No abstract

Hereditary Haemorrhagic Telangiectasia (HHT) or Rendu-Osler-Weber syndrome, is an autosomal dominant rare disease characterized by localized angiodysplasia. This is manifested as epistaxis, mucocutaneous and gastrointestinal telangiectases, and arteriovenous malformations in the pulmonary, cerebral or hepatic circulation. The prevalence is between 1 in 5,000 to 8,000, although it is higher in some regions. The most frequent clinical manifestation of HHT is epistaxis, normally from light to moderate from the 4(th) decade of life. However, many patients show severe epistaxis which may interfere with their quality of life. The epistaxis is due to telangiectasia on the nasal mucosa. These are focally dilated postcapilar venules, which in advanced phases show many layers of smooth muscle cells without elastic fibers, and very frequently directly connect with dilated arterioles. As a consequence of these vascular alterations, telangiectases are very sensitive to slight trauma and even to the friction with the air when breathing, which gives rise to nose bleeds. Unfortunately, there is no optimal pharmacological treatment for the epistaxis in HHT. The use of antifibrinolytic agents for the treatment of HHT has been studied recently by our group as an effective relief for nasal and gastric haemorrhages. This work represents a systematic review and the beginning of a systematic laboratory work we are now conducting in our lab to screen for "orphan drugs" as therapeutic agents in HHT. In this context, the use of hormones, immunosuppresants and anti-angiogenic agents are under preclinical study in our laboratory.

Aim: To describe epidemiological characteristics of a wide cohort of Spanish patients with hereditary hemorrhagic telangiectasia (HHT)/ Rendu-Osler-Weber disease. Methods and Results: Between 1 January 2002 and 31 December 2013, 667 Spanish patients with suspected HHT were evaluated in the reference HHT Unit in Hospital Sierrallana and 449 were diagnosed by clinical Curaçao criteria and/or genetic test. The diagnostic sensitivity of Curaçao clinical criteria in the population studied was 94.59%. Prevalence was 1:5,936 people and lethality rate of 0.16%. Type 2 HHT was the most prevalent and in total 147 different mutations was identified. Epistaxis was the most prevalent symptom (96.88% of cases) while 95.18% of patients showed typical telangiectasias. Pulmonary involvement was present in 28.25% of patients (by computed tomography) mainly in women and HHT1 cases while liver infection was more prevalent in HHT2 cases. Brain involvement was disclosed in 28.35% of cases. Telangiectasias in conjuctival mucose were very frequent mainly in HHT1 elderly patients. Conclusion: This is the first representative series of epidemiological data on a non-previously evaluated population, showing results about prevalence, genetic distribution and organ infection and disclosing new observations that can help guide the diagnostic and screening procedures for these patients.

No abstract