oa Can a negative D-Dimer Test help in ruling out the diagnosis of Cerebral Venous Thrombosis?

Background: The 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. This work aims at investigating whether the D-dimer has a similar role in cerebral vein thrombosis (CVT) diagnosis. Methods: A literature review was performed in PubMed, Google scholar, and BestBETs electronic resources to identify studies published from 1996 to July 2021 that assess D-dimer's diagnostic accuracy and report its sensitivity and specificity in CVT diagnosis. The AMSTAR tool was used to assess the quality of the included studies. Results: Out 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 and meta-analyses^1,2 and one cohort study³ were included for the systematic review. The selection process is shown in Figure 1. The studies are reported with details of author, publication date, population details, and results are shown in Table 1. Most of the studies show that D–dimer has a high sensitivity which is estimated to be around 93% to 97% in CVT diagnosis. However, its sensitivity is affected by age, thrombus sizes, and the method used in D-dimer assay.

A review shows that more CVT extension and earlier presentation, prior to 2 weeks, were correlated with higher D-dimer 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. Conclusion: 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.