Hereditary hemorrhagic telangiectasia (tuh-lan-jee-uk-TAY-zhuh) is a condition that's passed through families, called inherited. It causes atypical links between arteries and veins called arteriovenous malformations (AVMs). The most common sites AVMs affect are the skin, nose, digestive system, lungs, brain and liver.

AVMs may get larger over time. They can bleed or burst. This can result in serious complications, including death.

Nosebleeds that happen for no known reason are the most common symptom. Nosebleeds can happen every day. Ongoing bleeding from the nose and the intestinal tract can result in serious iron deficiency anemia and poor quality of life.

Also called Osler-Weber-Rendu disease and HHT, hereditary hemorrhagic telangiectasia passes from parents to children. How bad it is can vary greatly from person to person, even within the same family.

If you have HHT and have children, you may want to have them checked for the condition. HHT can affect them even if they don't have symptoms.

Symptoms of HHT include:

• Nosebleeds. These can happen every day. They often start in childhood.
• Lacy red vessels or tiny red spots, mostly on the lips, face, fingertips, tongue and inside the mouth. These are called telangiectasias.
• Iron deficiency anemia due to bleeding from the nose or intestinal tract.
• Shortness of breath.
• Headaches.
• Seizures.
• Pus-filled swelling in the brain, called a brain abscess, and strokes.
• Infection in a bone, called osteomyelitis.

HHT is a condition of gene changes, called genetic, that you get from your parents. It is an autosomal dominant disorder. That means if one of your parents has HHT, you have a 50% chance of getting it. If you have HHT, each of your children has a 50% chance of getting it from you.

The major risk factor for hereditary hemorrhagic telangiectasia is having a parent with the condition.

Your healthcare professional may diagnose HHT based on a physical exam, results of imaging tests and a family history. But some symptoms may not show up in children or young adults. Having genetic testing for HHT may confirm the diagnosis.

Imaging tests

In HHT, atypical links called arteriovenous malformations, also called AVMs, happen between arteries and veins. HHT AVMs can be present in internal organs such as the lungs, brain and liver. One or more of the following imaging tests can help find AVMs:

• Ultrasound. This test can show whether the AVMs affect the liver.
• MRI. This scan can check for AVMs in the brain as well as the liver and other organs in the belly.
• Echocardiogram bubble study. During this echocardiogram test, a healthcare professional puts a line in a vein, called an IV. A small amount of air bubbles put into the IV lets the healthcare professional find and assess any lung AVMs.
• CT scan. These can confirm AVMs in the lungs, the liver and other organs in the belly.

If you or your child has HHT, if you can, seek treatment at an HHT Center of Excellence. HHT is a rare condition that is best managed at centers that treat all aspects of this condition at every age. So it can be hard to find a specialist to treat it.

In the United States, Cure HHT names HHT Centers of Excellence for being able to diagnose and treat all aspects of the condition. Mayo Clinic is an HHT Center of Excellence and cares for many people and their family members diagnosed with HHT.

Medications

Medicines that help stop the bleeding linked with HHT can be divided into three broad groups:

• Hormone-related drugs. Medicines that have estrogen can be helpful. But side effects are common with the high doses needed. Anti-estrogens such as tamoxifen (Soltamox) and raloxifene (Evista) also can control HHT.
• Medicines that block blood vessel growth. One treatment for HHT is bevacizumab (Avastin). Avastin goes through a tube in a vein, called intravenous. Other medicines healthcare professionals use to block blood vessel growth include pazopanib (Votrient), pomalidomide (Pomalyst) and tacrolimus (Prograf, Protopic, others).
• Medicines that slow clot dissolving. Tranexamic acid (Cyklokapron, Lysteda) can help stop serious bleeding in emergencies. If taken regularly, it may help prevent bleeding.

If you get iron deficiency anemia, you might get an iron replacement through a vein. This most often works better than taking iron pills.

Surgical and other procedures for the nose

Serious nosebleeds are one of the most common signs of HHT. These sometimes happen daily. They can cause so much blood loss that you become anemic. You might need to receive blood, called a transfusion, and iron through an arm vein.

Procedures to lower the number of nosebleeds and lessen how bad they are may include:

• Ablation. This procedure uses energy from lasers or other devices to seal the vessels that cause the nosebleeds. But this most often is short-lived. The nosebleeds come back over time.
• Skin graft. Skin from another part of the body can be put inside the nose. The skin most often comes from the thigh. Healthcare professionals rarely do this procedure anymore because of how well newer medicines work.
• Surgically closing the nostrils. If nothing else works, joining flaps of skin within the nose to close the nostrils often is a success. This is done only when other treatments have failed. Healthcare professionals rarely do this procedure anymore because of how well newer medicines work.

Surgical and other procedures for the lungs, brain and liver

HHT most often affects the lungs, brain and liver. Procedures to treat AVMs in these organs may include:

• Embolization. In this procedure, a healthcare professional threads a long, slender tube through the blood vessels to the AVM. Then the health professional puts in a plug or a metal coil to block blood from entering the AVM. This shrinks and heals the AVM over time. Embolization treats lung and brain AVMs, but not liver AVMs.
• Surgical removal. Rarely, the best way to treat certain AVMs in the brain or the lungs is to remove them with surgery.
• Stereotactic radiotherapy. This procedure treats AVMs in the brain. It uses beams of radiation that come from different directions. They meet at the AVM to treat it.
• Liver transplant. Rarely, treatment for AVMs in the liver is a liver transplant.

To help prevent HHT nosebleeds, you may want to:

• Not use certain medicines. Your risk of bleeding can be higher from using certain medicines and drugs you get without a prescription. These include aspirin, ibuprofen (Advil, Motrin IB, others), fish oil supplements, ginkgo and St. John's wort.
• Not eat certain foods. In some people, having blueberries, red wine, dark chocolate or spicy foods can cause HHT nosebleeds. Try keeping a food diary to see if there's any link between what you eat and how bad your nosebleeds are.
• Keep your nose moist. Use saline sprays, lotions or gels that add moisture to help lower the risk of bleeding. Using a bedside humidifier overnight also is helpful.
• Not do heavy lifting. Bending over and lifting heavy objects can cause nosebleeds.

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything you need to do before you arrive, such as fasting before having a certain test. Make a list of:

• Your symptoms, and when they began.
• Key personal information, including major stresses, recent life changes and family medical history.
• All medicines, vitamins or other supplements you take, including the doses.
• Questions to ask your healthcare professional.

Take a family member or friend along, if possible, to help you remember what your healthcare team tells you.

Some basic questions to ask include:

• What's likely causing my symptoms?
• What tests do I need?
• Is my condition likely to go away or last?
• What treatment do you suggest?
• I have these other health conditions. How can I best manage them together?
• Are there restrictions I need to follow?
• Should I see a specialist?
• Are there brochures or other printed material I can have? What websites do you suggest?

Be sure to ask all the questions you have.

What to expect from your doctor

Your healthcare professional is likely to ask you questions, such as:

• Have your symptoms been ongoing or do they come and go?
• How bad are your symptoms?
• What, if anything, seems to make your symptoms better?
• What, if anything, seems to make your symptoms worse?