Test Code Billings Clinic: 7636 Mayo: VWFMS von Willebrand Factor Multimer Analysis, Plasma
Reporting Name
von Willebrand Factor Multimer, PPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
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
Method Name
Agarose Gel Electrophoresis/Infrared Dye-Labeled Antibody Detection
Ordering Guidance
Coagulation testing is highly complex, often requiring the performance of multiple assays and correlation with clinical information. For that reason, we suggest ordering AVWPR / von Willebrand Disease Profile, Plasma.
Additional Testing Requirements
VWACT / von Willebrand Factor Activity, Plasma and VWAG / von Willebrand Factor Antigen, Plasma are requested but not required before performing this test. If already assayed, submit results. If no results are included, submit separate specimens for the above assays following specimen requirements for each test.
Specimen Required
Specimen Type: Platelet-poor plasma
Patient Preparation:
1. Fasting is preferred.
2. Specimen should be collected prior to coagulation factor replacement therapy.
Collection Container/Tube: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing.
2. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.
3. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
4. 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
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Na Cit | Frozen | 42 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Reference Values
An interpretive report will be provided.
Interpretation
The plasma von Willebrand factor (VWF) multimer analysis is a qualitative visual assessment of the size spectrum and the banding pattern of VWF multimers.
Day(s) Performed
Monday through Thursday
Report Available
7 to 14 daysTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
85247
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
VWFMS | von Willebrand Factor Multimer, P | 48595-3 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
603851 | von Willebrand Factor Multimer, P | No LOINC Needed |
603855 | VWF Multimer Interpretation | 48595-3 |
Forms
1. Coagulation Patient Information (T675)
2. If not ordering electronically, complete, print, and send a Coagulation Test Request (T753) with the specimen.