Methods, precision, and analytical sensitivity of a novel low‐plasma‐volume assay of fibrinolytic capacity utilizing the euglobulin fraction.

Introduction Methods Results Conclusion Fibrinolysis is a critical aspect of the hemostatic system, with assessment of fibrinolytic potential being critical to predict bleeding and clotting risk. We describe the method for a novel low‐plasma‐volume assay of fibrinolytic capacity utilizing the euglobulin fraction (the “modified mini‐euglobulin clot lysis assay [ECLA]”), its analytic sensitivity to alterations in key fibrinolytic substrates/regulators, and its initial applications in acute and convalescent disease cohorts.The modified mini‐ECLA requires 50 μL of plasma, a maximal read time of 3 h (with most results available within 60 min), and is entirely performed in a 96‐well microplate. Assay measurements were obtained in a variety of commercial control and deficient plasmas representing clinically relevant hypo‐ and hyperfibrinolytic states, and in three distinct adolescent cohorts with acute or convalescent illness: critically ill, following endotracheal intubation; acute COVID‐19‐related illness; and ambulatory, 3 months following a venous thromboembolic event.In 100% and 75% deficient plasmas, hypofibrinolysis for plasminogen‐deficient, fibrinolysis for alpha‐2‐antiplasmin‐deficient, and hyperfibrinolysis for plasminogen activator inhibitor‐1‐deficient plasmas were observed.The modified mini‐ECLA Clot Lysis Time Ratio (“CLTR”) demonstrated moderate‐strength correlations with the Clot Formation and Lysis (CloFAL) assay, is analytically sensitive to altered fibrinolytic states in vitro, and correlates with clinical outcomes in preliminarily‐studied patient populations. [ABSTRACT FROM AUTHOR]