[Evaluation of a panel of commercial kits for the detection of serum HIV-specific antibodies, and choice of alternative strategies for the serological diagnosis in Libreville (Gabon)].
Nine commercially available kits for the screening of serum antibodies to the human immunodeficiency virus (HIV) were evaluated with a panel of 170 serum samples from adults in Gabon. The reference procedures showed that 96 samples had no antibodies, while 74 produced antibodies to HIV-1 (n=72) or HIV-2 (n=2). The sensitivity for 2 kits was less than 99% and the specificity of 3 less than 95%. Based on the panel of Gabonese serum samples, 4 of the 9 kits met the World Health Organization (WHO) acceptability criteria: sensitivity greater than 99% and specificity greater than 95%. Three kits available in Gabon that met these criteria were finally retained: Determine HIV-1/2, Genscreen Plus HIV Ag-Ab, and Immunocomb II HIV1&2 BiSpot. Of 18 configurations of alternative diagnosis strategies for HIV infection with these three kits, some WHO strategy II configurations (2 sequential assays) and all the WHO strategy III configurations (3 sequential assays) provided the maximum accuracy in diagnosing HIV infection in Gabon (sensitivity, specificity, positive predictive value, negative predictive value of 100%). The configuration using the Determine HIV-1/2 kit as first screening assay, followed by Genscreen Plus HIV Ag-Ab as a confirmatory assay, and finally, Immunocomb II HIV1&2 BiSpot as the third assay to discriminate samples discordant with the two first assays, was best, with high accuracy and less expense. The configuration of the two sequential rapid assays, Immunocomb II HIV1&2 BiSpot followed by Determine HIV-1/2, was also very accurate and reliable, as well as easiest to carry out (no need for ELISA technology), but it was twice as expensive as the first configuration with three sequential kits. In conclusion, when the laboratory facilities are available, the sequential diagnostic strategy of two rapid assays and a combined ELISA assay constitutes the best configuration, in terms of both accuracy and cost. When laboratory facilities are unavailable, sequential use of two rapid assays constitutes a convenient and accurate configuration, but is much more expensive.
Ndjoyi-Mbiguino
Angélique
A
Département de Microbiologie, Laboratoire National de Référence IST/sida, Faculté de médecine, Université des Sciences de le Santé, BP 8302, Libreville, Gabon.
Bélec
Laurent
L
D015492:AIDS Serodiagnosis / Q000379:methods*; D000328:Adult; D003663:Decision Trees; D005260:Female; D005681:Gabon; D015483:HIV Antibodies / Q000097:blood*; D006801:Humans; D008297:Male; D011933:Reagent Kits, Diagnostic
D015483:HIV Antibodies; D011933:Reagent Kits, Diagnostic