Consultant - Hematopathology SAHYADRI SPECIALITY LABS Pune, Maharashtra, India
Background: D-dimer is one of those very few test parameters that is considered as both, boon and bane. On one hand, D-dimer has immense value in diagnostic and prognostic management of VTE and sepsis; On the other hand, commonly, it is marred by complexities, such as pre-test probability and several analytical and post-analytical issues thereby posing a challenge to effective clinical decision making. All this was exacerbated during the COVID-19 pandemic. A parameter traditionally used for ruling out VTE, or in sepsis scoring, suddenly was in the driving seat of hemostatic management of a disease that was new to mankind. The cut-off values of VTE exclusion were extrapolated for assessing the severity of COVID-19 associated coagulopathy and, despite the guidance and recommendations, used independently in guiding anti-coagulation. Furthermore, often, d-dimer was run on different platforms. Now, after COVID, when it is time to establish the role of D-dimer in predicting the recurrence of VTE and in prognostication and risk stratification of various cancers and acute chest pains, the foremost challenge is the skewed perception and apprehension of the prescribers in using this incredible tool.
Aims: This study was intended to evaluate the correlation between values of D-dimer across different platforms.
Methods: D-dimer values were assessed for 97 COVID and 5 non-COVID patients on 2 different analysers. The results were also evaluated vis-à-vis other biomarkers of COVID-19.
Results: Large (55.9%) number of tests values between the two analysers were dissimilar. Also, there was no definite pattern of correlation with IL-6, CRP or fibrinogen in COVID-19 patients.
Conclusion(s): Test values of D-dimer are assay specific and, hence, expected to differ between methods and analysers. Optimal laboratory practices and conviction based adoption by prescribing clinicians will help realise the immense clinical utility of this test parameter in oncology and cardiac settings beyond COVID and VTE.
