Laboratory evaluation of the UniCel DxI 800 analyser (Beckman Coulter) for detecting HBV and HCV serological markers

Abstract

Background Due to their high prevalence, hepatitis B virus (HBV) and hepatitis C virus (HCV) infections need accurate and rapid diagnosis tools. Objectives Technical performances of the UniCel DxI 800 analyser (Beckman Coulter) and a comparison with the Vitros ECi (Ortho Clinical Diagnostics) were performed for five serological markers: HBsAg, total anti-HBc, anti-HBc IgM, anti-HBs and anti-HCV. Study design Reproducibility was determined by repeated tests on the manufacturers’ controls. The performance of the UniCel DxI 800 was assessed by testing negative and positive samples previously analysed with the Vitros ECi. The accuracy and linearity of anti-HBs assay were evaluated using the WHO international standard (W1042). Results The intra-assay and inter-assay coefficients of variation were: 0.8% and 4.4% for HBsAg, 2.4% and 6.2% for anti-HBc, 5% and 8.7% for anti-HBc IgM, 2.1% and 5.1% for anti-HBs and 3.7% and 7.4% for anti-HCV. The two methods were concordant: 100% agreement for the five markers except for the negative HBsAg sera (99%). The anti-HBs results correlated well with the Vitros ECi ( r = 0.925 with p < 0.0001) and the WHO standard ( r 2 = 0.9996). Throughput was 216 tests/h. Conclusion The high throughput, specificity and sensitivity make UniCel DxI 800 assays useful for routine diagnoses of HCV and HBV infections.