Search All

Lab Test Dictionary

von Willebrand Comprehensive Panel 2 (15540)

Synonyms

vWF

Specimen Type

Plasma

Performing Lab

Quest Diagnostics San Juan Capistrano

Epic ID

LAB4384

Collection Information

Specimen Required

(four-five) 1.8 mL or (three-four) 2.7 mL Blood

Container Type

Light Blue (Sodium Citrate)

Processing Information - Lab Use Only

Transport Temperature

Frozen-Only

Specimen Stability

Room Temp: Unacceptable; Refrigerated: Unacceptable; Frozen: 14 Days

Test Volume Required

1 mL (x4) Platelet-Poor Plasma

Minimum Test Volume

0.75 mL (x4) Platelet-Poor Plasma

Processing Instructions

Platelet Poor Plasma: Centrifuge light blue-top tube 15 minutes at approx. 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 send frozen.

Included Tests

Partial Thromboplastic Time, Activated; Factor VIII Activity, Clotting; von Willebrand Factor Antigen; Ristocetin Cofactor; von Willebrand Factor Collagen Binding Assay; von Willebrand Antigen Multimeric Analysis

Comments

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