Snapshot A 25-year-old man presents to the emergency department for a nosebleed. He says that the bleeding began earlier in the morning and occurred spontaneously. He denies any trauma to the nose or inhaling medications or illicit drugs through the nose. He has tried applying pressure to the nose but the bleeding still persists. He has a history of multiple episodes of epistaxis requiring medical attention. On physical exam, he has multiple telangiectasias on his lips. Introduction Definition an autosomal dominant vascular disorder that is also known as hereditary hemorrhagic telangiectasia (HHT) this disorder is characterized by epistaxis arteriovenous malformations (AVMs) telangiectasias (small vascular malformations) Pathophysiology autosomal dominant genetic mutations that result in an abnormal vasculature (e.g., AVMs) Presentation Clinical presentation epistaxis patients can have recurrent episodes visceral lesions gastrointestinal telangiectasia pulmonary AVMs can result in embolic stroke and cerebral abscess this results by the AVM creating a path for venous blood to bypass the pulmonary circulation cerebral AVMs can result in hemorrhagic stroke telangiectasias Studies Iron deficiency anemia secondary to blood loss Treatment Management is directed at the site of involvement e.g., nasal lubrication and laser treatment for epistaxis Complications Hemorrhagic and embolic stroke Iron deficiency anemia Gastrointestinal bleeding Pulmonary hypertension