Von Willebrand Panel

Test Code

902533

CPT Codes
85240, 85245, 85246<br /> Restricted Client Code

Includes

347 Factor VIII Activity, Clotting
4919 Von Willebrand Factor Antigen
4459 Ristocetin Cofactor

Preferred Specimen

3 mL platelet-poor plasma collected in 3.2% sodium citrate (light blue-top) tube

Minimum Volume

1.5 mL

Instructions

Platelet-poor plasma - Centrifuge light blue-top tube for 15 minutes at approximately 1500 g within 60 minutes of collection. Using a plastic pipette, remove plasma, taking care to avoid the WBC/platelet buffy layer and place into a plastic vial. Centrifuge a second time and transfer platelet-poor plasma into a new plastic vial. Plasma must be free of platelets (<10,000/mcL). Freeze immediately and ship on dry ice.

Note: Storage of whole blood at refrigerated temperatures prior to processing may lead to cryoprecipitate formation and falsely low Factor VIII and von Willebrand Factor studies.

Transport Container

Plastic vial

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolysis • Lipemia • Received thawed

Methodology
See individual tests

Setup Schedule

Set up and Report available: See individual tests

Reference Range

See Laboratory Report

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.