Factor X Activity, Chromogenic

Test Code

CPT Codes

Preferred Specimen
1 mL frozen plasma collected in 3.2% sodium citrate (light blue-top) tube

Minimum Volume
0.5 mL

Platelet-poor plasma: Centrifuge light blue 15 minutes at approximately 1500X g within 60 minutes of collection. Using a plastic pipette, remove plasma, taking care to avoid the WBC/platelet buffy layer and place into a plastic vial. Centrifuge a second time and transfer platelet-poor plasma into a new plastic vial. Plasma must be free of platelets(<10,000/mcL). Freeze immediately and ship on dry ice.

Transport Temperature

Specimen Stability
Room temperature: 2 hours
Refrigerted: 8 hours
Frozen: 21 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Received room temperature • Received refrigerated • Gross Hemolysis • Icterus • Lipemia


Setup Schedule
Set up: Mon-Sat; Report available: 1-3 days

Reference Range
73-158 % activity
Therapeutic reference range: 11-42 % activity

Clinical Significance
To assess Factor X chromogenic activity in plasma. This assay may help in monitoring OAC patients with prolonged pro-times such as Warfarin patients with lupus inhibitor.

Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA
33608 Ortega Highway
San Juan Capistrano, CA 92675-2042

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.