Editorial [Hot Topic: Molecular and Clinical Aspects of Hereditary Hemorragic Telangiectasia: A Rare Disease Executive Editor: (Emilo Jirillo)]

Hereditary Hemorragic Teleangiectasia or Osler-Weber-Rendu disease represents a rare genetic disorder which is under intensive investigation in view of its multidisciplinary aspects. In the present hot topic issue entitled: "Molecular and Clinical Aspects of Hereditary Hemorragic Telangiectasia: A Rare Disease" the full spectrum of this disease has been emphasized starting from basic concepts to diagnostic criteria and innovative therapeutic procedures. In the first paper of this special issue Daina and associates [1] have pointed out the salient features of Hereditarry Hemorragic Telangiectasia (HHT), stating that this disease is more frequent than previously estimated and, therefore, diagnostic and therapeutic technologies have improved the recognition of the disease. Lenato and Guanti [2] have provided information about genetic and molecular aspects of HHT, claiming that the variability observed among members of the same family has not yet been explained , despite the sharing of the same disease-causing mutation. In three consecutive papers the immulological aspects of HHT have been investigated. The role of Transforming Growth Factor-beta in the regulation of the immune response and of cellular proliferation has been discussed [3]. In addition, novel findings demonstrate that in HHT patients the T-helper (h)-1 response is ablated, while the Th2 response seems to dominate the immune scenario [4]. This defect of the adaptive immunoresponse could downregulate the phagocytic activity, as observed in another group of patients [5]. Sabba and associates [6] have outlined the broad spectrum of clinical manifestation observed in all organs in HHT patients. Giordano and associates [7] have placed emphasis on the pediatric aspects of HHT with the aim to establish reliable screening protocols for the prevention and cure of the disease. Memeo and associates [8] have illustrated some diagnostic imaging procedures for visceral involvement and, in particular, ultrasonography seems to be the best screening modality for hepatic and pulmonary localizations. Geisthoff and associates [9] have reviewed all the therapeutical treatments for recurrent hepistaxis in HHT. Endovascular treatment of pulmonary and cerebral arteriovenous malformations in HHT patients has been presented by De Cillis and associates [10]. Finally, Pasculli and associates [11] have concluded that appropriate screening programs are mandatory and multispecialistic cooperation is needed. Special Centers developed in the world are currently working to formulate better therapeutical approaches for HHT based on gene therapy in order to cure this condition. References [1] Daina E, D'Ovidio F, Sabbà C. Introduction: Hereditary Hemorragic Telangiectasia as a rare disease. Curr Pharm Design 2006; 12(10): 1171-1172. [2] Lenato GM, Guanti G. Hereditary Haemorrhagic Telangiectasia (HHT): genetic and molecular aspects. Curr Pharm Design 2006; 12(10): 1173-1193. [3] Jirillo E, Amati L, Suppressa P, Cirimele D, Guastamacchia E, Covelli V, Tafaro E, Sabbà C. Involvement of the transforming growth factor b in the pathogenesis of hereditary hemorrhagic teleangiectasia. Curr Pharm Design 2006; 12(10): 1195-1200. [4] Amati L, Passeri ME, Resta F, Triggiani V, Jirillo E, Sabbà C. Ablation of T-Helper 1 cell derived cytokines and of monocyte-derived tumor necrosis factor b in hereditary hemorrhagic teleangiectasia: immunological consequences and clinical considerations. Curr Pharm Design 2006; 12(10): 1201-1208. [5] Cirulli A, Loria MP, Dambra P, Di Serio F, Ventura MT, Amati L, Jirillo E, Sabbà C. Patients with hereditary hemorrhagic telangectasia (HHT) exhibit a deficit of polymorphonuclear cell and monocyte oxidative burst and phagocytosis: a possible correlation with altered adaptive immune responsiveness in HHT. Curr Pharm Design 2006; 12(10): 1209-1215. [6] Sabbà C, Gallitelli M, Pasculli G, Suppressa P, Resta F, Guastamacchia E, Tafaro E. HHT: a rare disease with a broad spectrum of clinical aspects. Curr Pharm Design 2006; 12(10): 1217-1220. [7] Giordano P, Nigro A, Del Vecchio GC, Sabba C, De Mattia D. HHT in childhood: screening for special patients. Curr Pharm Design 2006; 12(10): 1221-1225. [8] Memeo M, Scardapane A, Stabile Ianora AA, Sabbà C, Angelelli G. Hereditary hemorrhagic teleangiectasia: diagnostic imaging of visceral involvement. Curr Pharm Design 2006; 12(10): 1227-1235. [9] Geisthoff UW, Fiorella ML, Fiorella R. Treatment of recurrent epistaxis in HHT. Curr Pharm Design 2006; 12(10): 1237-1242. [10] De Cillis E, Burdi N, Bortone AS, D'Agostino D, Fiore T, Ettorre GC, Resta M. Endovascular treatment of pulmonary and cerebral arteriovenous malformations in patients affected by hereditary hemorrhagic teleangiectasia. Curr Pharm Design 2006; 12(10): 1243-1248. [11] Pasculli G, Sallustio G, Sabbà C. The need for an interdisciplinary network of investigations on HHT. Curr Pharm Design 2006; 12(10): 1249-1251.