Test Code VWDPKG von Willebrand Disease Panel

Specimen Type

Blood

Container

Three light blue top tubes, 3.2% sodium citrate

Preferred Volume

5.4 mL

Offsite Collection Instructions

Whole blood sample must arrive in the laboratory within three hours of specimen collection.

If transport time exceeds three hours, follow centrifugation instructions:

Samples must be centrifuged at >1500 x g for 10 minutes at room temperature.
Carefully remove the plasma from the cells using a plastic transfer pipette avoiding the buffy coat.
Aliquot removed plasma into 6 plastic tubes containing a minimum of 500 uL of specimen in each tube.
The plasma samples must then be frozen at -20ºC.
Once solidly frozen, they must be shipped on dry ice. Samples that have thawed in transit will be rejected.

Note: For clients who do not have access to dry ice DO NOT freeze the specimen. Follow the centrifugation instructions and send fresh plasma or send whole blood sample. It now becomes vital that the specimen arrives in the lab within three hours of collection.

UCMC Collection Instructions

Specimens may be collected and sent to the laboratory at any time.
Tests can be added on to an existing order up to 4 hours following the time of blood draw.

Availability

Please see “Test Includes” information above.

Turnaround Time

3-4 days

STAT Availability

Not Available

Test Methodology

Factor VIII Coagulant Activity (FA8): Clotting
vWF, Antigenic (VWAG): Immuno-turbidimetric (latex immuno assay)
vWF, Risto Cofactor (GPIb Binding) Actinity (VWF): Agglutination
vWF, Collagen Binding Activity (VWFCBA): ELISA

Additional Information

This package currently assesses both von Willebrand Factor (vWF) antigenic level and functional attributes. Functional attributes include an assessment of vWF interaction with platelets (assayed as ristocetin cofactor actinity), interaction with collagen (assayed as collagen binding activity), and interaction with factor VIII (assayed as circulating factor VIII activity, each of which is also orderable individually if preferred.
If required for diagnosis by the pathologist, send-out testing for Multimeric Analysis will also be performed. As appropriate, recommendations for further specialized testing such as ristocetin-induced platelet aggregation or DNA analysis may also be made in individual cases, but the performance of such testing will require additional orders (and in the case of ristocetin-induced platelet aggregation, a separate blood draw on the day of testing).

All 3.2% sodium citrate light blue top tubes require a ratio of 9 parts blood to 1 part anticoagulant (example: a 3.0 mL tube requires 2.7 mL blood added to 0.3 mL of anticoagulant).

CPT Code

85240, 85246, 85245, 83520

Test Includes

Factor VIII Coagulant Activity (FA8). Test performed 7 days a week from 8:00 am to 10:30 pm. Samples received in the laboratory after 10:30 pm will be run the next morning.

vWF, Antigenic Activity (VWAG). Test performed 7 days a week from 8:00 am to 10:30 pm. Samples received in the laboratory after 10:30 pm will be run the next morning.

vWF, Risto Cofactor (GPIb Binding) Actinity (VWF). Test run Monday – Friday, 8:00 am to 2:00 pm.

vWF, Collagen Binding Activity (VWFCBA). Test performed twice a week (Tuesdays and Thursdays). Sample must be received in the lab before 9:00 am to be included in the run.

Pathologist interpretation of abnormal results.
Note: von Willebrand Factor Multimeric Analysis will also be included if required by pathologist for diagnosis.

Reference Range

Factor VIII Coagulant Activity (FA8): 57-152%
vWF, Antigenic Activity (VWAG): 55-200%
vWF, Risto Cofactor (GPIb Binding) Actinity (VWF): 55-165%
vWF, Collagen Binding Activity (VWFCBA): 46-159%

Minimum Volume