Validation of a rapid test (VWF-LIA) for the quantitative determination of von Willebrand factor antigen in type 1 von Willebrand disease diagnosis within the European multicenter study MCMDM-1VWD.

Abstract

BACKGROUND:

Accurate measurement of von Willebrand factor (VWF) is a critical requirement for the diagnosis of von Willebrand disease (VWD).

AIM OF THE STUDY:

To evaluate the diagnostic efficiency of a rapid quantitative test for the measurement of VWF antigen (VWF:Ag) in type 1 VWD.

PATIENTS AND METHODS:

VWF:Ag was measured with an ELISA in a robotic instrument, as a reference method, and with a fully automated latex-immunoassay (LIA) on an ACL 9000 analyser in 1,716 subjects enrolled within the Molecular and Clinical Markers for Diagnosis and Management of Type 1 von Willebrand Disease (MCMDM-1VWD) Study. Among these subjects, 1,049 were healthy controls, 281 healthy family members and 386 affected members from 127 European families with type 1 VWD.

RESULTS:

The assay linearity range was 10-125 IU/dL for LIA (R2=0.99) and 5-133 IU/dL for ELISA (R2=0.99). The inter-assay CV for low VWF levels (approximately 30 IU/dL) was 2% for the LIA test and 8.7 % for ELISA. The sensitivity for detection of type 1 VWD affected members was 86% and the specificity 91% for LIA, 87% and 90% for ELISA. A receiver-operator (ROC) analysis disclosed only a marginal difference between the two tests, LIA having a slightly greater area under the curve (0.94 vs. 0.93, p=0.03).

CONCLUSION:

VWF:Ag LIA compared well to standard ELISA in this large population of patients and controls, showing better CV. However the lower detection limit for the VWF:Ag LIA compared to the VWF:Ag ELISA means that the LIA assay is less good at discriminating between type 3 VWD and moderate type 1 VWD.

• Authors: G Castaman, A Tosetto, A Cappelletti, A Goodeve, A B Federici, J Batlle, D Meyer, J Goudemand, J C J Eikenboom, R Schneppenheim, U Budde, J Ingerslev, S Lethagen, F Hill, I R Peake, F Rodeghiero
• Journal: Thrombosis research (Thromb Res) Vol. 126 Issue 3 Pg. 227-31 (Sep 2010) ISSN: 1879-2472 [Electronic] United States
• PMID: 20650506 (Publication Type: Comparative Study, Journal Article, Multicenter Study, Validation Study)
• Copyright: Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Chemical References

• Biomarkers
• von Willebrand Factor

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Automation, Laboratory
• Biomarkers (blood)
• Case-Control Studies
• Child
• Child, Preschool
• Enzyme-Linked Immunosorbent Assay (standards)
• Europe
• Humans
• Latex Fixation Tests (standards)
• Middle Aged
• Observer Variation
• Predictive Value of Tests
• ROC Curve
• Reference Standards
• Reproducibility of Results
• Robotics
• Sensitivity and Specificity
• Young Adult
• von Willebrand Disease, Type 1 (blood, diagnosis)
• von Willebrand Factor (analysis)