What is Hereditary Hemorrhagic Telangiectasia?
Hereditary Hemorrhagic Telangiectasia (HHT, also known as Osler-Weber-Rendu Syndrome) is a complex disease involving malformed blood vessels that can impact multiple organ systems. HHT frequently goes undiagnosed and untreated, though it affects approximately 1 in 5,000 people. This inherited disorder affects both males and females of all ages and from all ethnic and racial backgrounds.
A variety of treatments exist for the various features of HHT to improve quality of life and prevent-life threatening complications. With appropriate treatment, individuals with HHT can expect a near-normal life expectancy.
The team of experts at UHealth has been named a HHT Center of Excellence by Cure HHT.
Here at the University of Miami Health System, we provide a multidisciplinary approach with several experienced HHT physicians and staff in the departments of interventional radiology, genetics, gastroenterology, neurosurgery, hematology, ENT, dermatology, pulmonology and cardiology. As a patient, you will meet and work directly with Dr. Joseph Zikria, M.D., the founding medical director of the University of Miami HHT Center, and his HHT Clinical Coordinator Shannon Lange, where patients will receive comprehensive care for the diagnosis and management of the condition to help improve their quality of life and overall health.
What causes HHT?
HHT is caused by an autosomal dominant genetic mutation. There are different mutations in each of the three genes known to cause HHT. This condition does not skip a generation, and each child born to an HHT parent has a 50% chance of inheriting the genetic mutation.
Symptoms of HHT
The symptoms associated with HHT vary from person to person. People with HHT tend to form arteriovenous malformations (AVMs), which are blood vessels that lack normal capillaries between an artery and vein. Some manifestations of HHT, such as telangiectasias (dilated small blood vessels or small AVMs) cause nosebleeds. Other complications (like larger AVMs in the lungs, brain or liver) may not necessarily trigger any initial symptoms and can happen at any age, but may cause serious and life-threatening complications.
The following symptoms or events can occur in people without HHT, but a family history could indicate you have HHT.
- Spontaneous nosebleeds (epistaxis): experienced by up to 90% of adults with HHT
- Iron deficiency anemia (low iron in the blood)
- Telangiectasias are red dots that disappear when pushed on. They can appear on the skin (including the lips, tongue, mouth, hands and face) and/or in the gastrointestinal tract (which can cause bleeding)
- Larger AVMs that develop in the brain, lungs and/or liver
- Life-threatening complications from lung AVMs or brain VMs
- Shortness of breath
- Exercise intolerance
- Migraine headaches
- Back pain, swelling or numbness
- Heart failure
How is HHT diagnosed?
The Curaçao Diagnostic Criteria for HHT
The Curaçao Diagnostic Criteria reflect the typical signs of HHT and consider your family history. If you have at least three of these criteria, you are diagnosed with HHT. If you have two of these criteria, you probably have HHT. If you experience only one of these criteria, it is unlikely that you have HHT.
These criteria are less reliable in diagnosing young children because some of these symptoms do not present until late childhood or adulthood.
- Recurrent and spontaneous mild to severe nosebleeds (epistaxis)
- Multiple telangiectasia on the hands, lips, face or inside of the nose or mouth
- AVMs or telangiectasia in the lungs, brain, liver, intestines, stomach and/or spinal cord
- Family history of HHT (i.e., a first-degree relative who experiences at least three of these criteria or has been genetically diagnosed with HHT)
Genetic testing for HHT
There are hundreds of potential mutations in each of the three genes known to cause HHT. The goal of genetic testing is to identify the specific HHT gene mutation that causes HHT within your family and confirm a HHT diagnosis. This information can be used to help diagnose other members of your family (often children and young adults) who do not meet the clinical diagnostic criteria. Genetic testing can identify asymptomatic (without symptoms) HHT or rule out HHT in children in families with a known mutation.
- A positive genetic test confirms that you carry your family’s HHT gene mutation and that you have HHT.
- A negative genetic test means that you do not carry your family’s HHT gene mutation, and you did not inherit HHT. However, a negative genetic test does not always rule out HHT.
- 15% of people with HHT have genetic mutations that are not yet identified as HHT genes. Repeat testing in the future might be beneficial because more HHT-causing genes can be discovered.
Families are strongly encouraged to arrange genetic testing through a medical geneticist or genetic counselor who understands all of the complexities and limitations of genetic testing for HHT.
If you are diagnosed with HHT and are experiencing one or more symptoms of the disease, treatment can help manage your symptoms to improve your quality of life and reduce the risk of life-threatening complications. With appropriate treatment, you can achieve a near-normal life expectancy.
- Moisturizing topical therapies: sprays or gels typically used during the day
- Oral antifibrinolytics (tranexamic acid): oral medication that can be used if you do not respond to moisturizing topical therapies
- Nasal packing: can be used for nosebleeds that are difficult to stop (includes liquid packing, dissolvable packing and lubricated low-pressure packing)
- Bevacizumab (Avastin): medication (nasal injection or Intravenous treatment) used to slow the growth of blood vessels and reduce nosebleeds
- Ablative therapies for nasal telangiectasias: procedures including laser treatment, radiofrequency ablation, electrosurgery and sclerotherapy
- Septodermoplasty surgery and nasal closure surgery: more invasive procedures for patients who do not experience relief with other nosebleed treatments
Brain AVMs can be successfully treated in most cases, though there is no single standard treatment for all brain AVMs in patients with HHT. Brain AVMs with high-risk features found in children with HHT should be treated and require close follow-up.
Treatment for brain AVMs includes one or a combination of the following procedures:
- Brain (cerebral) angiogram: minimally invasive procedure recommended if a brain AVM is identified on an MRI
- Brain (cerebral) embolization: procedure to block the blood flow to abnormal vessels and lessen the risk of bleeding or stroke
- Surgical Removal: fully curative surgical procedure that places a clip on the AVM or removes the AVM; has a higher complication rate than embolization
- Stereotactic Radiosurgery (Gamma Knife): focused radiation that destroys the AVM tissue; often recommended after embolization to ensure the AVM is cured
Pulmonary AVMs of a certain size should be treated.
- Pulmonary embolization: procedure performed to block the blood flow to the abnormal vessels, which eliminates the occurrence of a potentially life-threatening complication
- Surgical Removal: surgical procedure (rarely necessary following embolization) to remove the part of the lung that contains the pulmonary AVM
No treatment is recommended if you have liver AVMs that do not cause symptoms. You should receive one or more of the following treatment options if you have liver AVMs that cause symptoms or complications.
- Bevacizumab: IV medication that slows the growth of blood vessels; may help patients with both severe liver AVMs and heart failure who have failed other types of medical management
- Liver transplant: surgery considered for patients with liver AVM symptoms, especially refractory heart failure, biliary ischemia, or complicated portal hypertension
- Argon Plasma Coagulation: procedure used sparingly for bleeding lesions and significant non-bleeding lesions; completed during EGD and uses a jet of argon gas and high-frequency electric current to seal the irregular or bleeding areas
- Oral anti-fibrinolytics (tranexamic acid): oral medication that can be used for patients with mild to moderate GI bleeding
- Bevacizumab/systemic anti-angiogenic therapy: IV medication considered when other types of medical management do not relieve GI bleeding
- Management of anemia and iron deficiency
If you have HHT, you should be screened for iron deficiency and anemia, take iron replacements/IV infusions, and receive red blood cell transfusion when needed. If your doctor recommends anticoagulant or antiplatelet therapy, your bleeding risks should be considered.
- Oral iron supplements: This is the initial recommended therapy. Beyond iron-rich foods, you will need iron supplements if you are significantly iron deficient.
- IV (intravenous) iron replacement: If you do not respond to, or cannot tolerate, oral iron supplements, your doctor may recommend IV iron treatment.
- Red blood cell transfusions: If you are severely anemic and have other factors that increase your risk for complications related to anemia, your doctor may recommend these transfusions.
If your child has large AVMs or those associated with symptoms, they should be treated to avoid complications.
Our HHT Clinical Patient Care Coordinator will respond to your message within two business days (excluding weekends/holidays).
Please direct all follow-up questions and requests for medication management appointments to your UHealth care team. As an existing patient, you can request appointments and communicate with your care team in MyUHealth Chart.
If you are asked to submit your medical records to our office, please fax them to 305-243-1979 (Attn: Shannon Lange). You can request your imaging CD from the diagnostic center that performed your scans. We cannot return imaging CDs.
Mail medical imaging CDs to:
Desai Sethi Medical Center
Attn: Dr. Joseph Zikria
1150 NW 14th St.
Miami, FL 33136
Why Choose UHealth?
HHT expertise and excellence in patient care. UHealth has been named a Hereditary Hemorrhagic Telangiectasia Center of Excellence by Cure HHT. We are equipped with the personnel, expertise, commitment and resources to provide you and your family with comprehensive evaluation, management and education for HTT. Our physicians have the specialized training and expertise necessary for the diagnosis, treatment and follow-up care of adults and children with HHT.
Multidisciplinary providers. A multidisciplinary team specializing in the many areas of the body affected by HHT is important for your proper diagnosis and treatment. To provide the best care, UHealth’s experienced HHT physicians collaborate with our departments of Interventional Radiology, Genetics, Gastroenterology, Neurosurgery, Hematology, ENT, Dermatology, Pulmonology and Cardiology.
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