Hereditary hemorrhagic telangiectasia (tuh-lan-jee-uk-TAY-zhuh) is a disorder that affects blood vessels. It can cause bleeding in the digestive tract, anemia, increased risk of stroke and other symptoms. In most cases, hereditary hemorrhagic telangiectasis (HHT) isn't life-threatening and symptoms can be effectively managed.

With HHT, also known as Osler-Weber-Rendu disease, some of the networks of blood vessels that join arteries to veins (capillaries) aren't correctly formed. In small blood vessels, these abnormalities are called telangiectases. When they occur in larger vessels, they're called arteriovenous malformations (AVMs). People who have HHT may have both kinds of malformations.

HHT is genetic and can affect people at any age. Its severity can vary greatly from person to person, even within the same family.


Signs and symptoms of hereditary hemorrhagic telangiectasia include:

  • Nosebleeds
  • Lacy red vessels, particularly on the lips and in the mouth
  • Blood in the stool
  • Iron deficiency anemia

Hereditary hemorrhagic telangiectasia care at Mayo Clinic

July 17, 2018
  1. AskMayoExpert. Hereditary hemorrhagic telangiectasia. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2015.
  2. Hereditary hemorrhagic telangiectasia — HHT. Society of Interventional Radiology. http://www.sirweb.org/patients/hereditary-hemorrhagic-telanglectasia. Accessed Nov. 9, 2015.
  3. Cummings KW, et al. Pulmonary vascular diseases. Clinics in Chest Medicine. 2015;36:235.
  4. Feldman M, et al. Vascular disorders of the gastrointestinal tract. In: Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management. 10th ed. Philadelphia, Pa.: Saunders Elsevier; 2016. http://www.clinicalkey.com. Accessed Nov. 10. 2015.
  5. Epperia N, et al. Blessing for the bleeder: Bevacizumab in hereditary hemorrhagic telangiectasia. Clinical Medicine Research. 2015;13:32.
  6. Wain K, et al. Hereditary hemorrhagic telangiectasia and risks for adverse pregnancy outcomes. American Journal of Genetics. Part A. 2012;158A:2009.
  7. EASL Clinical Practice Guidelines: Vascular diseases of the liver. Journal of Hepatology. In press. Accessed Nov. 17, 2015.
  8. Camaschella C. Iron-deficiency anemia. New England Journal of Medicine. 2015;372:1832.
  9. Shovlin C. Clinical manifestations and diagnosis of hereditary hemorrhagic teleangiectasia. https://www.uptodate.com/contents/search. Accessed July 16, 2018.
  10. About HHT. HHT Foundation. http://curehht.org. Accessed Nov. 17, 2015.
  11. Gossage JR. Therapeutic approach to adult patients with pulmonary arteriovenous malformations. http://www.uptodate.com/home. Accessed Nov. 17, 2015.
  12. Barbara Woodward Lips Patient Education Center. Hereditary hemorrhagic telangiectasia. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2005.
  13. Patient information: Arteriovenous malformations in the brain (The Basics). http://www.uptodate.com/home. Accessed Nov. 17, 2015.
  14. Gossage JR. Pulmonary arteriovenous malformations: Clinical features and diagnostic evaluation in adults. http://www.uptodate.com/home. Accessed Nov. 17, 2015.