Interpretation

D-dimer values less than or equal to500 ng/mL fibrinogen-equivalent units (FEU) are normal. Within the reportable normal range (220-500 ng/mL FEU), measured values may reflect the activation state of the procoagulant and fibrinolytic systems, but the clinical utility of such quantitation is not established.

A normal D-dimer result (≤500 ng/mL FEU) has a negative predictive value of approximately 95% for the exclusion of acute pulmonary embolism (PE) or deep vein thrombosis when there is low or moderate pretest PE probability.

Increased D-dimer values are abnormal but do not indicate a specific disease state. D-dimer values may be increased as a result of:

-Clinical or subclinical intravascular coagulation and fibrinolysis (ICF)/disseminated intravascular coagulopathy (DIC).

-Other conditions associated with increased activation of the procoagulant and fibrinolytic mechanisms such as recent surgery, active or recent bleeding, hematomas, trauma, or thromboembolism.

-Association with pregnancy, liver disease, inflammation, malignancy or hypercoagulable (procoagulant) states.

The degree of D-dimer increase does not definitely correlate with the clinical severity of associated disease states.