Hereditary Haemorrhagic Telangiectasia
Background
Hereditary Haemorrhagic Telangiectasia: HHT; Hereditary Hemorrhagic Telangiectasia - US; Osler-Rendu-Weber; Rendu-Osler-Weber
Hereditary Haemorrhagic Telangiectasia is a genetic disorder that leads to the development of abnormally wide and fragile blood vessels.
Most people affected by HHT experience two problems:
A few people will have abnormal vessels elsewhere. The lungs are affected in 1 in 5 individuals with HHT and it is important that this is recognised (see below). For other sites, such as the liver and brain, it is not clear that any specific tests or treatment are needed if they are not causing problems already.
About 1 in 5 individuals with HHT develops abnormal vessels in the lungs. These are called pulmonary arteriovenous malformations (PAVMs). These malformations let blood bypass or 'shunt' past the lung airsacs. They are particularly important because individuals who have PAVMs are at risk of having a ministroke or brain abscess even if they feel well. In addition, a few women with PAVMs have complications during pregnancy. It is therefore important to check whether or not PAVMs are present, and if so, arrange for a simple treatment to close them off.
Inheritance patterns and prenatal diagnnosis ![]()