A Novel Mutation Case of Type 3 Von Willebrand Disease Misdiagnosed as Hemophilia A

Abstract

VWD is reported as the most common inherited bleeding disorder worldwide, found in approximately 1% population [1-4]. It can be divided into 3 subtypes: type 1, type 2 and type 3, caused by quantitative or qualitative defects of VWF. VWF is a complex plasma protein essential for primary hemostasis and coagulation. VWF helps to bind and stabilize blood clotting FVIII from rapid breakdown within the blood stream. Any defect in VWF can also cause reduction of FVIII levels [5]. Type 3 VWD is the rarest and most severe type due to virtual absence of VWF and very low levels of FVIII, another protein involved in blood clotting. Hemophilia A is another type of genetic bleeding disorder characterized by deficiency in clotting FVIII, usually affecting males. Type 3 VWD can be difficult to diagnose due to its rarity. Symptoms, hemostatic challenge and bleeding history may become more apparent with increasing age. Since type 3 VWD also exhibits very low levels of FVIII resembles hemophilia A and it can be misdiagnosed if based on FVIII levels only.