OslerWeberRendu

Osler-Weber-Rendu disease, also known as hereditary hemorrhagic telangiectasia (HHT), is a dominantly inherited vascular disorder characterized by mucocutaneous telangiectasias and arteriovenous malformations (AVMs) in multiple organs. The combination of recurrent epistaxis, skin and mucosal telangiectasias, and visceral AVMs can lead to iron-deficiency anemia and potentially serious hemorrhagic or shunting complications.

Genetically, HHT is autosomal dominant with variable expressivity. Mutations most commonly affect the ENG gene (endoglin), ACVRL1/ALK1, and SMAD4, which disrupt TGF-beta/BMP signaling and vascular development. Other rare variants have been described. The condition shows wide clinical variability even within families.

Clinical features typically begin in childhood or adolescence. Epistaxis is common and may be persistent. Mucocutaneous telangiectasias appear on the lips, tongue, face, and fingertips. Visceral AVMs frequently involve the lungs, liver, and brain. Pulmonary AVMs can cause hypoxemia and increase the risk of brain abscess or stroke; hepatic AVMs may lead to high-output heart failure or portal hypertension; cerebral AVMs carry a risk of hemorrhage. Gastrointestinal telangiectasia can bleed and contribute to anemia.

Diagnosis relies on the Curacao criteria: spontaneous recurrent epistaxis, mucocutaneous telangiectasia, visceral AVMs, and a family history. A definite diagnosis requires three criteria; two criteria suggest probable disease. Imaging studies (CT/MRI for AVMs, echocardiography with contrast for pulmonary AVMs) and genetic testing support diagnosis.

Management is multidisciplinary and supportive. Epistaxis may be managed with humidification, topical therapies, laser or sclerotherapy, and iron supplementation; tranexamic acid is sometimes used. Visceral AVMs are treated with targeted therapies such as endovascular embolization for pulmonary AVMs or hepatic/neuronal interventions as indicated. Antibiotic prophylaxis for dental procedures is advised in patients with pulmonary AVMs to reduce brain abscess risk. Family members should be offered evaluation given the hereditary nature of the disease.

Screening and monitoring aim to detect AVMs early and address complications, with ongoing follow-up by genetics and relevant specialists to improve quality of life and prognosis.