ARUP's Laboratory Test Directory

APC Resistance Profile : 0030127

Mnemonic: APC RST

Ordering Recommendation: Acceptable initial test to detect activated protein C resistance due to a factor V Leiden mutation. Preferred test is APC Resistance Profile with Reflex to Factor V Leiden (0030192). However, Factor V Leiden (F5) R506Q Mutation (0097720) is the preferred initial test for individuals with supratherapeutic concentrations of heparin, direct thrombin inhibitors, extreme factor V deficiency, or lupus anticoagulants with markedly prolonged baseline clotting times.
Methodology: Clotting
Performed: Mon-Fri
Reported: 1-4 days
Specimen Required: Collect: Lt. blue (sodium citrate). Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines.

Specimen Preparation: Transfer 1.5 mL platelet-poor plasma to an ARUP Standard Transport Tube. (Min: 1 mL)

Storage/Transport Temperature: Frozen.

Unacceptable Conditions: Serum. Non-frozen or hemolyzed specimens.

Stability (collection to initiation of testing): Ambient: 4 hours; Refrigerated: Unacceptable; Frozen at -20°C: 3 months; Frozen at -70°C: 6 months
Reference Interval:
Effective February 21, 2012

2.0 or greater
Interpretive Data: Ratios less than 2.00 suggest APC resistance. This method uses factor V deficient plasma; therefore, APC resistance due to a nonfactor V mutation will not be detected. Extreme factor V deficiency may cause abnormal ratio.
CPT Code(s): 85307
Cross References: Activated Protein C Resistance (APCR) (APC Resistance Profile), APCR (APC Resistance Profile), Factor V Leiden Functional Assay (APC Resistance Profile), Protein C Resistance (APC Resistance Profile)