Magnitude of D-dimer matters for diagnosing pulmonary embolus.
Publication Type | Academic Article |
Authors | Shah K, Quaas J, Rolston D, Bansal S, Bania T, Newman D, Wiener D, Lee J |
Journal | Am J Emerg Med |
Volume | 31 |
Issue | 6 |
Pagination | 942-5 |
Date Published | 05/16/2013 |
ISSN | 1532-8171 |
Keywords | Fibrin Fibrinogen Degradation Products, Pulmonary Embolism |
Abstract | OBJECTIVE: The objective of this study is to determine whether the magnitude of the D-dimer correlates with a higher likelihood of pulmonary embolus (PE). METHODS: We performed an electronic chart review at our academic, tertiary care center, annual emergency department (ED) census greater than 100000. All patients with a chest computed tomographic (CT) scan with intravenous contrast and an elevated D-dimer level obtained in the ED between January 2001 and July 2008 were identified. Specific, predetermined, predefined data elements including sex, age, D-dimer level, and final ED diagnosis were recorded by a hypothesis-blinded extractor using a preformatted data form. D-dimer level less than 0.58 μg/mL constitutes the normal laboratory reference range for our turbidometric D-dimer assay. Data were analyzed using standard statistical methods, and a linear regression analysis was performed for correlation analysis of D-dimer and diagnosis of PE. RESULTS: We identified 544 subjects who had both a chest CT scan performed and an elevated D-dimer level obtained in the ED. Fifty-eight subjects (10.7%; mean D-dimer, 4.9 μg/mL) were diagnosed with PE, and 486 (89.3%; mean D-dimer, 2.0) did not have a PE. The percentages of PE diagnoses for D-dimers in the ranges 0.58 to 1.0, 1.0 to 2.0, 2.0 to 5.0, 5.0 to 20.0, and greater than 20.0 (n = 11) were 3.6%, 8.0%, 16.2%, 35.3%, and 45.5%, respectively. The positive predictive value of PE for D-dimer level cutoffs of greater than 0.58, greater than 1.0, greater than 2.0, greater than 5.0, and greater than 20.0 was 10.7%, 14.6%, 22.2%, 37.8%, and 45.5%, respectively. Increasing D-dimer values were strongly correlated with the presence of PE (odds ratio, 1.1685 per stratum; P < .001). CONCLUSION: Increasing magnitude of D-dimer correlates with increasing likelihood of PE diagnosed by CT angiography. |
DOI | 10.1016/j.ajem.2013.03.009 |
PubMed ID | 23685058 |