Current therapy for rare factor deficiencies

Haemophilia A and B and von Willebrand disease account for 80-85% of all in herited bleeding disorders. The other 15% are represented by deficiencies o f fibrinogen, prothrombin, or factors V, VII, X, XI, or XIII. In addition, acquired factor deficiencies are seen in a variety of conditions ranging fr om malignancies to autoimmune disorders. The spectrum of symptoms in these conditions varies from severe and life-threatening haemorrhage to a mild bl eeding diathesis. The diagnosis depends on demonstration of decreased activ ity of one of the clotting factors. Due to the rarity of each of the indivi dual factor deficiencies, purified factor concentrates are not as readily a vailable as they are for haemophilia A and B. Treatment of rare clotting fa ctor deficiencies consists of the most purified blood product available tha t contains the missing factor. Depending on which factor is deficient, eith er purified concentrates, prothrombin complex concentrates, cryoprecipitate , or fresh frozen plasma can be used. In addition, recombinant factor VIIa is available for treating factor VII deficient patients.