Evaluation of Two Automated Methods for Measurement of the Ristocetin Cofactor Activity of von Willebrand Factor

Connie H. Miller; S. Jean Platt; Christine Daniele; Daniel Kaczor

doi:10.1055/s-0037-1613154

Thrombosis and Haemostasis, Inhaltsverzeichnis

Thromb Haemost 2002; 88(01): 56-59
DOI: 10.1055/s-0037-1613154

Review Article

Schattauer GmbH

Evaluation of Two Automated Methods for Measurement of the Ristocetin Cofactor Activity of von Willebrand Factor

Autor*innen

Connie H. Miller

¹Hematologic Diseases Branch, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
S. Jean Platt

¹Hematologic Diseases Branch, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
Christine Daniele

²Diagnostica Stago Inc., Parsippany, New Jersey, USA
Daniel Kaczor

²Diagnostica Stago Inc., Parsippany, New Jersey, USA

Abstract

Summary

We have evaluated two automated methods for measuring ristocetin cofactor activity (VWF:RCo) on an automated coagulation analyzer (STAR^®, Diagnostica Stago Inc., Parsippany, NJ). A modification of the BC von Willebrand Reagent method (Dade Behring Inc., Newark, Delaware) was compared with a standard method using a platelet aggregometer, and an in-house automated method was developed using commercially available components. The STAR^® measures the change in optical density (OD) caused by agglutination of platelets. Change in OD was linear for plasma dilutions between .25 and .04 U/mL. Coefficient of variation compared favorably with that of the standard method. In 123 normal women, the correlation coefficient (r) = .905. In menorrhagia cases, r = .901. In 20 VWD patients, r = .93. The CDC in-house method was compared to the BC Reagent method in 79 additional menorrhagia cases, with r = .94. The automated methods produced results equivalent or superior to those of traditional methods of measuring VWF:RCo.

Keywords

von Willebrand factor - ristocetin cofactor - methods

Volltext

Referenzen

References
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