what is von
Definition. Von Willebrand disease is a condition that can cause extended or excessive bleeding. The condition is most often inherited but in rare cases may develop later in life.The cause of von Willebrand disease is a deficiency in or impairment of a protein called von Willebrand factor, an important component in your blood-clotting process.In general, it takes longer for people with von Willebrand disease to form clots and stop bleeding when they're cut.he condition is most often inherited but in rare cases may develop later in life. The cause of von Willebrand disease is a deficiency in or impairment of a protein called von Willebrand factor, an important component in your blood-clotting process.