Advances in HIV Ag/Ab diagnosis: ALINITY vs ARCHITECT
Objective: To compare and validate the performance of the new Abbott ALINITY i HIV Ag/Ab Combo assay against the current ARCHITECT HIV Ag/Ab Combo.
Method: 123 patient’s samples, previously tested on the ARCHITECT i2000 analyser, were tested on the ALINITY i system. Both instruments use chemiluminescence immunoassay technology for the qualitative detection of HIV p24 antigen and antibodies HIV type 1 and 2. All reactive and discrepant results were confirmed using a third platform (Vidas immunoassay analyzer).
Findings: 119 of the 123 HIV samples (96.7%) matched the ARCHITECT and the ALINITY. The remaining 4 discrepant samples (3.3%) were analysed by the Vidas, all of which yielded negative results, verifying the ALINITY results. Furthermore, testing of HIV on the ALINITY met the laboratory and manufacturer acceptance criteria (stated specificity of 99.89% (95%CI: 99.67% to 99.98%)). A good correlation found between the two instruments (R2=0.9926). Analysis of External Quality Assessment NEQAS HIV samples on the ALINITY did not deviate from the expected results.
Conclusion: The ALINITY HIV Ag/Ab Combo assay performed well and met the manufacturer and laboratory acceptance criteria. The ALINITY assay demonstrated a better sensitivity and specificity. In addition, the ALINITY’s ease of use is anticipated to have positive implications in meeting turnaround, subsequently enhancing the quality and efficiency of the service. This shows advances in diagnostic methods for the detection of HIV and other viruses could potentially improve diagnosis and treatment for patients due to more accurate results.