Evaluation of the Innovance D-DIMER analytical performance

Background: Widespread use of D-dimer in recent years has led to the development of a number of new fully automated quantitative D-dimer assays. Methods: We evaluated the analytical performance of the particle-enhanced immunoturbidimetric assay Innovance D-DIMER (Siemens Medical Solutions) on the Behring Coagulation System (BCS) analyzer. Results: Within-run coefficients of variation (CVs) for samples with low, borderline, slightly, and extremely increased D-dimer concentrations were 2.1%-5.5%, whereas between-run CVs for control samples with low and extremely increased D-dimer were 5.5%-8.4%. The assay exhibited good linearity in the working range between 0.17 mg/L and 5.45 mg/L fibrinogen equivalent units (FEU), with the lower limit of detection of 0.099 mg/L FEU. The upper reference value determined in 40 plasma samples from healthy volunteers was 0.495 mg/L FEU. The results obtained in 457 fresh plasma samples were compared with results obtained with VIDAS D-Dimer Exclusion. Passing and Bablok regression analysis demonstrated highly significant correlation (y=1.370x-0.108, r=0.952, p<0.001). Bland and Altman difference plots demonstrated slightly higher results obtained with Innovance D-DIMER that was more pronounced with increasing values. Very good agreement between both assays was observed (kappa=0.860; 95% confidence interval (CI), 0.811-0.908). Conclusions: This study demonstrates that Innovance D-DIMER fulfills all analytical requirements for daily routine use. Clin Chem Lab Med 2009;47:945-51.