No abstract

Hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber disease, is an autosomal dominant disorder of the fibrovascular tissue. It is characterized by the classic triad of (muco-)cutaneous telangiectases, arteriovenous malformations with recurrent epistaxis and hemorrhages, and inheritance. A wide variety of clinical manifestations in HHT have been described. In more than 90% of the patients, nosebleeds are the first predominant symptom, therefore ENT physicians often play a key role as far as diagnosis and management of the disease are concerned. In spite of recent diagnostic and therapeutic progress, a cure for this often burdening and handicapping disease is still not available. Apart from affecting the nose, arteriovenous malformations (AVMs) may also affect the skin, lungs, brain, liver and gastrointestinal tract. The two known genes that are implicated in HHT are endoglin (ENG) located on chromosome 9q33-q34 and activin-receptor-like kinase (ALK1) located on chromosome 12q13. Mutations of ENG are observed in HHT type 1 with an incidence up to 40% for pulmonary AVMs, whereas mutations of ALK1 are observed in HHT type 2 with an incidence of only 14% for pulmonary AVMs, which clinically distinguishes these two types of mutation. The emphasis of this paper is mainly on the clinical manifestation, molecular genetics and diagnosis of HHT, taking account of current literature on HHT in order to better understand the complexity of the disease. Recent therapeutic options in the treatment of HHT have been omitted from this paper as they are subject of a following paper. HHT is more common than previously thought and shows a broad range of different clinical organ manifestations that can be sources of substantial morbidity and mortality, making HHT a continuing challenge for many sub-specialties where interdisciplinary diagnostic screening is mandatory in the management of the disease.

The aim of this study was to assess the value of topically applied estrogens in patients with hereditary hemorrhagic telangiectasia. Twenty-six patients with this disorder were treated with argon plasma coagulation and randomized into 2 groups: group A, which had postoperative application of estriol ointment (n = 14), and group B, which had postoperative application of dexpanthenol ointment (n = 12). Over a period of 12 months, the frequency and intensity of bleeding, the patient's satisfaction, and the success of the treatment were evaluated with a questionnaire. Before the operation, more than 90% of the patients in both groups complained of daily episodes of epistaxis. Twelve months after treatment, the frequency and intensity of bleeding had significantly decreased in group A as compared to group B. Of the patients in group A, 93% were satisfied with the treatment. Of the patients in group B, only 42% were satisfied with the treatment. In both groups, more than 90% of the patients were willing to undergo the same treatment again. The combined treatment approach with argon plasma coagulation and topical estriol enables us to significantly prolong the hemorrhage-free interval.