Abstract
The American Society of Hematology–International Society on Thrombosis and Haemostasis–National
Hemophilia Foundation–World Federation of Hemophilia 2021 International Guidelines
(IGL) on von Willebrand disease (VWD) have pointed out many challenges, mainly in
the diagnostic approach of VWD patients. To determine the impact of these IGL on the
current clinical and laboratory diagnosis of Italian VWD patients, we have recently
conducted a survey among 43 centers affiliated with the Italian Association of Hemophilia
Centers (AICE). Directors and colleagues responsible for the management of VWD patients
were invited to report in a detailed questionnaire how IGL recommendations about the
assessment of the specific activities of von Willebrand Factor (VWF) could be applied
at their local sites. Results from such a survey showed that bleeding assessment tools,
VWF antigen, and factor VIII procoagulant are currently in use in all centers. The
automated assays for platelet-dependent VWF activity with or without ristocetin described
in IGL have been used since 2021 in 37/43 (86%) centers. Among other laboratory tests,
VWF collagen binding, ristocetin-induced platelet agglutination, multimeric analysis,
VWF propeptide, VWF:FVIII binding assay were available in 49, 63, 26, 7, and 28% of
AICE, respectively. Analyses of VWF gene defects are available only at 3/43 (7%) centers.
Desmopressin (DDAVP) infusion trials at diagnosis, with measurements of VWF activities
at 1 and 4 hours post-DDAVP, is currently performed at 38/43 (88%) centers. Based
on this information, a simplified clinical diagnosis using a few automated tests before
and after DDAVP has been proposed. Such a diagnostic approach will be validated prospectively
in a large cohort of Italian VWD patients.
Keywords
von Willebrand factor - bleeding assessment tools - VWF activities - laboratory diagnosis
of VWD - biological response to DDAVP
