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von Willebrand Factor Multimer Analysis, Plasma
MessageSendout, Mayo test cod: VWFMS
Test Code
LAB1111
Alias/See Also
Polymers, Von Willebrand Factor
VWF Mult Anal
Von Willebrand Protein Polymers SDS Gel, Plasma
VWFMS
VWF Mult Anal
Von Willebrand Protein Polymers SDS Gel, Plasma
VWFMS
CPT Codes
85247
Preferred Specimen
1 mL plasma from a light blue (sodium citrate) tube
Patient Preparation
1. Fasting is preferred.
2. Specimen should be collected prior to coagulation factor replacement therapy.
Minimum Volume
0.5 mL
Instructions
1. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.
2. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
3. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C or, ideally, below -40 degrees 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.
2. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
3. Freeze plasma immediately (no longer than 4 hours after collection) at -20 degrees C or, ideally, below -40 degrees 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.
Transport Container
Plastic vial
Transport Temperature
Frozen
Specimen Stability
Frozen: 42 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis: Reject
Gross lipemia: Reject
Gross icterus: Reject
Gross lipemia: Reject
Gross icterus: Reject
Methodology
Agarose Gel Electrophoresis/Infrared Dye-Labeled Antibody Detection
FDA Status
Approved
Setup Schedule
Monday through Thursday
Report Available
7-14 days
Limitations
Von Willebrand factor (VWF) multimer analysis is not useful if the following tests are normal:
-F8A / Coagulation Factor VIII Activity Assay, Plasma
-RIST / Ristocetin Cofactor, Plasma
-VWACT / von Willebrand Factor Activity, Plasma
-VWAG / von Willebrand Factor Antigen, Plasma
Or when:
-The VWF ristocetin cofactor:vWF antigen ratio is greater than or equal to 0.7
-The vWF activity:vWF antigen ratio is greater than or equal to 0.8
-F8A / Coagulation Factor VIII Activity Assay, Plasma
-RIST / Ristocetin Cofactor, Plasma
-VWACT / von Willebrand Factor Activity, Plasma
-VWAG / von Willebrand Factor Antigen, Plasma
Or when:
-The VWF ristocetin cofactor:vWF antigen ratio is greater than or equal to 0.7
-The vWF activity:vWF antigen ratio is greater than or equal to 0.8
Reference Range
Included with report
Clinical Significance
Resolving discrepancies when results of complementary laboratory tests (eg, F8A / Coagulation Factor VIII Activity Assay, Plasma; VWACT / von Willebrand Factor Activity, Plasma; and VWAG / von Willebrand Factor Antigen, Plasma) are abnormally low or discordant
Subtyping von Willebrand disease (VWD) (primarily identify variants of type 2 VWD)
Aiding in determining appropriate treatment
Identifying variants of type 2 VWD that have fewer of the largest multimers, have unusually large multimers, or have qualitatively abnormal "bands" that indicate an abnormal von Willebrand factor structure
Subtyping von Willebrand disease (VWD) (primarily identify variants of type 2 VWD)
Aiding in determining appropriate treatment
Identifying variants of type 2 VWD that have fewer of the largest multimers, have unusually large multimers, or have qualitatively abnormal "bands" that indicate an abnormal von Willebrand factor structure
Performing Laboratory
Mayo Clinic Laboratories, Rochester, Minnesota
Additional Information
von Willebrand Factor Multimer Analysis, Plasma
