Performance of the automated and rapid STA Liatest D-dimer on the STA-R analyzer.
OBJECTIVE
The aim of the present study was to investigate the accuracy indices of the new automated and rapid microlatex D-dimer assay, STA Liatest D-Di, on the STA-R analyzer and to compare it with established D-dimer assays.


METHODS
D-dimer testing has been performed in 103 consecutive outpatients with suspected deep venous thrombosis (DVT). Diagnosis of DVT was established by contrast venography or color-coded duplex ultrasonography. D-dimers plasma concentrations were measured with the STA Liatest D-Di on the STA-R coagulation analyzer, with a reference ELISA technique (Asserachrom), with an automated quantitative latex-based immunoassay (Tinaquant) and with the VIDAS D-dimer test.


RESULTS
In total, 103 eligible outpatients entered the current study and DVT was detected in 46 patients (44.6%). Two duplicate D-dimer measurement with the STA Liatest D-Di revealed excellent correlation (r(S)=0.996) and almost identical sensitivity (each 98%), specificity (49% and 50%), negative predictive value (NPV; each 97%), positive predictive value (PPV; 61% and 62%) and exclusion rate (27% and 28%), respectively. Comparison of the STA Liatest D-Di with the other D-dimer tests revealed highly significant correlations (r(S)=0.951-0.979), highly comparable regression and excellent agreement in clinical interpretation of the test results (kappa coefficients 0.812-0.856). Moreover, sensitivity, specificity, NPV, PPV and exclusion rate at a cut-off level of 500 ng/ml were in the same range for the STA Liatest D-Di when compared with the other D-dimer tests.


CONCLUSIONS
The Liatest D-Di performed on the coagulation analyzer STA-R compares favorable with the VIDAS, Tinaquant and Asserachrom D-dimer tests and is suitable for the safe exclusion of DVT in symptomatic outpatients. The test can be included in an algorithm for DVT diagnosis including other diagnostic tools.
Waser
Gregor
G
Division of Hematology and Central Hematology Laboratory, Kantonsspital Luzern, 6000 Luzern 16, Switzerland.
Kathriner
Silvio
S
Wuillemin
Walter A
WA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001331:Automation; D001780:Blood Coagulation Tests / Q000295:instrumentation* / Q000592:standards; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D020246:Venous Thrombosis / Q000175:diagnosis*
D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D