Definition - Rare Bleeding Disorder Database



		Manifestation	Phenotype	Genotype	Correlation	Treatment	References

	Definition

	Rare bleeding disorders (RBDs) are very rare diseases, relatively neglected until recently by health care providers, advocacy organizations and pharmaceutical companies. Haemophilia A and B are the most frequent inherited bleeding disorders. Together with von Willebrand disease, a defect of primary hemostasis associated with a secondary defect in coagulation factor VIII (FVIII), these X-linked disorders include 95% to 97% of all the inherited deficiencies of coagulation factors -1-.

	The other 3-5% are represented by the less common inherited disorders. This include deficiency of fibrinogen, prothrombin, factors V, combined V+VIII, VII, X, XI and XIII. These disorders are inherited in an autosomal recessive manner (Figure 1) and their prevalence is approximately 1:500.000 or less in the general population of western countries (Table 1) -1- However their frequency is increased 10-20 times where consanguineous marriages are practised such as Middle East countries and in Southern India *- 2*-.

	The natural history and spectrum of clinical manifestations of RBDs are not well established, since few centres in the world have the opportunity to see a significant number of these rare patients.