Test Code AVWPR von Willebrand Disease Profile, Plasma
Ordering Guidance
Multiple coagulation profile tests are available. See Coagulation Profile Comparison for testing that is performed with each profile.
Shipping Instructions
Send all 3 aliquots in the same shipping container.
Necessary Information
1. If priority specimen, mark request form, give reason, and request a call-back.
2. Note if patient is currently receiving anticoagulant treatment (eg, heparin, Coumadin [warfarin]).
Specimen Required
Specimen Type: Platelet-poor plasma
Patient Preparation:
1. Patient should not be receiving anticoagulant treatment (eg, warfarin, heparin). Treatment with heparin causes false-positive results of in vitro coagulation testing for lupus anticoagulant. Coumadin (warfarin) treatment may impair ability to detect the more subtle varieties of lupus-like anticoagulants.
2. Patient should also not be receiving fibrinolytic agents (streptokinase, urokinase, tissue plasminogen activator[ tPA]).
3. It is best to perform this study pretransfusion if possible. If patient has been recently transfused, wait at least 48 hours after transfusion to collect the specimen.
Collection Container/Tube: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Plastic vials
Specimen Volume: 3 mL in 3 plastic vials, each containing 1 mL
Collection Instructions:
1. Specimen must be collected prior to factor replacement therapy.
2. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing.
3. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.
4. Aliquot plasma (1-2 mL per aliquot) into 3 separate plastic vials, leaving 0.25 mL in the bottom of centrifuged vial.
5. Freeze plasma immediately (no longer than 4 hours after collection) at -20° C or, ideally, -40° C or below.
Additional Information:
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.
Specimen Type
Plasma Na CitSpecimen Minimum Volume
2 Plastic vials, each containing 1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Na Cit | Frozen | 14 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Report Available
2 to 12 daysSpecimen Retention Time
7 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
85240-Coagulation factor VIII assay
85246-von Willebrand factor antigen
85397-von Willebrand factor activity
85245-von Willebrand factor ristocetin cofactor activity (if appropriate)
85247-von Willebrand factor multimer (if appropriate)
85335-Bethesda titer (if appropriate)
85335-Coagulation factor VIII inhibitor screen (if appropriate)
85390-26-Special coagulation interpretation (if appropriate)
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
F8IS | Coag Factor VIII Assay Inhib Scrn,P | No | No |
AVWPQ | von Willebrand Disease Interp | No | No |
VWFMP | von Willebrand Factor Multimer, P | Yes, (order VWFMS) | No |
RIST | Ristocetin Cofactor, P | No | No |
8BETH | FVIII Bethesda Units, P | No | No |