Evaluation and performance characteristics of the automated coagulation analyzer ACL TOP

The ACL TOP is a fully-automated random-access multiparameter coagulation analyzer equipped with a photo-optical clot-detection unit. It is designed to perform coagulation, chromogenic and immunologic assays with continuous loading capabilities for samples, reagents and disposables.

The instrument was evaluated in a coagulation laboratory of a university hospital with respect to its technical features in the determination of routine coagulation (prothrombin time, activated partial thromboplastin time, fibrinogen and single coagulation factor levels), chromogenic (anti-activated factor X, antithrombin and protein C activities) and immunologic assays (free protein S and von Willebrand factor antigen concentrations).

Using fresh and lyophilized plasma samples, the intra-assay and inter-assay coefficients of variation were below 5% for most of the parameters both in the normal and in the pathological ranges. For clotting assays performed at 671 nm, no significant interference could be demonstrated with hemolytic, icteric and lipemic samples as demonstrated by results similar to those obtained using a mechanical clot-detection-based analyzer (STAR). No sample carryover was detected in measuring alternatively heparinized (1.0 IU/mL unfractionated heparin) and normal plasma samples. The results of the different coagulation, chromogenic and immunologic assays obtained on the ACL TOP were well correlated with those obtained on the STAR analyzer with the correlation coefficient (r) in the range from 0.876 to 0.990.

Our results demonstrated that using the ACL TOP analyzer, routine hemostasis testing can be performed with satisfactory precision and the same applied to more specialized and specific tests such as single factor activity or antigen concentration.