Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)
Hereditary hemorrhagic telangiectasia is an autosomal dominant vascular dysplasia, most often from ENG or ACVRL1 mutations, causing mucocutaneous telangiectasias and visceral arteriovenous malformations diagnosed by the Curacao criteria. Management combines iron repletion and epistaxis control with lifelong screening and embolization of pulmonary arteriovenous malformations to prevent paradoxical stroke and brain abscess.
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What this article covers
- Overview
Definition: hereditary hemorrhagic telangiectasia (HHT), also called Osler-Weber-Rendu syndrome, is an autosomal dominant vascular disorder producing mucocutaneous telangiectasias and arteriovenous…
- Epidemiology
Autosomal dominant, high penetrance: a first-degree relative has a 50% inheritance chance, and features become more apparent with age.
- Risk factors
First-degree relative with HHT: the dominant risk factor, given autosomal dominant, high-penetrance inheritance.
- Pathophysiology
Impaired vascular endothelial signaling: ENG and ACVRL1 encode receptors in the transforming growth factor-beta pathway supporting vessel wall maturation; loss-of-function mutations destabilize the endothelial-smooth muscle interface.
- Clinical features
Recurrent spontaneous epistaxis: the earliest and most common manifestation, often beginning in childhood or adolescence, progressively more frequent and severe with age; usually the presenting complaint.
- Differential diagnosis
Von Willebrand disease: mucocutaneous bleeding (epistaxis, gum bleeding, menorrhagia) and a family history of bleeding, but from von Willebrand factor deficiency rather than vascular malformation…
- Diagnosis
Establish the diagnosis with the Curacao criteria, four items, and classify certainty by count: (1) recurrent, spontaneous epistaxis; (2) mucocutaneous telangiectasias at characteristic sites (lips…
- Management
Treat active severe bleeding first: resuscitate with IV fluids, transfuse packed red blood cells for hemoglobin below 7 g/dL or symptomatic blood loss, then achieve local hemostasis (nasal packing or endoscopic therapy) before escalating.
- Complications
Paradoxical embolization through pulmonary AVMs: venous material or bacteria bypass pulmonary capillary filtration and enter the systemic circulation, causing TIA, ischemic stroke, or brain abscess…
- Prognosis
Life expectancy is near normal with adequate screening and management: most morbidity and mortality comes from unrecognized visceral AVMs rather than mucocutaneous bleeding alone, so systematic screening changes outcome.
- Prevention
Screen every patient with definite or possible HHT for pulmonary AVM with transthoracic contrast echocardiography at diagnosis, and repeat roughly every 5 years in adults without a prior AVM, sooner if new symptoms develop.
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