Blood Clotting Disorder Hereditary Hemorrhagic Telanfiectasia

Unlike many bleeding disorders that affect one or more clotting factors (substances in the blood that help with clotting) in the body, hereditary hemorrhagic telangiectasia (HHT) is a disorder that affects the smaller arteries in the body.

This condition can be present as either:

  • a defective connection within vein channels
  • an extreme thinness of the arteries.

Both lead to easy bruising and artery damage.

The disorder is also known as Osler-Weber-Rendu (OWR), named after three doctors who studied the disease over 100 years ago. In 1896, Dr. Rendu differentiated this disorder from the more commonly known blood disorder hemophilia, indicating that common symptoms of hemorrhagic telangiectasia included abnormal nosebleeds and trademark red spots (called telangiectases) that are not present with hemophilia.

Affected arteries bleed more easily, leading to tiny internal lesions that create the red spots known as telangiectases.

HHT Causes

Hereditary hemorrhagic telangiectasia is an inherited genetic disorder that affects approximately 1 in 5,000 people. The disorder affects males and females across the racial spectrum evenly. For those affected by HHT, most of the blood vessels are structurally normal. However, although only a small percentage of the blood vessels pose a problem, these abnormal blood vessels must be treated for health and sometimes cosmetic reasons.

For many people, the disorder does not manifest prominently until young adulthood, leading to difficulty or delay in diagnosis. The problematic arteries tend to grow and multiply through a person’s 20s and 30s.

In a vast majority of cases (80 percent), those who suffer from HHT have a parent that also has the disease. Surface telangiectases can be seen through the surface of the skin and manifest as bright red spots. For many, the symptoms are mild and easily treated with a comprehensive medical approach. For a small minority, however, serious symptoms and problems can arise when the disease is not attended to properly.

Testing for HHT

Genetic testing can be done to determine whether or not a person has HHT. Yet, this type of test is often expensive and unnecessary. Based on a thorough family history and an examination of symptoms, a doctor can usually make an accurate diagnosis.

Doctors diagnose HHT if patients fit into three of the following categories:

  • The patient has a family history of HHT.
  • The patient has multiple external telangiectases, or red spots which mostly occur in the fingers, lips and/or nose.
  • The patient has multiple internal teleangiectases, which mostly occur in the brain, liver and/or lungs.
  • The patient has recurrent spontaneous nosebleeds.

HHT Treatments

Treatment for HHT depends in large part on the symptoms the disease is causing. For simple problems, such as nosebleeds, the first line of defense will be practical home remedies, such as using a humidifier and applying topical ointments to lubricate the internal mucosa of the nose (to prevent and help bleeding episodes).

If this is insufficient, more serious measures may be taken. These can include:

  • laser therapy
  • septal dermoplasty, a skin graft inside the nose that adds a thicker layer of skin to the area prone to problems.

The nose is not the only area that can be affected by these telangiectases. They can also occur on the surface of the skin (often on the face or hands) or within the body in the gastrointestinal tract or lungs. Patients with the disorder should regularly see a specialist who can keep an eye on internal issues, treat them as they arise and hopefully catch HHT complications before they cause any more serious health problems.

With proper diagnosis, treatment and responsible care, most HHT patients can lead completely normal lives.


Hereditary Hemorrhagic Telangiectasia (2007). About HHT. Retrieved September 24, 2007, from the HHT Web site:

University of Michigan Health System (2007). Hereditary Hemorrhagic Telangiectasia (HHT) Syndrome. Retrieved September 24, 2007, from the University of Michigan Web site: