Antibody-induced von W illebrand’s Disease: A Newly Defined Inhibitor Syndrome

  • William C. Maloney
  • Published 2005


A patient is described with clinical and did not interfere with the measurement of laboratory evidence of von Willebrand’s VIllA or inactivate VIlI F activity. The disease (VWD) in association with inhibitor was present in serum heated at lymphosarcoma. He consistently had a 56#{176}C for 30 mm, was present in a purifIed bleeding time of over 20 mm; factor IgG fraction of serum, and was precipiVlIl ,, VlllA , and Vlll ,w, under 20%; tated by anti-human IgG. The antibody and severe, diffuse hemorrhage. Followdid not interact directly with washed ing transfusion with cryoprecipitate, the platelets, but appeared to interact with patient had the expected rise in VIllA that portion of the factor VIII protein that and VIll ,,,, but no secondary increment in supports ristocetin aggregation (VIll p). VIIIAHF. The patient’s plasma contained an The data provide the first explanation for inhibitor which prevented aggregation of the pathophysiology of the acquired von normal platelets by ristocetin, but which Willebrand’s syndrome. V ON WILLEBRAND’S DISEASE (VWD) is usually inherited as an autosomal dominant trait and is characterized by a prolonged bleeding time and a moderate deficiency of factor VIII coagulant activity (VIIIAHF)*.I Unlike patients with hemophilia, patients with VWD also have a decreased level of the factor VIII-associated antigen (VIIIAGN), low platelet retention in glass bead columns, abnormal ristocetin-induced platelet aggregation, and poor adhesion of platelets to vascular subendothelium.25 These abnormalities in platelet function can usually be corrected in vitro by adding factor VIII-rich plasma fractions to the patient’s blood.6’7 This property ofthe factor VIII molecule has been called the von Willebrand factor (VIIIVWF). To date, the precise molecular nature and interrelation between the coagulant activity, the von Willebrand factor activity, and the antigen recognized by heterologous antisera have not been determined with certainty.8’2 A number of patients have also been described who have an acquired bleeding disorder that has similar clinical and laboratory features to inherited VWD.’319 In these patients, the levels of VIIIAGN were decreased and, in one

Cite this paper

@inproceedings{Maloney2005AntibodyinducedVW, title={Antibody-induced von W illebrand’s Disease: A Newly Defined Inhibitor Syndrome}, author={William C. Maloney}, year={2005} }