What test is a global marker of coagulation activation and measures fibrin degradation products?

The D-dimer test serves as a global marker of coagulation activation and is specifically designed to measure fibrin degradation products in the bloodstream. When blood coagulation occurs due to injury or a pathological condition, fibrinogen is converted into fibrin, forming a clot. As the clot is subsequently broken down, fibrin is cleaved into various degradation products, including D-dimer.

Elevated levels of D-dimer in the blood can indicate increased fibrinolysis, which occurs in conditions like deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation (DIC). Therefore, the test’s ability to reflect the state of coagulation and breakdown of fibrin makes it highly relevant for diagnosing and monitoring various thrombotic disorders.

In contrast, tests such as Activated Partial Thromboplastin Time (APTT) and Prothrombin Time (PT) are more focused on specific aspects of the coagulation cascade rather than serving as a global marker. The Factor V Leiden test is specifically a genetic test looking for a mutation that increases the risk of thrombosis, rather than assessing overall coagulation activation.