Test Code LAB757 von Willebrand Factor Antigen, Plasma
Methodology
Immunoturbidimetric Assay
Literature References:
HemosIL von Willebrand Factor Antigen package insert issued 02/2010, Instrumentation Laboratory.
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Specimen Requirements
Specimen Type: Plasma
Container/Tube: Light-blue top (citrate)
Specimen Volume: 1 Full tube
Specimen Minimum Volume: Full tube
Collection Instructions:
- Draw a discard blue top tube prior to drawing a light-blue top (citrated) tube if using a Winged Infusion Set. Discard tube should be under filled and discarded.
- Clotted blood or an insufficient specimen is not acceptable.
- Avoid phlebotomy techniques which cause hemolysis and heparin contamination.
- Follow nursing policy on volume of blood to discard prior to collecting blood from indwelling heparinized catheters.
Analyte Stability:
4 hours at 18° C to 24° C.
Platelet-free plasma can be frozen at -20 for transport on dry ice up to 72 hours
or stored 6 months at -70° C.
Additional Information: If the patient is a hospital patient and the hematocrit is >55%, call Barnes-Jewish Hematology Laboratory at 314-362-5203 for instructions.
Specimen Transport Temperature
Ambient Yes/Refrigerate NO/Frozen Yes
Reference Values
55%-200%
Literature References:
1. Sukhu K, Martin PG, Cross L, Keeling DM, Giangrande PL. Evaluation of the von Willebrand factor antigen assay using an immuno-turbidimetric method automated on the MDA 180 coagulometer. Clin Lab Haematol 2000;22(1):29-32.
2. Sadler JE. A revised classification of von Willebrand disease. Thrombosis and haemostatis. FK Schattauer Verlagsgesellschaft mbH (Stuttgart), 1994;71;520-5.
Day(s) Test Set Up
Monday, Wednesday, and Friday
Cut-off time: 0700
Turnaround Time:
STAT: not available
Routine: results available the day of testing
Test Classification and CPT Coding
85246
Additional Information
For BJH Laboratory Use Only
Analyte Stability:
4 hours at 18° C to 24° C.
Platelet-free plasma can be frozen at -20 for transport on dry ice up to 72 hours
or stored 6 months at -70° C.
Laboratory Processing Instructions:
Test performed in BJH Core Lab.
LOINC Code Information
Name LOINC Code
vWF Antigen 6012-9