Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu Disease)

Effects vary in racial and ethnic groups, with a wide geographic distribution.

Men and women affected equally.

In Vermont, frequency is 1:16,500.

In Europe and Japan, frequency is 1:5000–8000.

Excessive bleeding

Paradoxical air, bland, or septic embolism to brain

Chronic anemia due to hemorrhage, especially recurrent epistaxis.

Due to danger of intrapartum or postpartum pulm hemorrhage, a pregnant woman with HHT who has not had a recent pulm evaluation should be evaluated as soon as pregnancy is recognized.

Mucocutaneous and visceral vascular dysplasia can occur.

Combination of defective perivascular connective tissue, insufficient smooth muscle contractile element, endothelial cell junction defects, and increased endothelial tissue plasminogen activator impairing thrombus formation in case of vascular damage.

International consensus diagnostic criteria (Curacao criteria) indicates HHT diagnosis classified as definite if three criteria present, possible or suspected if two criteria present, and unlikely if one criterion present. The criteria are:

• Epistaxis: Spontaneous recurrent nosebleeds.

• Mucocutaneous telangiectasia.

• Visceral involvement (i.e., GI telangiectasia, pulm AVM, hepatic AVM, cerebral AVM, spinal AVM).

• Affected primary relative.

Manifestations of HHT are not present generally at birth but develop with increasing age, with epistaxis usually being the earliest sign that may lead to chronic anemia. About 90% of pts have signs and symptoms by age 40.