PTT-LA with Reflex to Hexagonal Phase Confirmation

Test Code

17408

CPT Codes
85730

Includes

If PTT-LA Screen is prolonged (>40 seconds), then Hexagonal Phase Confirmation will be performed at an additional charge (CPT code(s): 85598).

Preferred Specimen

1.5 mL frozen platelet-poor plasma collected in a 3.2% sodium citrate (light blue-top) tube

Minimum Volume

0.5 mL

Instructions

Please submit a separate, frozen vial for each special coagulation assay ordered. Draw blood in a light blue-top tube containing 3.2% sodium citrate, mix gently by inverting 3-4 times. Centrifuge 15 minutes at 1500 g within one hour 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(s). Freeze immediately and transport on dry ice.

Transport Container

Plastic vial

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolysis

Methodology
Clot Detection

Setup Schedule

Set up: Mon-Fri; Report available: 1-4 days

Reference Range

≤40 seconds

Clinical Significance

PTT-LA with Reflex to Hexagonal Phase Confirmation - The PTT-LA is a sensitive, but non-specific assay for Lupus anticoagulants (LA). The Hexagonal Phase confirm is a specific LA test. As international guidelines recommend a multi-test approach to LA detection due to antibody heterogeneity, a comprehensive panel is available (Lupus anticoagulant Comprehensive Evaluation). Lupus anticoagulant Comprehensive Evaluation includes the PTT-LA with reflex to Hexagonal Phase Confirm, plus the DRVVT pathway of testing.
Note: Target specific anticoagulant therapy (anti-Xa medications, direct thrombin inhibitors) may cause false positive results.

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.