Biomarkers of Inflammation and Oxidation: D-dimer

Optimal Takeaways

D-dimer is a compound produced from the breakdown of a blood clot and reflects the degree of blood clotting present. It can reflect intravascular thrombosis and helps monitor anticoagulation therapy and rule out DVT or pulmonary embolism. Levels can also increase with inflammation, heart disease, infection, hemorrhage, stroke, and liver or kidney disease. High levels are usually considered pathological though levels can increase in pregnancy. Low to non-detectable levels are considered normal; therefore, elevations should be investigated.

Standard Range: 0.00 - 0.50 ug/mL FEU (0.00 - 500.00 ng/mL FEU)

The ODX Range: 0.00 - 0.50 ug/mL FEU (0.00 - 500.00 ng/mL FEU)

Low D-dimer levels suggest the absence of thrombosis, DVT, and pulmonary embolism (Pagana 2021).

High D-dimer levels will be seen in deep vein thrombosis (DVT), pulmonary embolism, disseminated intravascular coagulation (DIC), arterial thromboembolism, sickle cell anemia, surgery, pregnancy, and malignancy. Levels may increase with elevated rheumatoid factors (Pagana 2021).

Higher D-dimer may also be seen with infection, peripheral arteriopathy, aneurism, congestive heart failure, ischemic cardiomyopathy, aortic dissection, ARDS, liver or kidney disease, recent surgery, hemorrhage, stroke, and inflammatory bowel disease (Tripodi 2011). Elevations may be associated with inflammation, cardiovascular disease (Johnson 2019), and COVID-19 mortality (Zhang 2020).

Overview

D-dimer is a fibrin degradation fragment that results from the breakdown of a blood clot. D-dimer indicates how much fibrin degradation is occurring and is reflective of the degree of blood clotting taking place. Monitoring D-dimer helps monitor and restart anticoagulation therapy (Pagana 2021).

D-dimer may be used as a marker of coagulation, fibrinolysis, and, ultimately, intravascular thrombosis. It is beneficial for ruling out pulmonary embolism or DVT. D-dimer may be measured in fibrinogen equivalent units (FEU), which is two times the value of D-dimer units (DDU) (Johnson 2019).

Evaluation of D-dimer levels in COVID-19 patients was instrumental in predicting in-hospital mortality. A retrospective review confirmed that patients with a D-dimer of 2 ug/mL or higher had significantly greater (fourfold increase) mortality. Researchers recommended employing D-dimer as an early marker of prognosis in COVID-19 patients (Zhang 2020).

References

Johnson, Eric D et al. “The D-dimer assay.” American journal of hematology vol. 94,7 (2019): 833-839. doi:10.1002/ajh.25482

Pagana, Kathleen Deska, et al. Mosby's Diagnostic and Laboratory Test Reference. 15th ed., Mosby, 2021.

Tripodi, Armando. “D-dimer testing in laboratory practice.” Clinical chemistry vol. 57,9 (2011): 1256-62. doi:10.1373/clinchem.2011.166249

Zhang, Litao et al. “D-dimer levels on admission to predict in-hospital mortality in patients with Covid-19.” Journal of thrombosis and haemostasis : JTH vol. 18,6 (2020): 1324-1329. doi:10.1111/jth.14859