von Willebrand disease update: diagnostic and treatment dilemmas.

Although von Willebrand disease (VWD) is now well-described, many facets of diagnosis and management continue to be debated. The diagnosis of type 1 disease can be difficult but recent genetic analyses help to distinguish many factors which can influence von Willebrand factor (VWF) levels and bleeding phenotype. Type 2 disease (functional abnormalities) includes a particularly interesting group of disorders with faulty binding between VWF and FVIIIC (Normandy) where treatment methods need careful consideration. Type 3 VWD is the most severe form of VWD and a new international study is underway to examine the use of prophylaxis.