Hereditary haemorrhagic telangiectasia: state of the art.

Hereditary haemorrhagic teleangiectasia (HHT) or Rendu-Osler-Weber disease is a genetic autosomal-dominant disorder characterised by the presence of vascular telangiectases in mucocutaneous tissues, visceral organs and the Central Nervous System. Pulmonary arteriovenous malformations have a variable incidence rate ranging between 15-33%, and the safest treatment is transcatheter embolotherapy. Haemmorrhages from the gastrointestinal tract occur in 10-40% of patients with HHT localized in duodenum and colon and can be treated with endoscopy and laser coagulation, but this procedure is not efficacious for vascular anomalies in small intestine since this site cannot be easily reached. The prevalence of cerebrovascular malformations in hereditary haemorrhagic telangiectasia patients is 5-27%, and there are several types described including telangiectasias, cavernous angiomas, arteriovenous malformations, and aneurysms. Cerebrovascular malformations can be treated by: neurovascular surgery, embolization, and stereotactic radiosurgery, but the appropriate course of action for dealing with asymptomatic cerebrovascular malformations is still debated. The most common symptom in HHT patients is epistaxis, which can sometimes be so profuse that it requires multiple transfusions and iron supplementation. Nose bleeds begin before 10 years of age and become more severe in later decades. A multitude of different treatments are available, tailored to the severity of epistaxis. These include: hormonal therapy with oestrogens, application of fibrine tissue sealant, laser coagulation, embolization and septal dermoplasty using Saunder's technique. Aim of this study is to review diagnostic and therapeutic techniques, since continuous growth and danger of these arteriovenous malformations require early diagnosis, adequate treatment, prolonged follow-up and screening of the family.