Abstract: |
We evaluated a new fully automated procedure for quantitative measurement of prostate-specific antigen (PSA) by the Microparticle Enzyme Immunoassay (MEIA) technology developed for the Abbott IMx® automated immunoassay system. The performance characteristics of the Abbott IMx PSA assay (y) were evaluated and compared with those of the Hybritech Tandem®-E PSA assay (x), a solid-phase two-site immunoenzymometric assay. PSA values for both assays were well correlated (r = 0.99); regression analysis yielded the equation y = 0.92x - 0.23 μg/L. The Abbott assay proved reliable and reproducible, as shown by the intra- and interassay coefficients of variation (2.0-3.4% and 3.1-4.7%, respectively). The assay gave a linear standard curve up to 100 μg/L and was very sensitive (detected PSA <0.1 μg/L). This analytical sensitivity was comparable with that of the Tandem-E PSA assay. Overall, the IMx PSA assay demonstrated the accuracy, precision, linearity, and intermethod correlation required for monitoring patients with prostate cancer. |