Methodology
Clotting/Microlatex Particle-Mediated Immunoassay/Quantitative Immunoturbidimetry
Synonyms
Factor VIII, Vactor VIII Activity; GPIbM; von Willebrand Factor (VWF) Activity; von Willebrand Factor A
Specimen Type
Plasma
Performing Lab
ARUP
Epic ID
Other Reference Test
Lab Test Days
Daily
Standard TAT
1-11 Days
Collection Information
Specimen Required
(two-four) 1.8 mL or (two-three) 2.7 mL Blood
Container Type
Sodium Citrate (Blue-Top) Tube
Processing Information - Lab Use Only
Transport Temperature
Frozen-Only
Specimen Stability
Room Temp: 4 Hours; Refrigerated: Unacceptable; Frozen: 3 Months (preferred)
Rejection Criteria
Serum; EDTA Plasma; Clotted; Hemolyzed
Test Volume Required
3 mL Platelet-Poor Plasma
Minimum Test Volume
1.5 mL Platelet-Poor Plasma
Processing Instructions
Complete an ARUP requisition and submit with specimens frozen. Send with daily Apollo Courier.
Included Tests
Factor VIII Activity; von Willebrand Factor, Antigen; von Willebrand Factor, Activity (GPIbM); von Willebrand Factor Multimers (0092281) added automatically but reported separate due to longer turnaround time.
CPT Codes
85240, 85246, 85397; 85247 (not genetic)
Revised
2/13/26
Initials
IM