Tissue Thromboplastin Inhibition (TTI)

Test Code

92534

Alias/See Also

Dilute Prothrombin Time

CPT Codes
85705<br /> <strong>This test is not available for California patient testing.</strong>

Preferred Specimen

2 mL frozen platelet-poor plasma collected in a 4.5 mL 3.2% sodium citrate (blue-top) tube

Minimum Volume

2 mL

Instructions

Separate plasma within one hour of collection and freeze at -70° C or less. Ship on dry ice.

Transport Container

Plastic screw-cap vial

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen (-70° C): 90 days

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

Received room temperature • Received refrigerated

Methodology
Photometric, prothrombin time performed with dilute thromboplastin

FDA Status

Setup Schedule

Set up: Mon-Fri; Report available: 2 days

Reference Range

TTI 1:50	0.7-1.3 Ratio
TTI 1:500	0.7-1.3 Ratio

Clinical Significance

Detect lupus-like anticoagulants. Prolonged prothrombin times invalidate the tissue thromboplastin inhibition test.

Performing Laboratory
Vitalant Speciality Laboratories & Therapeutics Coagulation Laboratory
3636 Boulevard of Allies
Pittsburg, PA 15213-4306

Last Updated: September 9, 2019

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.