The performance of rapid D-dimer ELISA assay has been validated as a part of various diagnostic work-ups in tertiary care hospitals for the exclusion of acute thromboembolism in the medical emergency department. In order to measure the performance of this test outside of predetermined protocols and in a different medical setting, we retrospectively analysed a cohort of adult patients admitted to the emergency department of a regional hospital with a suspicion of acute venous thromboembolism.
All D-dimer assays performed during an 18-month period were retrieved. The patients' data were collected from hospital charts. Six-month follow-up was determined either by a written or telephone questionnaire or after contact with the patient's physician. The patients for whom this process was completed were included in the study and a retrospective diagnostic assessment was performed using a combination of clinical probability and objective testing. The diagnosis was then compared to the result of the initial D-dimer assay.
During the study period 494 patients were included with 110 venous thromboembolic episodes. The sensitivity and negative predictive value of the D-dimer assay were respectively 94.5% (95% CI 88.4 to 97.7%) and 96.8% (95% CI 93.2 to 98.7%).
The yield of the rapid D-dimer assay in this study is comparable to the results of management studies performed in tertiary centres. D-dimer ELISA assay can be used to exclude venous thromboembolism, particularly in cases with a low clinical probability, in the emergency department and for larger populations in various clinical settings, even in the absence of a formal diagnostic work-up. False negative results can occur, particularly in the presence of a high clinical probability of acute thromboembolism.