Semin Thromb Hemost 2022; 48(06): 690-699
DOI: 10.1055/s-0042-1749591
Review Article

Analysis of College of American Pathologists von Willebrand Factor Proficiency Testing Program

Eric Salazar
1   Department of Pathology and Laboratory Medicine, UT Health San Antonio, San Antonio, Texas
,
Thomas A. Long
2   Department of Biostatistics, College of American Pathologists, Northfield, Illinois
,
Kristi Johnson Smock
3   Department of Pathology and ARUP Laboratories, University of Utah, Salt Lake City, Utah
,
Geoffrey D. Wool
4   Department of Pathology, University of Chicago, Chicago, Illinois
,
Marian Rollins-Raval
5   Department of Pathology, University of New Mexico, Albuquerque, New Mexico
,
Dong Chen
6   Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
,
Neil Selwyn Harris
7   Department of Pathology, University of Florida, Gainesville, Florida
,
Clarence W. Chan
8   Department of Pathology, University of Chicago Medical Center, Chicago, Illinois
,
John D. Olson
1   Department of Pathology and Laboratory Medicine, UT Health San Antonio, San Antonio, Texas
,
Huy P. Pham
9   Seattle Apheresis Collection Center, National Marrow Donor Program (NMDP)Seattle, Washington
,
Jacob Ritter
1   Department of Pathology and Laboratory Medicine, UT Health San Antonio, San Antonio, Texas
,
David Unold
10   Department of Pathology and Laboratory Medicine, University of California Davis Medical Center, Sacramento, California
,
Amanda Matzke VanSandt
11   Department of Pathology and Laboratory Medicine, Oregon Health & Science University, Portland, Oregon
,
Andrew Jackson Goodwin IV
12   Department of Pathology, University of Vermont Medical Center, Burlington, Vermont
› Institutsangaben
Preview

Abstract

Von Willebrand factor (VWF) level and/or function is altered in von Willebrand disease (VWD), the most common heritable bleeding disorder worldwide. Laboratory assessment of VWF is continually evolving. Historically, the primary method for the assessment of VWF platelet-binding activity was the ristocetin cofactor assay (VWF:RCo). Contemporary alternative measures of VWF platelet-binding activity include VWF:GPIbR (recombinant; using ristocetin), VWF:GPIbM (recombinant; gain-of-function mutant), and monoclonal antibody. Recently, the American Society of Hematology, International Society on Thrombosis and Haemostasis, National Hemophilia Foundation, and World Federation of Hemophilia collaboration issued guidelines recommending the use of newer assays of VWF platelet-binding activity (VWF: GPIbM, VWF: GPIbR) over VWF:RCo, given known limitations of the VWF:RCo assay. Despite this recommendation, the newer VWF:GPIbM and VWF:GPIbR assays are not United States Food and Drug Administration cleared, limiting their availability in the United States. We sought to assess assay utilization trends, agreement of VWF testing methods, and imprecision of VWF testing (based on assigned sample type) from the College of American Pathologists Proficiency Testing Surveys. The analysis confirms that, while VWF antigen testing has low imprecision, the various VWF activity assays have significant interassay variability, with VWF:RCo showing greater imprecision than the newer GPIb-binding assays. The overall trends in assay utilization reflect the barriers to complete compliance with modern VWD diagnostic guidelines in North America.



Publikationsverlauf

Artikel online veröffentlicht:
02. September 2022

© 2022. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA