Test Code F25L Factor II (Prothrombin G20210A) and Factor V Leiden Genotype
Methodology
Please note: Factor II (Prothrombin G20210A) and Factor
V
Leiden mutation testing are both performed in this panel. The
tests
are not offered individually.
This test should only performed once in a patient’s
lifetime.
Methodology: Cepheid Xpert Hemosil Factor II and Factor
V
Assay
Polymerase
Chain Reaction (PCR) and Multiplexing
Micro-Chip Array
Technology,
Performing Laboratory
Bronson Laboratory Services-Microbiology
Specimen Requirements
Specimen Type: Whole blood
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Sodium citrate
Specimen Volume: Full tube
Specimen Minimum Volume: 500 ul
peripheral
blood drawn in an EDTA microtainer
Collection Instructions:
1. Invert several times to mix blood.
2. Send specimen in original tube.
Additional Information:
1. Molecular coagulation test requested must have its own
tube.
2. To avoid co-mingling and cross contamination: If
specimen is to be shared with another department, the
molecular testing must take an aliquot of the specimen first or
perform their testing prior to routing to additional testing
departments.
Reject Due To:
Hemolysis: Mild OK; Gross OK
Lipemia: Mild OK; Gross OK
Icterus: NA
Other: Green-top (heparin) tube; previously performed (this test
is
only performed once in a patient’s lifetime)
Specimen Transport Temperature
Stable 24 hours when stored at room temperature (22-28°
C)
Stable 15 days when stored at 2-8° C
Stable 3 months when stored at -20° C or -80° C
Reference Values
Negative
Note: Factor II (G20210A) and Factor V Leiden mutations are
present in 2% and 5% of the general population, respectively
Day(s) Test Set Up
Monday through Friday on day shift
Test Classification and CPT Coding
81240
81241
This test has been approved by the U.S. Food and Drug
Administration and is used per manufacturer’s
instructions.
Clinical Utility
Factor V Leiden is Useful for:
Direct mutation analysis should be reserved for patients
with
clinically suspected thrombophilia and:
- Activated protein C (APC)-resistance
proven or suspected by a
low APC-resistance ratio
-Family history of the factor V (FV Leiden) mutation
It may be appropriate to screen those women contemplating
oral
contraceptive use or pregnancy, with consideration of an
alternative form of contraceptive therapy or venous
thromboembolism
(VTE) prophylaxis during pregnancy or the
postpartum state for
women with FV Leiden allele
Knowledge of the FV Leiden allele status may alter
anticoagulation management of VTE
patients.
Factor II Prothombin is useful for:
Direct mutation analysis for the prothrombin (PT) G20210A
allele
in patients with documented venous thromboembolism, deep vein
thrombosis, or pulmonary embolism.