Thrombin Clotting Time with Reflex to Mixing Study [14459X]

Test Code

CPT Codes

If the Thrombin Clotting Time is >23 seconds, then Mixing Studies will be performed at an additional charge (CPT codes(s): 85675).

Preferred Specimen
1 mL plasma collected in each of two separate light blue 3.2% sodium citrate tubes

Minimum Volume
0.5 mL (x2)

Platelet-poor plasma: Centrifuge light blue-top tube 15 minutes at approx. 1500 x 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.

If the Thrombin Clotting Time is abnormal, test will reflex to the mixing study at an additional charge.

Transport Container
Plastic screw-cap vial

Transport Temperature

Specimen Stability
Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 30 days

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

Clot Detection

Setup Schedule
Set up: Mon-Fri; Report available: Next day

Reference Range
Thrombin Clotting Time13-19 seconds

Clinical Significance
Thrombin Clotting Time - This test, also known as thrombin time, is useful for evaluating the presence of heparin and other direct thrombin inhibitor anticoagulants in specimens with prolonged coagulation studies. It is also used to aid in the diagnosis of congenital and acquired disorders of fibrinogen.

Anticoagulant interference: Expected impact by therapeutic levels (potential interference depends upon drug concentration): Vitamin K antagonists (eg. warfarin): no effect; Heparin (UFH or LMWH): prolonged; Dabigatran or Argatroban (Direct Thrombin Inhibitors): prolonged; Rivaroxaban, Apixaban, Edoxaban (Factor Xa Inhibitors): no effect.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

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.