What is HHT?

HHT affects more than 1.4 million people worldwide.

Hereditary Hemorrhagic Telangiectasia (HHT) is a genetic disorder that causes malformed blood vessels and can affect multiple organs of the body. The disorder is also sometimes referred to as Osler-Weber-Rendu (OWR) after several doctors who studied HHT in the late 1800s. More than a hundred years later, HHT is still often misdiagnosed and many doctors do not understand all of its manifestations.

of people with HHT are undiagnosed

HHT can cause bleeding in several different organs of the body. The most commonly experienced symptom is nosebleeds - 90% of people with HHT live with recurring nosebleeds. Nosebleeds in people with HHT can vary in severity from a simple nuisance to bleeds that require blood transfusion. Other commonly affected organs are the brain, lungs, and GI tract.

HHT affects males and females of all ages and from all ethnic and racial backgrounds. HHT is caused by a genetic mutation. This genetic mutation causes blood vessels to form abnormally, which can lead to the symptoms of HHT.

Answers to the most frequently asked questions about HHT.