Does Von Willebrand Disease Affect PTT?

Does Von Willebrand Disease Affect PTT? Von Willebrand disease (VWD) is a hereditary deficiency of von Willebrand factor (VWF), which causes platelet dysfunction. Bleeding tendency Which lab test will be affected in case of von Willebrand disease? It measures primarily the clotting ability of factors I (1), II (2), V (5), VII (7), and X