D dimer in COVID 19

By – Dr Rujuta Patil

BDS, MDS, PDCR

COVID19 caused by SARS-CoV-2 is known to be strongly associated with hypercoagulopathies. Such an increase in the risk of thrombus formation and bleeding in COVID 19 patients has increased their need for hospitalization. Examples of few coagulopathies are – Venous thromboembolism, pulmonary thromboembolism, arterial thrombosis and disseminated intravascular coagulation.

These coagulopathies lead to formation of huge blood clots/ thrombus which are broken down by plasmin via activation of fibrinolytic pathway. Plasmin breaks fibrin present in blood clot into fragments which are called as D dimmers. Therefore raise in D dimer levels denotes underlying coagulopathy.

Many studies have shown elevated D dimer levels in COVID 19 patients. Significantly higher levels were found in critically ill hospitalized patients. Basically, D dimer can be used to rule out a thrombus/ huge blood clots.

The D dimer level estimation plus imaging like CT scan, angiogram can be combined with clinical signs and symptoms to diagnose coagulopathies. If D dimer levels are within normal range, it denotes absence of thrombotic activity.

Hence, D dimer can be used as an inflammatory coagulation biomarker. Such a piece of information can help doctors combat the COVID 19 associated coagulopathies and thereby reduce morbidity and mortality of patients.