Von Willebrand Factor Collagen Binding

Test Code

VONCB

Alias/See Also

vWF Collagen Binding Assay
vWF: CBA

Quest Code
10924

CPT Codes
83520

Preferred Specimen

1 mL plasma collected in a 3.2% sodium citrate (light blue-top) tube, transferred to a plastic screw-cap vial

Minimum Volume

0.5 mL

Instructions

Please submit a separate, frozen vial for each special coagulation assay ordered.
Centrifuge light blue-top tube 15 minutes at approx. 1500 x 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 aliquoted tube containing plasma for and additional 15 minutes. Transfer platelet-poor plasma into a new plastic vial and freeze within 60 minutes of collection. Plasma must be free of platelets (<10,000/mcL).

Transport Temperature

Frozen

Specimen Stability

Room temperature: 24 hours
Refrigerated: 24 hours
Frozen: 21 days

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

Hemolysis
Lipemia
Icteric specimen
Received room temperature or refrigerated

Methodology
Enzyme Linked Immunosorbent Immunoassay (ELISA)

This test was performed using a kit that has not been cleared or approved by the FDA. The analytical performance characteristics of this test have been determined by Quest Diagnostics. This test should not be used for diagnosis without confirmation by other medically established means.

Setup Schedule

Monday, Wednesday Night

Report Available

3 days

Clinical Significance

The Collagen Binding Assay (vWF:CBA) is a test procedure that quantifies the binding of vWF to collagen. Collagen binding of vWF is associated with the functionally more important HMW forms of vWF. Therefore, vWF:CBA may correlate more closely with vWF function and bleeding problems than vWF antigen assay (vWF: Ag) which measures total vWF multimers. When used in conjunction with the vWF: Ag assay, vWF:CBA can be used to differentiate between vWD type 1 and type 2 (A and B subtypes) by calculating a ratio of the two assay results (ratio = vWF:CBA/vWFAg).

Performing Laboratory
Quest Diagnostics Nichols Institute
San Juan Capistrano, CA

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.