Could a D-dimer/fibrinogen ratio have a role in ruling-out venous thromboembolism?

Abstract

BackgroundDiagnosis of venous thromboembolism (VTE) requires chest CT angiography for pulmonary embolism and venous ultrasound for deep vein thrombosis. To reduce imaging, guidelines recommend D-dimer levels to rule-out VTE in patients with a low pre-test probability. The most widely used D-dimer cut-off is 500 ng/mL. This cut-off has low specificity, meaning many patients without disease require imaging.MethodsIn this retrospective chart review, we evaluated the diagnostic performance of the D-dimer/fibrinogen ratio (DFR) for identifying thromboembolism and compared it to the performance of two different D-dimer cut-offs (500 ng/mL and 1000 ng/mL) in patients who underwent a chest CT angiography or a venous ultrasound in the ED of San Raffaele Hospital, Italy, in 2017. Patients had a retrospective Wells score calculated after chart review, identifying both high-risk and low-risk pre-test probability patients for this study and low probability patients were further stratified into low-risk of deep vein thrombosis or pulmonary embolism.ResultsEnrolled patients included 92 with suspected pulmonary embolism and 154 with suspected deep vein thrombosis; of whom 67 (27%) were diagnosed with VTE. The most accurate cut-off for DFR in terms of discriminative power was 2.65. In the whole sample and in low-risk patients, this cut-off had the same sensitivity values of the 500 ng/mL D-dimer cut-off (97% (95% CI: 89.8% to 99.2%)), while slightly lower sensitivity values were found for the 1000 ng/mL D-dimer cut-off (95.5% (95% CI: 87.6% to 98.5%)). Specificity was higher for the 2.65 DFR cut-off (55.3% (95% CI: 48.0% to 62.4%)) in the whole sample compared with both 500 ng/mL D-dimer cut-off (22.9% (95% CI: 17.4% to 29.6%)) and 1000 ng/mL D-dimer cut-off (45.8% (95% CI: 38.7% to 53.1%)). Similar results were found in all subgroups.ConclusionA DFR, with a cut-off of 2.65, may improve the specificity for VTE patients when compared with D-dimer alone in high-risk VTE emergency medicine populations. This is exploratory information only, needing evaluation in prospective, multicentre studies, prior to consideration for use in routine clinical work.

Acute blood biomarker profiles predict cognitive deficits 6 and 12 months after COVID-19 hospitalization

“…In addition, raised D-dimer correlates with reduced pulmonary perfusion in patients hospitalized with COVID-19 (ref. 46 ) and venous thromboembolism is thought to be associated with raised D-dimer but normal fibrinogen 47 , which would explain why this mechanism is captured by a separate dimension of covariation. It is plausible that COVID-19-induced pulmonary embolisms (PEs) lead to cerebral hypoxia which in turn leads to a subtle degree of cognitive impairment, which is subjectively evident but not easily objectively measured (as subjective cognitive deficit can be a sensitive sign of early decline) 48 .…”

Diagnostic value of D-dimer to fibrinogen ratio for pulmonary embolism in postpartum women

“…D-dimer to fibrinogen ratio (DFR) is a valuable predictor of PE, and combining D-dimer with fibrinogen can enhance the specificity of D-dimer and improve accuracy [ 7 , 14 ]. Studies have demonstrated the value of DFR in predicting PE in patients in the emergency department [ 15 , 16 ]. Anyway, the diagnostic value of DFR in postpartum women suspected of having PE still unclear.…”

Discussion on operation: To compare the curative effect of PMT and CDT in the treatment of middle and high risk stratified APE and the clinical application value of serum BNP, TnI and plasma DFR levelse

“…Therefore, plasma TnI is usually used as a common diagnostic index in clinical APE, which can evaluate the severity of cardiopulmonary function damage. D-dimer/fibrinogen ratio ( 7 ) can be used as an active index of thrombosis. At present, it is widely used in diseases such as venous thrombosis and ischemic stroke, and its sensitivity is higher than that of simple D-dimer.…”