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Related Experiment Video

Updated: May 12, 2026

Assessment of the Anticoagulant and Anti-inflammatory Properties of Endothelial Cells Using 3D Cell Culture and Non-anticoagulated Whole Blood

Assessment of the Anticoagulant and Anti-inflammatory Properties of Endothelial Cells Using 3D Cell Culture and Non-anticoagulated Whole Blood

Published on: September 5, 2017

Kaolin clotting time.

Kottayam Radhakrishnan¹

¹Department of Clinical Haematology, Royal Children's Hospital, Melbourne, Australia.

Methods in Molecular Biology (Clifton, N.J.)

|April 3, 2013

Summary

The kaolin clotting time (KCT) detects lupus anticoagulants (LA) by omitting phospholipids. Sample quality is critical for accurate LA detection using this sensitive laboratory test.

Area of Science:

Hematology
Clinical Chemistry

Background:

The kaolin clotting time (KCT) is a sensitive laboratory assay.
It is a variant of the activated partial thromboplastin time (APTT) test.
KCT lacks added phospholipid, relying on intrinsic factors for activation.

Purpose of the Study:

To elucidate the mechanism and requirements of the kaolin clotting time (KCT) test.
To highlight the importance of sample quality in KCT for lupus anticoagulant (LA) detection.

Main Methods:

Utilizing kaolin as the sole activator.
Performing an activated partial thromboplastin time (APTT) assay without exogenous phospholipid.
Employing a confirmatory test with excess phospholipid.

Main Results:

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Thrombin generation in KCT is dependent on residual cell membranes and plasma lipids.
The absence of added phospholipid makes the test highly sensitive to sample quality.
A confirmatory test with excess phospholipid is necessary for accurate LA identification.

Conclusions:

The kaolin clotting time (KCT) is a valuable tool for lupus anticoagulant (LA) detection.
Strict control over sample quality is essential for reliable KCT results.
Confirmatory testing is crucial to validate LA presence identified by KCT.