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Test ID AVWPR von Willebrand Disease Profile, Plasma


Advisory Information


Multiple coagulation profile tests are available. See Coagulation Profile Comparison in Special Instructions 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


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. If patient has been recently transfused, it is best to perform this study pretransfusion, if possible.

Specimen Type: Platelet-poor plasma

Collection Container/Tube: Light-blue top (3.2% sodium citrate)

Submission Container/Tube: 3 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 in Special Instructions.

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.

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.


Forms

Coagulation Patient Information (T675) in Special Instructions

Useful For

Detection of deficiency or abnormality of von Willebrand factor (VWF) and related deficiency of factor VIII coagulant activity

 

Subtyping von Willebrand disease (VWD) as type 1 (most common), type 2 variants (less common), or type 3 (rare)

 

This test is not useful for detection of hemophilia carriers.

Profile Information

Test ID Reporting Name Available Separately Always Performed
AVWPI von Willebrand Disease Tech Interp No Yes
F8A Coag Factor VIII Activity Assay, P Yes Yes
VWAG von Willebrand Factor Ag, P Yes Yes
VWACT von Willebrand Factor Activity, P Yes Yes

Testing Algorithm

Initial testing includes: coagulation factor VIII activity assay, von Willebrand factor (VWF) antigen, VWF activity and interpretation. 

 

If the factor VIII, VWF antigen, VWF activity, and  VWF activity:VWF antigen ratio are normal, then a computer-generated interpretive comment indicating no evidence of von Willebrand disease will be provided.

 

If VWF activity assay is less than 55% or VWF activity:VWF antigen ratio is abnormally increased, then VWF ristocetin cofactor activity assay will be performed at an additional charge.

 

If VWF antigen is less than 55%, the VWF activity is less than 55%, or the VWF activity:VWF antigen ratio is abnormally low, then VWF multimer analysis will be performed at an additional charge.

 

If any test results are abnormal, all results will be reviewed by a coagulation consultant and a von Willebrand Disease Interpretation will be provided at an additional charge.

 

See von Willebrand Disease Profile in Special Instructions.

Method Name

F8A: Optical Clot-Based

VWAG, VWACT: Latex Immunoassay (LIA)

Reporting Name

von Willebrand Disease Prof

Specimen Type

Plasma Na Cit

Specimen Minimum Volume

2 plastic vials each containing 1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Plasma Na Cit Frozen 14 days

Reference Values

An interpretive report will be provided.

Day(s) and Time(s) Performed

F8A: Monday through Friday

VWAG, VWACT: Monday through Saturday

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

See Individual Test IDs

CPT 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)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
AVWPR von Willebrand Disease Prof 48593-8

 

Result ID Test Result Name Result LOINC Value
F8A Coag Factor VIII Activity Assay, P 3209-4
VWAG von Willebrand Factor Ag, P 27816-8
AVWPI von Willebrand Disease Tech Interp 48595-3
VWACT von Willebrand Factor Activity, P 68324-3

NY State Approved

Yes

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