Despite many attempts by experts on von Willebrand Factor (VWF) pathophysiology who have tried for the last 25 years to improve clinical and laboratory assessments of Von Willebrand Disease (VWD), VWD awareness remains poor in most countries because lab testing is complex and costly. In contrast to hemophilia A, which can be identified only by prolonged activated partial thromboplastin time (APTT) with low levels of FVIII, at least 5-8 laboratory tests are always necessary to diagnose VWD types. Indeed, complex diagnostic approaches for VWD as recommended in the ASH-ISTH-NHF-WFH-2021 Guidelines are only available in a few hemophilia Centers, located at High-Income Countries (HIC). On behalf of the Italian Association of Hemophilia Centers (AICE), we have identified the minimal test requirements for the clinical and laboratory diagnosis of different VWD types and proposed a simplified diagnostic approach to be used at all Italian Centers. Such a simplified diagnostic approach has been already assessed in a pilot study named CREWILACT. By using only baseline PD-VWFact/Ag, VWF:CB/Ag ratios VWD3 (n=14), VWD1 (n=39), VWD2A (n=21), VWD2M (n=13) could be identified while VWD1C (n=6), VWD2B (n=5), VWD2N (n=4) and AVWS (n=10), could be confirmed only after DDAVP trial when FVIII/VWF:Ag and platelet counts could be also tested. Members of the Working Group on VWD affiliated with AICE and with Italian Society on Thrombosis and Hemostasis (SISET) have decided to propose the continuation of this pilot study in a prospective clinical trial entitled STADIAWILD (DeSmopressin Clinical Trial At Diagnosis for Management of Inherited and Acquired von WILlebrand Factor Defects). Main objective of STADIAWILD is to validate the simplified diagnostic approach using automatic tests before and after DDAVP trial in mild-moderate patients with inherited and acquired VWF defects (at least 300) enrolled at European Centers. Since biological response can be identified during DDAVP trial at diagnosis, VWD patients with positive response will be observed prospectively for efficacy and safety of DDAVP used to manage spontaneous bleeding episodes or to prevent bleeding during minor or major surgery. Clinical efficacy, safety, and costs of DDAVP therapy will be also compared with those of VWD patients treated with VWF concentrates
Learning Objectives:
On behalf of the Italian Association of Hemophilia Centers (AICE), we have identified the minimal test requirements for the clinical and laboratory diagnosis of different VWD types and proposed a simplified diagnostic approach to be used at all Italian Centers.
