhotic cases of encephalopathy because the symptoms are accompanied by hyperammonaemia. However, the cause of the large portal-systemic shunt formation observed in these cases is not clear, as cirrhosis and portal hypertension are absent. The frequency of such cases reported in the literature is increasing with progress and spread of abdominal imaging diagnostic techniques. Some cases have been misdiagnosed as psychiatric diseases (dementia, depression and others) and consequently patients have been hospitalized in psychiatric institutions or geriatric facilities. Some paediatric cases have also been misdiagnosed. Therefore, the importance of accurate diagnosis of this disease should be strongly emphasized. Some paediatric cases have also been misdiagnosed. When psychoneurological symptoms are suggestive of hepatic encephalopathy but objective and subjective symptoms or abnormal values of liver function tests are not sufficiently indicative of liver cirrhosis, portal-systemic encephalopathy should be suspected. Abnormal angiograms of the portal vein, superior mesenteric vein or splenic vein are conclusive evidence of portal-systemic encephalopathy. Transrectal portal scintigraphy also provides information useful for detection of shunts and a quantitative estimation of shunt index. We classified the disease into five types based on whether the shunt is formed inside or outside the liver. Type I (intrahepatic type) designates cases in which shunts are located between the portal and systemic veins. Type II designates a type of intra/extrahepatic shunt that originates from the umbilical part of the portal vein and serpentines in the liver, then leaves the liver. Type III (extrahepatic type) occurs most frequently. Type IV (extrahepatic) is accompanied by shunts similar to those in type III, but hepatic pathology presents as idiopathic portal hypertension. Type V (extrahepatic) represents the congenital absence of the portal vein, where the superior mesenteric vein joins the intrahepatic inferior vena cava or the left renal vein. The prevalence of each type in our country was examined by a nationwide investigation. In addition to the conventional diet or drug treatments, obliteration by less invasive interventional radiology using a metallic coil and ethanol has recently been used more frequently than surgical occlusion of shunts. Shunt-preserving disconnection of portal and systemic circulation and partial splenic artery embolization are also performed. International investigation of the disease status and establishment of diagnostic and therapeutic methods for the disease are awaited and investigation of long-term prognosis after therapy is also necessary.

Clinical manifestations in a large hereditary hemorrhagic telangiectasia (HHT) type 2 kindred

HHT type 2 (HHT 2) is a multi-system vascular dysplasia caused by a mutation in the ALK-1 gene, but the phenotype has not been well defined. We report on 51 members of an HHT 2 kindred with an ALK-1 gene mutation shown to be associated with the disorder. This ALK-1 mutation was detected in 38 kindred members who were evaluated systematically for associated vascular abnormalities. Pulmonary arteriovenous malformations (AVMs) were found in 6% of those screened, cerebral AVM in 7%, hepatic AVM in 17%, and spinal AVM in 3%. We discuss these and other findings in the 38 affected kindred members, as well as findings in the 13 kindred members in whom the mutation was not detected. This study shows that pulmonary, cerebral, spinal, and hepatic AVMs can all occur in HHT 2. It also adds to the evidence suggesting that pulmonary AVMs are more common in HHT 1 than in HHT 2. We identify a higher prevalence of hepatic AVMs than previously reported in either HHT 1 or 2. This may be specific to the mutation in this kindred, but probably reflects the lack of routine screening for this manifestation. Even in this family in which all affected individuals have the same mutation, the clinical manifestations of HHT and their severity varied tremendously. Intrafamilial variation in expression of HHT is clearly significant, emphasizing the difficulty in establishing the diagnosis in individuals and in sub-typing families when DNA testing is not available.