981 Dose the D-dimer test has a role in the diagnosis of cerebral vein thrombosis? A systematic review
Authors: Kassem Ahmed , Kumar Thirumoothy , Mohammed Mohammed Seif 
Published: June 2022

BackgroundThe D-dimer test has a diagnostic role in pulmonary embolism (PE) ‘ and deep vein thrombosis(DVT). In a low-risk patient with negative D-dimer, PE or DVT can safely be ruled out.1 2We aim to know whether the D-dimer has a similar role in cerebral vein thrombosis (CVT) diagnosis.Methods/DesignWe attempt to identify studies that assess D-dimer’s diagnostic accuracy and reporting its sensitivity and specificity in CVT diagnosis. A literature review was performed in PubMed from 1996 to July 2021, Google scholar, and BestBETs electronic resources. The AMSTAR tool was used to assess the quality of included studies.Abstract 981 Figure 1PRISMA flow chartAbstract 981 Table 1Description of the studies included in the systemic reviewStudyStudy typePatient groupOutcomesWeakness/commentsDentali et al, Italy, 20123A Systematic review and meta-analysis1134 Patient with suspected or diagnosed CVT. D-dimer with CT or MRI venography was done for all patients.D-dimer elevated in 145/155 CVT patients, sensitivity 93.8%, and normal in 692/771 of non CVT patients, specificity 89.7%The included studies are of low quality with variable designs. Diffèrent reference tastes, variable d dimer assays and cut-off points.Alons et al, Netherlands 20154A Systematic review and Meta-analysis636 patient with isolated headache & normal neurological exam. D-dimer & CT or MRI venography was done for all patient45/636 CVT cases, One had a normal D-dimer. Sensitivity: 97.8%. Specificity: 84.9% Patients with normal neurological exam & CT brain with a negative D-dimer are less likely to have CVT, < 0.2%.The study looked for low risk patient, with isolated headache and normal neurological exam . high risk group with neurological symptomswas excluded, so the results can’t be generalized.Six potential studies were excluded because of missing data about an isolated headache.Thammishetti V. India, 20165Prospective cohort study,80 patients with CVTS confirmed or excluded by CT or MRI venography .D-dimer was done in all patients65/80 conformed CVT cases.The D-dimer sensitivity and specificity was 80.62% & 80% respectively.No statistical significant value for D-dimer between CVT and non CVT group during puerperal period.No details about patients recruitments, with the possibility of selection bias.The used D-dimer semiquantative latex test has less sensitivity than then-recent D-dimer assays.Results/ConclusionsOut of 66 non-duplicated citations, 15 articles were relevant to our clinical question. Eight articles were included in one of the retrieved meta-analyses, and four articles were excluded during data collection because of unclear results. Two systematic reviews & meta-analyses3 4and one cohort study5were included for the systematic review. The selection process is shown in figure (1). The studies are tabled with details of author, publication date, population details, and results as in table (1). Most studies show D–dimer has a high sensitivity, around 93 to 97%, in CVT diagnosis. However, its sensitivity is affected by age, thrombus sizes, and the method used in the D-dimer assay.A review shows that more CVT extension & earlier presentation (<2weeks) were correlated with higher D-dime levels. Unfortunately, most of the studies are not high-quality studies, with variable designs, population, and reference standard tests. The studies showed that D dimer could help predict CVT in combination with risk factors and clinical presentation.We concluded that the normal D-dimer only should not be used to exclude CVT. There is a probability of using D-dimer in CVT risk scoring and pre-imaging negotiation, and for that purpose, larger and higher-quality studies are needed.ReferencesStam J. Thrombosis of the cerebral veins and sinuses.N Engl J Med2005 Apr 28;352(17):1791–8. doi:10.1056/NEJMra042354. PMID: 15858188.Agnelli G, Becattini C. Acute pulmonary embolism.N Engl J Med2010 Jul 15;363(3):266–74. doi:10.1056/NEJMra0907731. Epub 2010 Jun 30. PMID: 20592294.Dentali F, Squizzato A, Marchesi C, Bonzini M, Ferro JM, Ageno W. D-dimer testing in the diagnosis of cerebral vein thrombosis: a systematic review and a meta-analysis of the literature.J Thromb Haemost2012 Apr;10(4):582–9. doi:10.1111/j.1538-7836.2012.04637.x. PMID: 22257124.Alons IM, Jellema K, Wermer MJ, Algra A. D-dimer for the exclusion of cerebral venous thrombosis: a meta-analysis of low risk patients with isolated headache.BMC Neurol2015 Jul 28;15:118. doi:10.1186/s12883-015-0389-y. PMID: 26215857; PMCID: PMC4517419.Thammishetti V, Dharanipragada S, Basu D, Ananthakrishnan R, Surendiran D. A prospective study of the clinical profile, outcome and evaluation of d-dimer in cerebral venous thrombosis.J Clin Diagn Res2016 Jun;10(6):OC07–10. doi:10.7860/JCDR/2016/19114.7926. Epub 2016 Jun 1. PMID: 27504325; PMCID: PMC4963685.