Hereditary Hemorrhagic Telangiectasia

Hereditary Hemorrhagic Telangiectasia, also known as Osler–Weber–Rendu disease and Osler–Weber–Rendu syndrome, is a genetic disorder that leads to abnormal blood vessel formation in the skin, mucous membranes, and often in organs such as the lungs, liver, and brain. This is an equal opportunity disorder; all ethnicities and all genders are similarly affected. It affects about 1 in every 5,000 people.

HHT is a disorder you inherit from one of your parents. It’s an autosomal dominant disorder, meaning that if one of your parents has HHT, you have a 50/50 chance of inheriting the dominant gene responsible for HHT. If you inherit this gene, you will have Hereditary Hemorrhagic Telangiectasia.

Symptoms and Diagnosis

The presence of telangiectasias is one indication of HHT. Other clues that might lead to a diagnosis include:

  • frequent nosebleeds
  • anemia
  • bloody stools
  • having a parent with the syndrome

If you have HHT, your doctor might want to do additional tests. For example:

  • A blood test can check for anemia, or iron deficiency in the blood.
  • A CT scan can show internal AVMs, such as in the lungs, liver, and brain.
  • A gastrointestinal doctor can insert a small camera down your throat to check for AVMs in your esophagus.
  • An echocardiogram uses sound waves to check blood flow in and out of your heart.
    If you have HHT, you should be screened for AVMs in the lungs and brain. This can help your doctor detect a potentially dangerous problem before something goes wrong. An MRI can screen for problems in the brain. CT scans can detect lung AVMs.


  • HHT affects both men and women equally, as well as different races and ethnicity.
  • It takes an average of 30 years to be diagnosed with HHT.
  • HHT is lister as a “rare disease” by the Office of Rare Diseases.
  • Only 10% of people with HHT know about it. The other 90% go undiagnosed.