The objective of this pilot study was to determine the clinical utility of the SimpliRed D-dimer bedside assay to identify patients with bacteremia in a university hospital Emergency Department. We tested 265 patients and compared blood culture results with a novel D-dimer semiquantitative whole blood assay. Bacteremia was confirmed in 25/262 patients. Sensitivity of D-dimer assay was 66.7% for Gram-positive bacteremia and 61.5% for Gram-negative bacteremia with negative predictive value of 98% for Gram-positive and 96% for Gram-negative bacteremia patients. Measurement of D-dimer appears to be of value in identifying patients at low risk for bacteremia and can be accomplished rapidly using a whole blood semiquantitative bedside assay. Although increases in D-dimer are not detected in all patients subsequently documented to have bacteremia on a single sampling, the results of this and other earlier studies suggest assay of D-dimer is useful in rapid differentiation of patients with bacteremia from those who have no bacteremia using blood culture positivity as the standard for bacteremia.