T-Tek

Assay Type
Fibrinogen Reagents
Description
Thrombin reagent with human thrombin for the Thrombin Time Test
Intended Use
The T-Tek thrombin time reagent is intended for use in the quantitative determination of Thrombin Time (TT) in citrated human plasma in the general patient population. T-Tek should be used in the clinical laboratory by qualified laboratory professionals. The test may be performed using manual methods or semi-automated or automated coagulation analyzers.
Uses
  • To rule out the presence of heparin (in conjunction with the Reptilase Time)
  • To detect qualitative abnormalities or quantitative deficiencies of fibrinogen
Ordering Information
Catalog # Product Kit Configuration Regulatory Classification Product Insert (PDF)
50-201 T-Tek 10 x 1 mL 510(k), CE LL-4517_E TTek
Principle of the Test

The active coagulation enzyme, thrombin, acts on soluble fibrinogen to convert it to insoluble fibrin. This reaction is manifested by the appearance of a visible fibrin clot. Any substance that interferes with this reaction, i.e. heparin or fibrin degradation products, may produce a prolonged thrombin clotting time. Low plasma fibrinogen levels as well as abnormal fibrinogen molecules seen in severe liver disease or as congenital abnormalities will also prolong the clotting time.

The Thrombin Time test is performed by adding 1 volume of Thrombin Time reagent to 1 volume of citrated plasma pre-warmed to 37C, and the time taken to detect the clot end point is recorded.

Reporting Units
The Thrombin Time is reported as the seconds to clot formation after the addition of the reagent. Each laboratory should determine a normal reference range. If a sample’s clot time is prolonged beyond the reference range the fibrinogen level or activity is low or thrombin inhibitors may be present.
Handbooks and Guidelines
  • Thrombin Time Assays, pages 219-220, in Lapasota et. al., The Clinical Hemostasis Handbook, Year Book Medical Publishers, 1989.  This handbook is no longer in print, but many pathologists have a copy.
  • Rogers G, Chapter 5 “Hemostasis Screening Assays”, in Laboratory Hemostasis: A Practical Guide for Pathologists, Bennet S et. al. editors, Springer 2007.
  • Krishnan J, Chapter 6, “Coagulation Testing”, in An Algorithmic Approach to Hemostasis Testing, Kottke‑Marchant ed., CAP Press, 2008.