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Laboratory Medicine

Test catalogue

von Willebrand Factor: Antigen

Test Name

von Willebrand Factor: Antigen (vWF Antigen)

Blue Tube Specimen Type / Requirements

Container Type = Blue Tube (Sodium Citrate)

Minimum Volume = Full draw

9:1 Ratio (9 parts blood to 1 part anticoagulant)

Specimen Handling

Collection Instructions: Must indicate anticoagulant status to avoid delay. A Hematology consult is REQUIRED for inpatient samples (except for patients in 2 Donnelly). Referred-in patients and outpatients can be tested without a Hematology consult.

Write your initials, date and time of collection on the collection label.

Transportation: In/Outpatients: Send whole citrated blood at room temperature as soon as possible. Referred-in: Send frozen citrated plasma on dry ice. All samples must be sent to the Core Laboratory.

Stability: Specimens are stable for 4 hours post collection at room temperature. Specimens which are not tested within 4 hours can be double-spun to remove the citrated plasma. The citrated plasma is stable at -20°C for up to two weeks or -70°C for up to six months.

Sample Rejection Criteria: Clotted sample, grossly hemolyzed samples, Unlabeled or samples with insufficient quantity will be rejected.

Required Documentation

Turnaround Time (TAT)

7 days

Test Utilization

Reference Value

Blood Group O: 0.45 - 1.45 U/mL

Other Blood Groups: 0.50 - 2.00 U/mL

Test Code

FAG8

Methodology

Latex Immunoassay

Testing Location

SMH-Special Coagulation

Other Information

Last Updated: June 06, 2019