How is von Willebrand disease diagnosed?
Dr. Jürgen Patzke
Diagnosis of von Willebrand disease (VWD) is a complex process that can require several medical visits and laboratory assessments. In addition to the
patient’s clinical history and bleeding symptoms, the results of certain
laboratory tests need to be evaluated.
What is von Willebrand disease?
Von Willebrand disease is the most frequently inherited human bleeding disorder, which is characterized by a reduction or dysfunction of von Willebrand factor (VWF), a protein in the blood that acts as a key player in hemostasis. A deficiency or dysfunction of von Willebrand factor can lead to severe bleeding that is hard to stop.
VWF testing guidelines
Which laboratory tests are used in the diagnosis of von Willebrand disease?
According to the ASH ISTH NHF WFH 2021 guidelines on the diagnosis of von Willebrand disease, the first level diagnostic panel should include:
- VWF antigen test
- Platelet-dependent VWF activity test
- FVIII activity test
After this first line of tests, additional testing may include:
- Collagen binding-activity
- VWF multimer assessments
- Factor VIII-binding test
- Genetic testing
VWF activity assay panel glossary
Activity assays are part of the recommended assay panel and measure the function of VWF. They help identify qualitative and quantitiative defects of the protein and are therefore a crucial part of the initial testing panel for VWD.
The table below lists different assay principles (adapted from Bodo et al., 20151 and Higgins and Goodwin, 20192) used in commercially available assays.
Recommended by the ASH ISTH NHF WFH 2021 guidelines on the diagnosis of von Willebrand disease as first line assays are VWF:RCo, VWF:GPIbM or VWF:GPIbR.
Unique assay principle
How is VWF activity measured with the INNOVANCE VWF Ac assay?
The INNOVANCE® VWF Ac assay from Siemens Healthineers uses a mutated version of the platelet-binding receptor, the so-called GPIb receptor, of the von Willebrand factor molecule, which is bound to latex particles. This mutated receptor binds to the VWF molecule spontaneously, which allows particle agglutination to occur without ristocetin.
On the analyzer, Reagent III, containing the GPIbα fragment, is mixed with Reagent II, Owren's Veronal Buffer, and the patient’s plasma sample. VWF contained in the sample binds to the gain-of-function GPIbα fragment without support from shear stress, ristocetin, or any other agent. After 120 seconds of incubation, Reagent I, which contains the microparticles, is added as the starting reagent (See figure below). The binding of the microparticles to the VWF/GPIbα complex is measured as an increase in turbidity, which is caused by particle agglutination.
The INNOVANCE VWF Ac assay's unique technology enables increased precision and is less susceptible to effects of certain polymorphism variants.
Assay performance
INNOVANCE VWF Ac assay performance
Over the past 10 years, several studies have utilized the assay and several benefits have been noted:
- High analytical sensitivity1 and precision3
- Good comparability/ correlation to VWF:RCo assay4
- Improved detection of functional abnormalities5
- Insensitivity to polymorphism P.P1467S and P.D1472H6
In the ASH ISTH NHF WFH 2021 guidelines on the diagnosis of von Willebrand disease, the panel suggests newer assays to measure VWF platelet-binding activity (e.g., VWF:GPIbM, VWF:GPIbR) rather than VWF:RCo due to their:
- Lower coefficient of variation and higher reproducibility compared to VWF:RCo
- Concern that D1472H sequence variant may lead to overdiagnosis of VWD by the VWF:RCo method
Literature Compendium: A review of guidelines and utility in diagnosis
(INNOVANCE VWF Ac assay)
Download a review of current guidelines and recommendations for von Willebrand testing
- Current recommendations and guidelines for von Willebrand testing
- Reviews of von Willebrand disease testing
- Studies reviewing the performance of INNOVANCE VWF Ac assay
...and much more!
About Dr. Jürgen Patzke
Watch scientific webinars and educational videos about VWD diagnostics and physiological backgrounds
Credits for VWF-3D graphic:
PDB: 1SQ0
Dumas JJ, Kumar R, McDonagh T, Sullivan F, Stahl ML, Somers WS, Mosyak L. Crystal structure of the complex of the wild-type von Willebrand factor A1 domain and glycoprotein Ib alpha at 2.6 angstrom resolution. 2004. doi: 10.2210/pdb1SQ0/pdb
Dumas JJ, Kumar R, McDonagh T, Sullivan F, Stahl ML, Somers WS, Mosyak L. Crystal structure of the wild-type von Willebrand factor A1-glycoprotein Ibalpha complex reveals conformation differences with a complex bearing von Willebrand disease mutations. J Biol Chem. 2004;279:23327-34. doi: 10.1074/jbc.M401659200
Bodó I, et al. JTH. 2015. doi.org/10.1111/jth.12964
Castaman G, et al. Expert opinion on orphan drugs. 2019. doi.org/10.1080/21678707.2019.1609352
Geisen U, et al. Thromb Res. 2014. doi.org/10.1016/j.thromres.2014.04.033
Szederjesi A., et al. JTH. 2018. doi.org/10.1111/jth.14206
Higgins RA, Goodwin AJ. Am J Hematol. 2019. doi.org/10.1002/ajh.25393
Favaloro EJ, et al. Thromb Res. 2018. doi.org/10.1016/j.thromres.2018.04.015
Graf L, et al. Int J Lab Hematol. 2014. doi.org/10.1111/ijlh.12218
Szederjesi A, et al. JTH. 2018. doi.org/10.1111/jth.14206
de Maistre E, et al. Thromb Haemost. 2014. doi.org/10.1160/TH14-02-0108
Favaloro EJ, et al. Thromb Res. 2016b. doi.org/10.1016/j.thromres.2015.12.010
Florin, C., et al. Ann Biol Clin. 2016. doi.org/10.1684/abc.2016.1145
Graf L, et al. Int J Lab Hematol. 2014. doi.org/10.1111/ijlh.12218
Higgins RA, Goodwin AJ. Am J Hematol. 2019. doi.org/10.1002/ajh.25393
Lassalle F, et al. Poster presented at ISTH congress. 2020. academy.isth.org/isth/2020/milan/296705/fanny.lassalle.the.vwf.variant.d1472h.affects.vwf.binding.to.ristocetin.in.html
Moonla C, et al. Clin Appl Throm Haemost. 2019. doi.org/10.1177/1076029619866916
Szederjesi, A, et al. JTH. 2018. doi.org/10.1111/jth.14206
Szederjesi, A., et al. JTH. 2020. doi.org/10.1111/jth.14971
Vangenechten, I., et al. JTH. 2018. doi.org/10.1111/jth.14145
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