Evaluation of the usefulness of a D dimer test in combination with clinical pretest probability score in the prediction and exclusion of Venous Thromboembolism by medical residents

Abstract

IntroductionVenous thromboembolism (VTE) requires urgent diagnosis and treatment to avoid related complications. Clinical presentations of VTE are nonspecific and require definitive confirmation by imaging techniques. A clinical pretest probability (PTP) score system helps predict VTE and reduces the need for costly imaging studies. d-dimer (DD) assay has been used to screen patients for VTE and has shown to be specific for VTE. The combined use of PTP and DD assay may improve exclusion of VTE and safely avoid imaging studies.Materials and methodsWe prospectively used the Wells PTP score and a DD test to evaluate 230 consecutive patients who presented with VTE symptoms. The receiver operating characteristic curve was used to identify a new DD cutoff value, which was applied to VTE diagnosis and compared with the upper limit of locally established reference range for prediction of thrombosis alone and in combination with the clinical PTP score.ResultsWe evaluated 118 patients with VTE symptoms fulfilling the inclusion criteria, 64 (54.2%) with clinically suspected deep vein thrombosis (DVT) and 54 (45.8%) with symptoms of pulmonary embolism (PE). The PTP was low in 28 (43.8%) and moderate/high in 36 (56.25%) of the suspected DVT patients, and low in 29 (53.7%) and moderate/high in 25 (46.3%) of the suspected PE patients. Eighteen cases were confirmed by imaging studies: 9 DVT and 9 PE. The agreement between confirmed cases and PTP was significant with PE but not DVT. The negative predictive value for both DVT and PE with current DD cutoff value of <250 μg/L DDU was 100%, whereas with the calculated cutoff the NPV was 88%.ConclusionsWe confirm that PTP score is valuable tool for medical residents to improve the detection accuracy of VTE, especially for PE. The DD cutoff value of 250 μg/L FEU is ideal for excluding most cases of low PTP; however, the calculated cutoff was less specific for the exclusion of VTE.

D-Dimer levels are correlated with disease activity in Crohn's patients

“…D-dimer is a fibrin-derived fragment that is released into the blood when cross-linked fibrin is broken down by the fibrinolytic system [ 18 ]. And the D-dimer assay has gained significance as a tool that assists in clinical decisions on the presence of thrombosis [ 19 ].…”

Canine mammary anaplastic carcinoma with concurrent aorto-iliac thrombosis in a dog: a case report

“…In human and veterinary medicine, D-dimers are laboratory markers that are used clinically to detect early thromboembolism (TE) (Nelson and Andreasen 2003;Owaidah et al 2014). Other laboratory markers of coagulation activation, such as fibrinopeptides A and B, fibrinogen degradation products, prothrombin fragments 1 and 2, and thrombin-antithrombin complexes, have been proposed and used for TE diagnosis, however, only the D-dimer assay has been shown to have clinical utility in people (Bounameaux 1996).…”

“…Mammary gland tumours (MGT) are among the most commonly diagnosed tumours in female dogs (Philibert et al 2003). Epithelial tumours, which are the most commonly diagnosed histologic type of neoplasia affecting the mammary gland, constitute more than 90% of all tumours of the mammary gland (Gilbertson et al 1983).…”

Compliance to clinical pathways in the management of suspected pulmonary embolus: are there cost implications?

“…The Wells score and d ‐dimer are proven to reduce the number of CTPA performed on low‐risk PE patients and has a very good negative predictive value . Overall in both hospitals the standard protocol was not followed for 40% of patients.…”