Specific Complications of HHT: Intestinal AVM

A large percentage of patients with HHT have intestinal AVM, but only 20% of HHT patients develop significant stomach or intestinal bleeding. Bleeding usually does not occur before age 50.

These AVM can usually be detected by endoscopy, which involves inserting a flexible tube with a camera on the end through your mouth or rectum to look inside the intestines.

The biggest problem with bleeding is that it lead to anemia, which can cause a person to feel tired all the time and look pale. 

General Information & Prevention

• If you have high blood pressure, this should be kept under control.

• Avoid blood thinners or nonsteroidal antiinflammatory medicines like aspirin and ibuprofen as they can worsen bleeding tendencies.  Tylenol®, Bextra®, Celebrex®, and Vioxx® are generally okay.

• Report any of the following symptoms to your doctor as soon as possible:

  • vomiting blood
  • passage of bright red or dark black bowel movements
  • worsening shortness of breath or fatigue
  • pale skin

Treatment Options

• Iron therapy: Iron can be taken either orally or intravenously to help build up your blood count to help treat symptoms of fatigue. Intravenous iron can be given as an outpatient every 2 to 4 weeks, and is usually arranged through a hematologist.
• Laser: This involves using an endoscopy to see the AVM, and then firing a laser at the AVM to destroy them. This may be effective if a person has only a few AVM. However, most patients have too many AVM in the intestines for laser to be effective.
• Blood transfusion: This may be required to build your blood count back up if it falls to a seriously low level due to bleeding.  This can usually be done as an outpatient.
• Oral hormones: Hormone pills like estrogen and danazol may shrink AVM and decrease the frequency and severity of bleeding. Some HHT doctors believe that these treatment work for some patients, but this has never been proven in a research study. Side effects include an increase risk of blood clots in both sexes and breast enlargement in males.
• Tranexamic acid (Amicar®): This pill works by increasing the rate of clotting. There are reports of success, but it has never been proven in a research study. Side effects include an increase risk of blood clots.