Ristocetin Cofactor, Plasma  Email this article           Printer friendly page

Primary Name Ristocetin Cofactor
Synonym Von Willebrand factor activity
Synonym --
Contraction VWF Activity
Contraction VWF:RCo
Contraction --
UAB Procedure Number 2500350
CPT Code 85245
Specimen Collect one (1) blue-stopper tube (3.2% sodium citrate), filled to specified volume. Do not underfill or overfill.

Specimen Management Centrifuge blue-stopper tube within one (1) hour of collection, separate plasma and test or quick-freeze at -70°C.
Specimen Accepted Daily including weekends
Test Performed Once a week - Call lab at 205-934-8650 for information.
Available Stat? No.
Description The ristocetin cofactor test is the primary assay used to diagnose von Willebrand disease as it measures plasma von Willebrand factor activity.
Reference Interval 50-166%
Follow-up Test *The ristocetin cofactor test is usually performed together with the von Willebrand factor antigen and the factor VIII activity assay, forming the von Willebrand disease profile. 
Associated With Bleeding disorders
Associated With Von Willebrand disease
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