What is von Willebrand Disease?Von Willebrand disease (VWD) is an inheritable bleeding disorder. Many different proteins are needed to make a person’s blood clot successfully. People with VWD are either missing or low in the clotting protein von…
What Are Rare Bleeding Disorders?In the US, a rare disease or disorder is defined as one that affects fewer than 200,000 people. This means hemophilia A and B, and the less-common factor deficiencies such as I, II, V, VII, X, XI, XII and XIII, are…
What are Platelet Disorders?Platelets play an important role in blood clotting, so when a person has a low number of platelets, too many platelets or their platelets don’t work the way they should, they have a platelet disorder. People with platelet…
Factor I (Fibrinogen) DeficiencyFactor I deficiency is a collective term for three rare inherited fibrinogen deficiencies. It was first described in 1920 by two German physicians. Fibrinogen helps platelets stick together to form the initial “plug”…
Factor II (Prothrombin) DeficiencyFactor II (FII) deficiency, also called prothrombin deficiency, was first identified in 1947 by Dr. Armand Quick. The incidence is estimated at 1 in 2 million in the general population. Factor II deficiency is…
Factor V (Labile Factor, Proaccelerin) Deficiency (Owren’s Disease, Parahemophilia)Factor V (FV) deficiency was first described in a Norwegian patient in 1943 and reported by Dr. Paul Owren in 1947. Its incidence is about 1 in 1 million; fewer…
Factor VII (Labile Factor or Proconvertin) Deficiency (Alexander’s Disease)Factor VII (FVII), or proconvertin, deficiency was first recognized in 1951. Considered the most common of rare bleeding disorders its incidence is estimated at 1 per…
FACTOR X (Stuart-Prower Factor) DEFICIENCYFactor X (FX), or Stuart-Prower factor, deficiency was first identified in the 1950s in the US and England in two patients: Rufus Stuart and Audrey Prower. The incidence of FX deficiency is estimated at…
FACTOR XI DEFICIENCY (Hemophilia C, Plasma Thromboplastin Antecedent (PTA) Deficiency, Rosenthal Syndrome)Factor XI (FXI) deficiency, also called hemophilia C, plasma thromboplastin antecedent deficiency and Rosenthal syndrome, was first recognized…
FACTOR XII (Hageman Factor) DEFICIENCYFactor XII (FXII) deficiency, also called Hageman factor deficiency, was first identified in 1955 in John Hageman. Its incidence is estimated at 1 in a million. FXII deficiency is inherited in an autosomal…