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Test Code
VIIIP
Test Name
Factor VIII Inhibitor Panel
CPT Codes
85240, 85335
Included Tests
  • FVIII Activity
  • Factor VIII, Inhibitor
Expected Turnaround Time
2 - 5 days
Clinical Utility

The presence of alloantibodies against factor VIII activity is a complication of treatment in hemophilia A, while the presence of autoantibodies may develop spontaneously in patients with acquired Factor VIII-C deficiency. The presence of Factor VIII inhibitor may lead to the neutralization (inactivation) of transfused or endogenous Factor VIII activity. The detection and magnitude of Factor VIII inhibitor is of great importance in the care of these patients. Factor VIII inhibitor Chromogenic assay provides a quick method for the detection of Factor VIII inhibitor with less sample volume.
Specimen and Container Info

Specimen Type: Platelet-Poor Plasma

  

Collection Container: Light Blue Top (Sodium Citrate)

Desired Specimen Volume: 4 mL
Collection Instructions
  1. Collect 3 light blue top (sodium citrate) tubes via venipuncture.
  2. Fill entire tubes with whole blood.
Processing and Submission Instructions

Platelet-Poor Plasma Processing Instructions

  1. Perform platelet-poor plasma processing procedure.
  2. Transfer 4 mL of platelet-poor plasma into a clear aliquot tube (screw cap).
  3. Please submit a separate, frozen aliquot tube for each special coagulation assay ordered.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Frozen

14 days
Methodology
Chromogenic | Photometric Clot Detection
Reference Intervals

See patient report.
Alternate Names
  • FVIII Bethesda Inhibitor
  • Factor VIII Inactivity
  • Inhibitor APTT
  • Factor 8 Inhibitor Evaluation
Reference Lab
Quest Diagnostics Nichols Institute
Testing Schedule
Routine, 3 times per week
Reflex Tests
NIJME
What triggers the reflex testing
If Factor VIII Inhibitor, Chromogenic Screen is Positive, then Nijmegen Assay will be performed at an additional charge.
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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