[Early diagnosis of primary HIV infections: using a combined screening test (p24 antigen and anti-HIV antibodies)].
Laboratory diagnosis of HIV infection is based on the detection of HIV antibodies. There is a delay between infection and seroconversion (i.e. the appearance of specific HIV antibodies) corresponding to a window period which may last several weeks. Reduction of the length of the window period might be achieved by using p24 antigen and/or viral nucleic acid detection assays. We have evaluated a new screening assay (VIDAS HIV DUO) designed for the concurrent detection of HIV antibodies and p24 antigen, using sequential samples of 34 HIV-1 seroconverting patients and 236 HIV-positive samples confirmed by Western blot. Results were compared with those obtained with two third-generation anti-HIV antibody screening assays. The 236 confirmed HIV-positive samples including 3 HIV-1 subtype O and 2 HIV-2 samples were found to be positive by the 3 assays. All 128 sequential samples from 34 seroconverting patients were found to be positive using the DUO assay, including 20/20 pre-seroconversion samples (p24 antigen-positive and anti-HIV negative). The new screening assay was positive before a third-generation anti-HIV screening assay gave positive results in 14/34 patients (41%). Using the DUO assay, the mean reduction of the window period was 4 days.
Yerly
S
S
Laboratoire de Virologie, Hôptal Universitaire de Genève. sabine.yerly@hcuge.ch
Simon
F
F
Perrin
L
L
D015492:AIDS Serodiagnosis / Q000379:methods*; D015153:Blotting, Western; D015483:HIV Antibodies / Q000097:blood*; D016655:HIV Core Protein p24 / Q000097:blood*; D015658:HIV Infections / Q000175:diagnosis*; D006679:HIV Seropositivity / Q000175:diagnosis; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D012680:Sensitivity and Specificity
D015483:HIV Antibodies; D016655:HIV Core Protein p24