Factor V Leiden Scr (APCR)

Test Code

APCR

Alias/See Also

FV LEIDEN SCR

CPT Codes
85307

Preferred Specimen

1 Blue/ 1Lav

Minimum Volume

Blue top must be filled to Minimum Fill Indicator Line on tube.

Other Acceptable Specimens

none

Instructions

Outreach clients should double-spin the blue top plasma, remove the plasma from the RBC button, and freeze in a polypropylene tube, and send the lavender top as whole blood at room temperature.

Transport Container

PO, LAV

Transport Temperature

PO frozen, LAV ambient

Specimen Stability

Blue - 4 hours ambient; Plasma - 6 months frozen; LAV - 7 days refrigerated

Methodology
Clotting Activation

Setup Schedule

Monday, Wednesday & Friday (dayshift)

Report Available

Upon Completion of Analysis

Limitations

Protein C values <50% may give low ratios. Initial Coumadin treatment may give low results.

Reference Range

< or = 1.4 (Suggestive of Factor V Leiden defect)

> or = 2.1 (Negative for Factor V Leiden defect)

Always run APCR (screening test) before the Molecular FVL. Values < or = 1.4 should be confirmed with genetic testing for Factor V Leiden. Values >2.1 require no further testing.

Clinical Significance

The Factor V Leiden assay is a simple clotting test system intended for screening of resistance to Activated Protein C in plasma from individuals with the Factor V Leiden defect. It can also be performed on plasma from patients on stabilized oral anticoagulant or on heparin therapy.

Activated Protein C Resistance is associated with a point mutation in the Factor V gene, Factor V Leiden. This mutation slows the inactivation of factor Va by APC causing a hypercoaguable state. The presence of Factor V Leiden is the most common cause of inherited thromobophilia, accounting for 20% to 50%.

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.