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Test Code
FIXIH
Test Name
Factor IX Activity and Human Inhibitor
CPT Codes
85250, 85335
Included Tests
  • Factor IX Activity, Clotting
  • Factor IX Inhibitor
Expected Turnaround Time
3 - 11 days
Clinical Utility

Factor IX Human Inhibitor provides a quantitative determination of inhibitors. This aids in developing treatment strategies for patients with hemophilia.
Specimen and Container Info

Specimen Type: Platelet poor plasma

Collection Container: Light Blue Top (Sodium Citrate)

Desired Specimen Volume: 4 mL (2 mL per tube)
Collection Instructions
  1. Collect 2 light blue top sodium citrate tubes via venipuncture.
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 two clear aliquot tubes (2 mL in each aliquot tube).
Transport Instructions

Transport to the laboratory frozen.
Stability Requirements

Frozen

14 days
Methodology
Clot Based Assay | Photometric Clot Detection
Reference Intervals

See patient report
Alternate Names
  • Factor IX Inhibitor Panel
  • Bethesda Titer
Reference Lab
Quest Diagnostics Nichols Institute
Testing Schedule
Routine, 1 time 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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