Hereditary Hemorrhagic Telangiectasia

Hereditary Hemorrhagic Telangiectasia 

Definition

Hereditary hemorrhagic telangiectasia is an inherited condition characterized by abnormal blood vessels which are delicate and prone to bleeding. Hereditary hemorrhagic telangiectasia is also known as Rendu-Osler-Weber disease.

Description

The term telangiectasia refers to a spot formed, usually on the skin, by a dilated capillary or terminal artery. In hereditary hemorrhagic telangiectasia these spots occur because the blood vessel is fragile and bleeds easily. The bleeding may appear as small, red or reddish-violet spots on the face, lips, inside the mouth and nose or the tips of the fingers and toes. Other small telangiectasias may occur in the digestive tract.

Unlike hemophilia, where bleeding is caused by an ineffective clotting mechanism in the blood, bleeding in hereditary hemorrhagic telangiectasia is caused by fragile blood vessels. However, like hemophilia, bleeding may be extensive and can occur without warning.

Causes and symptoms

Hereditary hemorrhagic telangiectasia, an autosomal dominant inherited disorder, occurs in one in 50,000 people.

Recurrent nosebleeds are a nearly universal symptom in this condition. Usually the nosebleeds begin in childhood and become worse with age. The skin changes begin at puberty, and the condition becomes progressively worse until about 40 years of age, when it stabilizes.

Diagnosis

The physician will look for red spots on all areas of the skin, but especially on the upper half of the body, and in the mouth and nose and under the tongue.

Treatment

There is no specific treatment for hereditary hemorrhagic telangiectasia. The bleeding resulting from the condition can be stopped by applying compresses or direct pressure to the area. If necessary, a laser can be used to destroy the vessel. In severe cases, the leaking artery can be plugged or covered with a graft from normal tissue.

Prognosis

In most people, recurrent bleeding results in an iron deficiency. It is usually necessary to take iron supplements.

Prevention

Hereditary hemorrhagic telangiectasia is an inherited disorder and cannot be prevented.

Resources

Organizations

American Medical Association. 515 N. State St., Chicago, IL 60612. (312) 464-5000. http://www.ama-assn.org.

Association of Birth Defect Children. 3526 Emerywood Lane, Orlando, FL, 32806. (305) 859-2821.

Key terms

Autosomal dominant — A pattern of inheritance in which the dominant gene on any non-sex chromosome carries the defect.

Chromosome — A threadlike structure in the cell which transmits genetic information.

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hereditary hemorrhagic telangiectasia

n.

An inherited disease, usually beginning after puberty, characterized by multiple telangiectases and by fragile capillaries that break easily and bleed into the skin and mucous membranes. Also called Rendu-Osler-Weber disease, Rendu-Osler-Weber syndrome.