Performance evaluation of the FDA-approved Determine™ HIV-1/2 Ag/Ab Combo assay using plasma and whole blood specimens

J Clin Virol. 2017 Jun;91:95-100. doi: 10.1016/j.jcv.2017.03.019. Epub 2017 Mar 24.


Background: The Determine™ HIV-1/2 Ag/Ab Combo (DC) rapid test can identify HIV-1 infection earlier than rapid antibody-only tests in plasma specimens.

Objectives: We compared the performance of DC with a laboratory-based antigen/antibody (Ag/Ab) combo assay in plasma and evaluated antigen reactivity in whole blood specimens.

Study design: We tested by DC 508 plasma specimens collected in a prospective study and 107 sequential plasma and simulated whole blood specimens from 20 seroconversion panels. Previous results using the ARCHITECT (ARC) Ag/Ab combo assay were compared to DC results. In seroconversion panels, the days from the first HIV1 RNA-positive test to first DC-reactive in plasma and whole blood was compared. McNemar's and Wilcoxon signed rank tests were used for statistical analysis.

Results: Of 415 HIV-positive samples, ARC detected 396 (95.4%) and DC 337 (81.2%) (p<0.0001). DC was reactive in 50.0% of ARC-reactive/MS-negative, 78.6% of ARC-reactive/MS-indeterminate, and 99.6% of ARC-reactive/MS-HIV-1-positive or -undifferentiated specimens. DC antigen reactivity was higher among ARC-reactive/MS-negative than MS-indeterminate samples. In 20 HIV-1 seroconversion panels, there was a significant difference between DC reactivity in plasma (91.1%) and whole blood (56.4%) (p<0.0001). DC with whole blood showed a significant delay in reactivity compared to plasma (p=0.008).

Conclusions: In plasma, DC was significantly less sensitive than an instrumented laboratory-based Ag/Ab combo assay. DC in plasma was significantly more sensitive compared to whole blood in early HIV-1 infections. With the U.S. laboratory-based diagnostic algorithm, DC as the first step would likely miss a high proportion of HIV-1 infections in early stages of seroconversion.

Keywords: Antigen-antibody detection; HIV diagnostics; Rapid test.

Publication types

  • Evaluation Study

MeSH terms

  • AIDS Serodiagnosis*
  • HIV Antibodies / blood*
  • HIV Antibodies / immunology
  • HIV Antigens / blood*
  • HIV Antigens / immunology
  • HIV Infections / diagnosis*
  • HIV Infections / epidemiology
  • HIV Infections / virology
  • HIV Seropositivity
  • HIV-1 / immunology
  • HIV-1 / isolation & purification
  • HIV-2 / immunology
  • HIV-2 / isolation & purification
  • Humans
  • Immunoassay*
  • Mass Screening
  • Plasma / virology
  • Prospective Studies
  • Reagent Kits, Diagnostic
  • United States
  • United States Food and Drug Administration


  • HIV Antibodies
  • HIV Antigens
  • Reagent Kits, Diagnostic