The EN-RBD database was established and funded by the DG SANCO, European Community in 2007 to obtain adequate information to address the lacuna in the knowledge of clinical manifestations, treatment and genetic basis of RBDs. The project involved the participation of 13 European partners who retrospectively collected data on 592 patients affected with different types of RBDs over three years.
The relationship between laboratory phenotype and bleeding severity in patients with RBDs was explored. Clinical bleeding episodes were classified into four categories according to severity (ranging from asymptomatic to severe bleedings – grade III). A linear regression analysis showed that Fibrinogen, FV+III, FX, and FXIII had the best linear correlation between activity level and clinical severity; FV and FVII deficiencies showed a good correlation whereas FXI deficiency showed no such correlation at all. For FII, number of patients was too small to draw any correlation. Our study remains the first to classify RBDs on the basis of clinical and laboratory parameters, and to highlight significant correlations between the laboratory phenotype and clinical bleeding severity. The main limitation of our study is the retrospective nature of data collection. The observed heterogeneity between different RBDs underlines the need for a prospective data gathering tool that allows for adequate assessment of individual RBDs. Undertaking such a task is one of the future aims of the EN-RBD.
(see also Peyvandi F, et al. Coagulation factor activity and clinical bleeding severity in rare bleeding disorders: results from the European Network of Rare Bleeding Disorders. J Thromb Haemost 2012; 10:615–21)