Hemolysis Interference in the Ortho-Clinical Diagnostics Vitros ECi cTnI Assay

摘要

Assay specificity is an important requirement for cardiac troponin measurement (1). This study examines the effect of hemolysis on two troponin I (cTnI) assays: the Ortho-Clinical Diagnostics Vitros? ECi and the Beckman-Coulter Access 2 (AccuTnI).Erythrocyte hemolysates were prepared according to the procedure of Meites (2). Aliquots were added to unhemolyzed, heparinized plasma pools with three different cTnI concentrations (for the ECi, 0.05, 0.1, and 0.3 μg/L; for the AccuTnI, 0.1, 0.2, and 0.5 μg/L) to produce severely hemolyzed specimens. Each of these specimens was diluted in the respective unhemolyzed plasma pool to form nine samples. The hemolysis index (HI; Roche 917 analyzer) and cTnI (ECi and Access) were measured in all samples. The magnitude of hemolysis interference varied with the cTnI concentration. Multiple linear regression using the HI and measured cTnI in the hemolyzed sample as variables to predict true cTnI concentration (the original pool cTnI concentration) was performed with Sigmastat 2.0 (Jandel Corporation). A … E-mail Robert_Hawkins{at}ttsh.com.sg