Performance of the automated and rapid HemosIL D-Dimer HS on the ACL TOP analyzer

We evaluated the analytical performance of the new commercial HemosIL D-Dimer HS, a latex-enhanced turbidimetric immunoassay, from Instrumentation Laboratory for D-dimer measurement on the ACL TOP automated analyzer. The recommended cut-off for this immunoassay is 243 ng/ml. The within-run and between-run coefficients of variations of D-Dimer HS for low, intermediate and high D-dimer concentrations were: 3.3-6.6%, 2.3-2.6%, 2.4-3.2%, respectively. The assay was proven linear in a range of D-dimer concentrations comprised between 319 and 2274 ng/ml. Results of 171 citrated plasma samples were compared with those of the reference commercial immunoassay VIDAS D-Dimer. Although the nonparametric regression according to the method of Passing and Bablok and the relative Spearman's correlation coefficient were excellent (HemosIL D-Dimer HS = 1.30 x VIDAS - 384; r = 0.964, P < 0.001), some discrepancies could be observed in Bland-Altman plots analysis. On the basis of the present evaluation, we conclude that the analytical performance and the main technical features of new HemosIL D-Dimer HS assay make it a suitable method for the rapid quantification of D-dimer in clinical laboratories. Further studies are however needed to confirm the safety of the assay and to determine the most optimal cutoff level in patients with venous thromboembolism.