Both authors contributed equally to this study.
ORIGINAL ARTICLE von Willebrand disease (VWD)
Screening for von Willebrand disease: contribution of an automated assay for von Willebrand factor activity
Article first published online: 28 SEP 2011
© 2011 Blackwell Publishing Ltd
Volume 18, Issue 3, pages e158–e163, May 2012
How to Cite
LASNE, D., DEY, C., DAUTZENBERG, M.-D., CHERQAOUI, Z., MONGE, F., AOUBA, A., TORCHET, M.-F., GELOEN, D., LANDAIS, P. and ROTHSCHILD, C. (2012), Screening for von Willebrand disease: contribution of an automated assay for von Willebrand factor activity. Haemophilia, 18: e158–e163. doi: 10.1111/j.1365-2516.2011.02662.x
- Issue published online: 25 APR 2012
- Article first published online: 28 SEP 2011
- Accepted after revision 30 August 2011
- ristocetin cofactor activity;
- von Willebrand disease;
- von Willebrand factor activity
Summary. Measuring von Willebrand factor (VWF) activity is essential to the diagnosis of von Willebrand disease (VWD). The VWF activity is usually assessed based on measurement of the ristocetin cofactor (VWF:RCo). However, that test is technically challenging and has high intra- and inter-assay variabilities. The HemosIL VWF activity (VWF:AC) is a fully automated assay, recently proposed as a good alternative to VWF:RCo for VWD diagnosis. This study was undertaken to assess this new method. First, the analytical performance of VWF:AC on an automated coagulo-meter (ACLTop) was determined, and then this new method was compared with VWF:RCo and the platelet function analyzer (PFA100) for 160 patients referred for VWD screening. The VWF:AC achieved acceptable precision with within-run and between-run coefficients of variation ranging from 2.3% to 14.1%, and linearity from 10% to 100%. Despite some marked differences between VWF:AC and VWF:RCo for 10 plasmas tested, their agreement for VWD diagnosis was good. The VWF:AC had sensitivity similar to that of PFA100 (close to 100%), but better specificity (97.7% vs. 66% or 60%, depending on the cartridge used). The good analytical performance, and the sensitivity and specificity of VWF:AC to detect VWF deficiency renders it a suitable method for VWD screening. Our findings support VWF:AC use for the diagnostic work-up of VWD, paying close attention to concomitant clinical signs and bleeding score, as recommended for VWD.