Recurrent Gastrointestinal Bleeding in a Middle-Aged Man

Acquired von Willebrand disease (avWD) arises because of mechanisms that destroy, decrease, absorb, or clear von Willebrand factor (vWF). A 59-year-old man presented with a 3-year history of recurrent gastrointestinal bleeding. Laboratory workup revealed a prolonged platelet function assay-100. The vWF antigen was decreased, and a low vWF immunofunctional activity/antigen ratio, low collagen binding/antigen ratio, and decreased intermediate and high molecular weight multimers were noted. The patient had no high-shear stress conditions, and an antibody-mediated process was suspected. A vWF mixing study showed complete correction of vWF activity, suggesting no direct functional inhibitor. The patient was given a bolus of vWF concentrate with serial measurements of vWF; the vWF half-life was 2.5 hours. The vWF propeptide/antigen ratio was 4:1, supporting a diagnosis of aVWD resulting from increased antibody-mediated vWF clearance. This case study emphasizes the laboratory’s role in the diagnosis and treatment of rare, overlooked acquired bleeding disorders. was 5.0 g/dL. Past medical history was significant for multiple recent hospitalizations and workup for gastrointestinal bleeding. He had numerous endoscopic evaluations, including 6 colonoscopies, 4 upper endoscopies, 2 gastrointestinal capsule studies, and a tagged red blood cell study in the past 3 years, all of which failed to identify a clear anatomic source of bleeding, although they did identify extensive diverticulosis and nonbleeding hemorrhoids. Past surgical history included a right hemicolectomy with ileocolonic anastomosis more than 3 years before presentation because of a tubulovillous adenoma without excessive bleeding. The patient denied significant bleeding in childhood or bleeding complications after previous medical interventions.