VON WILLEBRAND FACTOR ANTIGEN

Test Code

VWB

Alias/See Also

VWF Ag

CPT Codes
85246

Preferred Specimen

Blue Tube (Sodium Citrate)

If a butterfly needle is use for collection, a NON-ADDITIVE discard tube must be drawn first

Patient Preparation
None

Minimum Volume

1 mL (Tube MUST be filled to nominal line for proper whole blood to anticoagulant ratio – see volume guides below)

Instructions

Gentle mix by inversion. Must be processed within 4 hours of collection. Separate and freeze plasma if unable to process within 4 hours.

Lab note: Refer to document below (Obtaining a Platelet-Poor Specimen)

Transport Container

Blue Tube

Transport Temperature

Room Temperature

Specimen Stability

15-25ºC (room temperature) up to 4 hours
-20ºC (frozen) plasma samples are stable

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

Serum
EDTA plasma
Clotted
Hemolysis
Collection tube underfilled or overfilled

Methodology
Microlatex Particle-Meditated Immunoassay

Setup Schedule

DAILY, DAY SIFT ONLY (8:00A - 3:00P)

Report Available

STAT: <60 minutes
Routine: <4 hours

Reference Range

43-120%

Performing Laboratory
Mount Sinai Hospital
Holy Cross Hospital

Additional Information
BD Vacutainer Blue Top Volume Guide
Greiner Vacutainer Blue Top Volume Guide
Obtaining A Platelet-Poor Specimen

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.