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In This Topic
Blood Disorders
Bleeding Due to Abnormal Blood Vessels
Hereditary Hemorrhagic Telangiectasia
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Chapters in Blood Disorders
  • Biology of Blood
  • Symptoms and Diagnosis of Blood Disorders
  • Blood Transfusion
  • Iron Overload
  • Anemia
  • Blood Clotting Process
  • Bleeding and Clotting Disorders
  • Bleeding Due to Abnormal Blood Vessels
  • Platelet Disorders
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  • Plasma Cell Disorders
  • Leukemias
  • Lymphomas
  • Myeloproliferative Disorders
  • Spleen Disorders
Topics in Bleeding Due to Abnormal Blood Vessels
  • Overview of Blood Vessel Disorders
  • Autoerythrocyte Sensitization
  • Protein Disorders Causing Blood Vessel Disorders
  • Hereditary Hemorrhagic Telangiectasia
  • Purpura Simplex (Easy Brusing)
     
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    Hereditary Hemorrhagic Telangiectasia

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    Hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome) is a hereditary disorder in which blood vessels are malformed, making them fragile and prone to bleeding.

    • Dilated blood vessels (telangiectasia) are present on the skin and the lining of the mouth, nose, and digestive tract.
    • When blood vessels break, people develop active bleeding from these vessels, especially those within the nose.
    • Usually the appearance of the dilated blood vessels on the lips and tongue give doctors enough information to make a diagnosis.
    • Doctors stop the episode of bleeding and may give iron supplements or blood transfusions if the person has anemia.

    Blood vessels under the skin may break and bleed, causing small, red-to-violet discolorations, especially on the face, lips, lining of the mouth and nose, and tips of the fingers and toes. Severe nosebleeds may also occur. Small blood vessels in the digestive and urinary tracts, as well as in the brain, liver, lungs, and spinal cord, may also be affected, causing bleeding in these sites.

    Some patients have abnormal connections between an artery and a vein (arteriovenous fistula). If this artifical connection is in a lung, blood passes through the lungs without receiving enough oxygen. The person may be short of breath, feel tired, or have skin that appears bluish. An arteriovenous fistula in the brain may result in a stroke or transient ischemic attack. Arteriovenous fistulas that develop in the brain or spinal cord may cause seizures or paraylsis and those that occur in the liver may cause liver failure or heart failure.

    Doctors usually make the diagnosis after an examination reveals the typical dilated blood vessels on the face, around the mouth, and on the fingers and toes. Sometimes doctors need imaging tests to examine the digestive and urinary tracts. If the diagnosis still is not clear, genetic testing is available and reveals mutations in 80% of people.

    Photographs

    Hereditary Hemorrhagic Telangiectasia

    Hereditary Hemorrhagic Telangiectasia

    At puberty and at the end of adolescence, doctors screen people with family members who have arteriovenous fistulas. Screening usually consists of imaging of the lungs, liver, and brain.

    Treatment is aimed at stopping an occurrence of bleeding. Treatment may involve applying pressure, using a topical drug that narrows blood vessels (astringent), or using a laser beam to destroy the leaking blood vessel. Severe bleeding may require more invasive techniques, including surgery. Bleeding almost always recurs, resulting in iron deficiency anemia. People with hereditary hemorrhagic telangiectasia often need to take iron supplements. People may also need repeated blood transfusions. Some people may also need to take drugs that inhibit the breakdown of blood clots (to help minimize bleeding).

    Last full review/revision January 2013 by David J. Kuter

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    Pronunciations

    arteriovenous fistula

    fistula

    hereditary hemorrhagic telangiectasia

    ischemic

    telangiectasia

    transient ischemic attack

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    Next: Purpura Simplex (Easy Brusing)

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