Validation and Comparison Study for Fourth Generation HIV Test Kit

Abstract

Abstract Introduction/Objective CDC recommends the use of 4th generation HIV test as the first line of screening. Alere Determine HIV – 1/2 Ag/Ab Combo (Abbott Diagnostics Scarborough, Inc., Scarborough, Maine) (Alere) is a qualitative 4thgeneration assay that detects HIV 1/2 antibodies and p24 antigen. In this validation study, Alere was compared with OraQuick Advance Rapid HIV 1/2 Antibody test (OraSure Technologies, Inc., Bethlehem, PA) (Oraquick), a qualitative 3rd generation test and BioPlex (Bio-Rad Laboratories, Hercules, California) a 5th generation test that detects and differentiates between HIV 1 and 2 antibodies and p24 antigen. Methods/Case Report Comparison study: Forty-five samples were tested simultaneously on the three assays. Results for the patient samples were confirmed with Geenius (Bio- Rad Marnes-La-Coquette, France) or PCR assays for antibody or antigen positive cases respectively. Precision study A HIV-1 antibody positive and an all-negative sample were tested 10 times each to validate the precision of the Alere test. Dilution study A positive sample for HIV-1 antibody was used for dilution with a HIV negative serum sample. Diluted samples from 1:10 to 1:1000 were tested using Alere and BioPlex. Results (if a Case Study enter NA) Comparison study revealed that sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for Alere test were 100%. Sensitivity for Oraquick was 86.6% and NPV was 77.77%. Specificity and PPV were 100%. BioPlex showed sensitivity and NPV of 100%, but specificity was 78.5% and PPV was 90.90%. Precision study showed reproducible results on the Alere test. Dilution study revealed that Alere assay gave positive results up to 1:300 dilution, and BioPlex assay was positive up to 1:500 dilution. Conclusion Our studies showed that Alere had the sensitivity and specificity of 100% making it an effective screening test in acute settings. BioPlex assay demonstrated that it was the most sensitive test with quantitative index for the HIV 1 and 2 antibodies and p24 antigen. Therefore, both Alere and BioPlex tests are good initial screening tests