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Updated: May 14, 2026
Rapid Screening of HIV Reverse Transcriptase and Integrase Inhibitors
Published on: April 9, 2014
Evaluation of a rapid antigen and antibody combination test in acute HIV infection
Silvia Faraoni1, Andrea Rocchetti, Franca Gotta
1Laboratory of Microbiology and Virology, Infectious Diseases Department, Amedeo di Savoia Hospital, Turin, Italy.
Background:
New strategies at implementing HIV testing including rapid HIV assays are highly recommended to avoid late diagnosis. To shorten the diagnostic window period, the first point-of-care HIV assay, Determine HIV ½ Ag/Ab Combo (D4G, Alere, I) for the combined detection of p24 and anti-HIV antibody has been recently marketed and mainly tested in high prevalence setting.
Objectives:
To establish D4G performances in acute HIV infection (AHI) in a setting at low HIV-1 prevalence.
Study Design:
D4G performances were compared with HIV-1 RNA levels in a panel of well-characterized serum specimens from 17 patients with AHI. For specificity, 124 anti-HIV negative serum specimens from patients seeking HIV testing were studied.
Results:
D4G detected HIV infection in 15/17 patients. D4G antigen was positive in only 5 patients (29.4%), 4 of them with a viral load >10 million copies/mL. D4G antibody was reactive in other 10 patients (sensitivity: 58.8%, viral load from 70,161 to 8,120,000 copies/mL). Combined D4G sensitivity for acute HIV-1 infection was 88.2%; no false positive or invalid result was recorded (100% specificity, positive and negative predictive values: 100% and 98.4%, respectively).
Conclusion:
In spite of a poor antigen sensitivity with optimal performances only for viral load >10 million copies/mL, D4G performances in acute HIV-1 infection were enhanced by the addition of p24 testing to the antibody. Improved HIV rapid testing to shorten the window period is important as rapid tests play a major role in expanding access to HIV testing and preventing HIV transmission.
