Understanding the concept and value of D-dimers

Radiometer Medical India recently hosted a webinar, Understanding the concept and value of D-dimers. Garnering an overwhelming participation of critical care specialists, clinicians and laboratory professionals from India, and across the world.

Guillaume Galpy underscored the importance of D-dimer in the management of patients with suspected pulmonary embolism (PE) /deep venous thromboembolism (DVT) and how an elevated D-dimer can help in prognosis of COVID-19 patients.

Pulmonary embolism (PE) occurs when a blood clot breaks loose (embolus) and follows the bloodstream to the lungs where it gets stuck and blocks the blood passage causing shortness of breath, coughing, lung-related chest pain¹. Based on several researches and publications released lately, venous thromboembolism (VTE) is known to be frequently reported in COVID-19 cases. Such research works brought out the importance of laboratory testing in such situation. D-dimer is one such biomarker which when used in combination with clinical probability assessment, is used to rule out patients from risk of DVT or PE. Recommendations have been made to prevent and diagnose VTE by including VTE risk assessment scoring for all COVID-19 patients. Further, even if the COVID-19 infection is controlled and stable, whereas the D-dimer levels are rapidly increasing (or if significant increase appear without underlying disease progress) the recommendation is to rule out or confirm DVT by venous echo-Doppler ultrasound of bilateral lower extremities².

Highlighting the meaning of an elevated D-dimer in COVID-19 patients, the webinar focused on research studies and findings that states older age, higher Sequential Organ Failure Assessment (SOFA) score, and elevated D-dimer at admission due to increased coagulation activity, were shown to be risk factors for death of adult patients with COVID-19. The risk factors may help clinicians to identify patients with poor prognosis at an earlier stage.³

The session also accentuated the importance of high quality D-dimer testing, the parameters to define it and the efficiency and cost-effectiveness it brings with it. By using an assay with high specificity, you may rule out 30-50% of all individuals with suspected VTE ⁴. High negative predictive value (NPV) allows you to trust the D-dimer results you get by avoiding sending ill patients home⁴. On the other hand, high specificity minimizes imaging on healthy patients benefitting the healthy patient and improving logistics of the healthcare system⁴. Among the various biomarkers of thrombosis, D-dimer is the recommended biomarker as an aid in the diagnosis of VTE (DVT and PE)⁵.

Guillaume Galpy, has worked on acute care testing for more than 24 years and has been a global industry expert in the field of Immunoassay. He is the name behind the launch of the first Troponin I automated assay in 1995 and several other markers such as natriuretic peptides and D-dimer. After graduating in biology and marketing from the University of Nice and Lyon in France, he joined Radiometer and is currently working as a Global Market Development Manager for Immunoassay at Radiometer Medical, Copenhagen.

[1] Konstantinides S et al. Eur Heart J 2014; 35:3033-69
[2] Zhai Z, Li C, Chen Y, et al. Prevention and Treatment of Venous Thromboembolism Associated with Coronavirus Disease 2019 Infection: A Consensus Statement before Guidelines. Thromb Haemost. 2020 Apr 21.
[3] Zhou F, Yu T, Du R, et al. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. Lancet. 2020 Mar 28; 395(10229): 1054-1062.
[4] Strandberg K. The clinical use of a D-dimer assay, Acutecaretesting.org June 2017
[5] Mazzolai L et al.European Heart Journal (2018) 39, 4208–4218 doi:10.1093/eurheartj/ehx003

– MB Bureau