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Updated: Jul 6, 2026
08:01
The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well
Published on: February 27, 2026
[Seventy years later: prothrombin time revisited].
Guido Reber1, Françoise Boehlen
1Unite d'hémostase, Service d'angiologie et hémostase, HUG, 1211 Geneve 14. guido.reber@hcuge.ch
Revue Medicale Suisse
|April 5, 2008
Summary
The prothrombin time (PT) test is crucial in hematology labs. Standardization efforts, like the International Normalized Ratio (INR) for oral anticoagulation, aim to improve consistency for patients with liver disease.
Area of Science:
- Hematology
- Clinical Chemistry
- Coagulation Diagnostics
Context:
- The prothrombin time (PT) test, introduced in 1935, is a cornerstone of hemostasis laboratory diagnostics.
- Variability in thromboplastin reagents (tissue factor origin, purity, phospholipids) leads to differing sensitivities in detecting coagulation factor deficiencies.
- Current PT result reporting lacks standardization for non-anticoagulated patients, varying by laboratory.
Purpose:
- To highlight the challenges in standardizing prothrombin time (PT) testing.
- To discuss the impact of reagent variability on PT assay sensitivity.
- To advocate for improved standardization of PT results, particularly for patients with hepatic disease.
Summary:
- The prothrombin time (PT) test, widely used in hemostasis, exhibits variability due to thromboplastin reagent composition.
- While the International Normalized Ratio (INR) has standardized PT monitoring for oral anticoagulation, non-anticoagulated patient results remain inconsistent.
- Standardization for PT assays in patients with hepatic disease is needed to improve diagnostic accuracy and comparability.
Impact:
- Improved consistency in PT test results across different laboratories.
- Enhanced diagnostic accuracy for coagulation disorders, especially in patients with liver disease.
- Facilitation of more reliable treatment monitoring and clinical decision-making in hemostasis.
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