Mindray CL-900i Assay: An Effective assay for HBsAg Screening with Superior Specificity

Abstract The CLIA automated Abbott-Architect HBsAg screening assay is globally recognized for its superior sensitivity but notably low specificity. This mandates positive results confirmation by another confirmatory assay, such as the widely used Abbott-Architect HBsAg neutralizing assay. Aim: To evaluate performance of the new CLIA Mindray-CL-900i HBsAg screening assay compared to Architect neutralizing/confirmatory assays. Methods: 200 archived HBsAg positive and negative samples by Architect screening were selected for this study. These samples were classified as follows: T.P. (n=39): positive by both Architect screening and confirmatory assays; T.N. (n=144): negative by both Architect screening and confirmatory assays; F.P. (n=17): positive by Architect screening but negative by confirmatory assay. All samples were retested using Mindray-CL-900i HBsAg screening assay. Results: Compared to Architect confirmatory assays, Mindray HBsAg CL-900i demonstrated perfect agreement with the confirmatory assay, as indicated by a Cohen's Kappa value of 0.98 (0.95 - 0.10). Mindray-CL-900i exhibited a sensitivity of 97%, PPV of 100%, and NPV of 99%. The specificity was 100%, as none of the T.N. and F.P. results were identified as positive. Conclusion: Mindray-CL-900i could offer a cost-effective alternative for HBsAg screening, boasting perfect specificity and overcoming the limitations of current automated assays.