Diagnostic performance of a fully automated chemiluminescent enzyme immunoassay for Alzheimer's disease diagnosis

The variability of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers (A beta 42, t-Tau and p-Tau) undermines their full-fledged introduction into routine diagnostics and clinical trials. The introduction of automatic systems can improve the diagnostic performance promoting standardization and reducing the impact of preanalytical and analytical factors. Here we assessed the diagnostic performance of a fully automated chemiluminescent enzyme assay (LUMI-PULSE) and compared it with that obtained by using the classical manual enzyme-linked immunosorbent assays (ELISAs). Patients were clinically diagnosed as AD (n = 42) and non-AD (n = 38). Clinical diagnosis was confirmed at follow-up. LUMIPULSE A beta 42 was reduced in AD (969.4 +/- 329.6 pg/mL vs. 1625.9 +/- 745.9 pg/mL, p < 0.001), whereas LUMIPULSE t-Tau was increased in AD (768.2 +/- 281.0 pg/mL vs. 337.5 +/- 159.1 pg/mL, p < 0.001) compared to non-AD patients. Both LUMIPULSE A beta 42 (AUC = 0.78, spec. = 0.74, sens. = 0.76) and t-Tau (AUC = 0.94, spec. = 0.93, sens. = 0.87) showed good accuracy in distinguish AD from non-AD and a high correlation with the manual ELISAs (r -= 0.87, p < 0.001 and r = 0.92, p < 0.001, respectively). LUMI-PULSE improves clinical accuracy in AD diagnosis, promoting the use of standardized values for CSF biomarkers with a good correlation with classical manual assays.