ristocetin cofactor การใช้

• The ristocetin cofactor activity and loss of large vWF multimers are similar to vWD type 2B.
• Thus, the ristocetin cofactor activity depends only upon high-molecular multimers of the factor present in circulating plasma.
• The ristocetin cofactor activity is low when the patient's platelet-poor plasma is assayed against formalin-fixed, normal donor platelets.
• Thus, if the patient's platelet-poor plasma is used, the ristocetin cofactor assay will not agglutinate standardized platelets ( i . e ., pooled platelets from normal donors that are fixed in formalin ), similar to the other types of vWD.