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Updated: Jun 22, 2026
08:01
The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well
Published on: February 27, 2026
Thrombin generation and bleeding in haemophilia A.
K E Brummel-Ziedins1, M F Whelihan, M Gissel
1Department of Biochemistry, University of Vermont, College of Medicine, Colchester, VT 05446, USA. kathleen.brummel@uvm.edu
Summary
Tissue factor-initiated thrombin generation maximum levels (MaxL) in whole blood predict bleeding risk in hemophilia A patients. This finding aids in understanding disease heterogeneity and assessing bleeding tendency.
Area of Science:
- Hematology
- Thrombosis and Hemostasis
Background:
- Haemophilia A exhibits significant clinical severity variability.
- Predicting bleeding risk in haemophilia A is crucial for patient management.
- Thrombin generation is a key indicator of hemostatic potential.
Purpose of the Study:
- To investigate if tissue factor (TF)-initiated thrombin generation profiles predict bleeding risk in haemophilia A.
- To correlate thrombin generation parameters with clinical bleeding scores in haemophilia A patients.
Main Methods:
- Studied 27 individuals with factor VIII deficiency (mild, moderate, severe).
- Assessed 5-year bleeding history to generate a clinical bleeding score.
- Measured TF-initiated thrombin generation (clot time, maximum level, maximum rate) in CTI-treated whole blood.
Main Results:
- Maximum thrombin level (MaxL) significantly differed between bleeding score groups (P < 0.001).
- Higher MaxL correlated with lower bleeding scores (lower bleeding tendency).
- Maximum thrombin rate (MaxR) showed a trend towards correlation with bleeding scores (P = 0.09).
Conclusions:
- The maximum level of thrombin generation in CTI-inhibited whole blood correlates with the bleeding phenotype in haemophilia A.
- Thrombin generation profiling may serve as a valuable tool for assessing bleeding risk in haemophilia A.
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