Acquired von Willebrand syndrome--report of 10 cases and review of the literature.

Acquired von Willebrand syndrome (AvWS) is a rare bleeding disorder with clinical and laboratory features closely resembling hereditary von Willebrand disease (vWD), arising in previously haemostatically normal individuals. We present a retrospective review of 10 cases with AvWS diagnosed over 17 years. The severity of the bleeding tendency varied from mild to severe forms. Multimers electrophoresis showed that 8/10 patients had a normal pattern similar to type 1 vWD, 1/10 had a type 2A vWD pattern (with absence of high and intermediate molecular weight multimers) and 1/10 had a type 3 vWD pattern. An inhibitor screen was performed in 6/10 patients and autoantibodies against von Willebrand factor were found in only two cases. The underlying cause/associated conditions were identified in 8/10 patients. Treatment of the bleeding diathesis was successfully achieved with desmopressin or clotting factor concentrates. Resolution of underlying hypothyroidism (in two cases) and multiple myeloma (in one case) led to normalization of the coagulation parameters. The report on this cohort of 10 patients with AvWS illustrates the complexity of AvWS and its multifactorial aetiology. A brief review of the recent literature on AvWS is also presented, with emphasis on the current opinions in pathogenesis and treatment. Acquired von Willebrand syndrome (AvWS) is an acquired bleeding disorder, characterized by a phenotype similar to the inherited von Willebrand disease (vWD), with a prolonged bleeding time and low plasma levels of factor VIII - von Willebrand factor (vWF) measurements. It occurs in patients with no family history of vWD, who present with recent onset of bleeding symptoms. AvWS appears to be associated mainly with lymphoproliferative disorders, immunological conditions and neoplasia. AvWS is a rare condition and it is difficult to conduct prospective studies, therefore it is important to document the experience with such cases. The aim of this paper is first, to report 10 cases of AvWS identified at our Haemophilia Centre during the past 17 years. Second, to present a brief review of the recent literature on AvWS - outlining the salient features, associated disorders, mechanisms of acquisition and the available options of treatment.