Third Åland islands conference on vonWillebrand disease, 26–28September 2012: meeting report

Abstract

Summary The first meeting of international specialists in the field of von Willebrand disease (VWD) was held in the Åland islands in 1998 where Erik von Willebrand had first observed a bleeding disorder in some members of a family from Föglö and a summary of the meeting was published in 1999. The second meeting was held in 2010 and a report of the meeting was published in 2012. Topics covered included progress in understanding of VWD over the last 50 years; multimers; classification of VWD; pharmacokinetics and laboratory assays; genetics; treating the paediatric patient; prophylaxis; geriatrics; gene therapy and treatment guidelines. This third meeting held over 3 days covered the structure and function of von Willebrand factor (VWF); type 1 VWD, the most common form of the disease; a lifespan of pharmacokinetics in VWD; detecting inhibitors in VWD patients; and special challenges in understanding and treating the female VWD patient.

Safety and efficacy of a von Willebrand factor/factor VIII concentrate (Wilate®): a single centre experience

“…In an attempt to control for inter‐individual clustering of pharmacokinetic profiles, data were averaged per patient (summary measure) to give a more precise estimate of these parameters . Our findings with regard to recovery, however, are similar to those seen in more controlled studies .…”

Evaluation of an automated method for measuring von Willebrand factor activity in clinical samples without ristocetin

“…Other adaptations have included using immunoturbidimetric or chemiluminescent end‐points to quantitate VWF binding to immobilized glycoprotein (GP) Ibα instead of measuring the agglutination of target platelets . All ristocetin‐dependent estimates of VWF activity have a limitation : common VWF polymorphisms (e.g., D1472H), which are not associated with increased bleeding, reduce ristocetin‐dependent binding of VWF to GPIbα, resulting in lower than expected levels of VWF activity relative to VWF antigen (VWF:Ag) . While VWF activity can also be assessed by collagen binding methods, such assays do not evaluate VWF binding to GPIbα, which is altered in many forms of VWD .…”

Thalidomide for treatment of gastrointestinal bleedings due to angiodysplasia: a case report in acquired von Willebrand syndrome and review of the literature

“…Endothelial VWF has recently been identified as a negative modulator of VEGF‐dependent angiogenesis and angiogenesis has shown to be increased in VWF deficiency . However, these findings do not entirely explain the association between AVWS and angiodysplasia, as it seems unlikely that endothelial VWF is also affected in patients with AVWS . VWF high molecular weight multimers (HMWM) are probably also involved in the pathogenesis of VWD‐associated angiodysplasia, because most cases are associated with VWD subtypes lacking these HMWM .…”