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Test Code
CF8A
Test Name
Chromogenic Factor VIII, Activity
CPT Codes
85240
Expected Turnaround Time
2 - 6 days
Clinical Utility

Preferred test in patients with Lupus anticoagulant, on heparin or direct thrombin inhibitors, or on Factor VIII concentrates.
Specimen and Container Info

Specimen Type: Citrated Platelet-Poor Plasma

  

Collection Container: Light Blue Top (Sodium Citrate)

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect a light blue top (sodium citrate) tube via venipuncture.
Processing and Submission Instructions

Platelet-Poor Plasma Processing Instructions

  1. Perform platelet poor plasma processing procedure.
  2. Transfer 1 mL of platelet poor plasma to a clear aliquot tube (screw cap) and freeze.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Room Temperature

8 hours

Refrigerated

8 hours

Frozen

21 days
Causes for Rejection
  • Hemolysis
Methodology
Chromogenic Assay
Reference Intervals

See patient report.

Limitations

Storage of whole blood at refrigerated temperatures prior to processing may lead to cryoprecipitate formation and falsely low Factor VIII.
Reference Lab
Quest Diagnostics Nichols Institute
Testing Schedule
Routine, 2 times per week
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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