A 61-year-old female without prior history of bleeding experienced several symptomatic episodes of gastrointestinal bleeding in the last few years. A source of gastrointestinal bleeding could not be found although several tests of occult blood in the stool were positive. Diagnostically, a significant deficiency of von Willebrand factor could be found due to a shortened half-life of the von Willebrand factor. This acquired von Willebrand factor deficiency most likely can be explained by an immunological mechanism (e.g. antibodies against von Willebrand factor). Neither an immunosuppressive therapy with steroids nor cyclophosphamide could normalize the von Willebrand factor and the bleeding continued. Only tranexamic acid (inhibiting fibrinolysis) could at last stop the symptomatic episodes of gastrointestinal bleeding despite the fact of decreasing von Willebrand factor.