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Background and objectives The performances of the new Geenius rapid confirmatory test (Bio-Rad) were evaluated with emphasis towards identifying acute infection (AHI) and discriminating HIV-1/2 in a clinical setting Study design Serum samples from individuals attending the L. Spallanzani Institute in Rome, Italy, for HIV diagnosis (one year retrospective collection), repeatedly reactive at 4th generation HIV-1/2 screening assays, confirmed with HIV-1 and HIV-2 Western blot (New LAV I and II Bio-Rad), were retested with Geenius. Results Of 6,200 samples, 406 resulted repeatedly reactive at screening, including samples from clinically confirmed AHI. New LAV I identified 378 HIV-1-positive samples. Of these, Geenius found 377 HIV-1-positive and one unclassified HIV-positive. New LAV I classified as indeterminate 18 samples, including 14 from AHI. Among these 14, Geenius results were: 12 positive, 1 indeterminate and 1 negative. Of the remaining, 2 resulted Geenius negative (false-positive screening results) and 2 HIV-2. Ten samples were New LAV I-negative (5 AHI). Geenius results were: 1 (AHI) positive and 9 negative. Geenius detected 110 additional positive samples with no p31 reactivity with respect to New LAV I, with an almost similar prevalence of low avidity samples. Geenius confirmed 3 out of 4 HIV-2 infections identified by New LAV II (one coinfected with HIV-1), while rated as HIV-1 the remaining sample, classified as coinfection by New LAV I and II. Conclusions Geenius allows fast, sensitive and accurate confirmation of HIV serodiagnosis, including AHI and HIV-2 infections. The high sensitivity, in particular towards AHI, could avoid additional sampling and molecular tests.

We compared two commercial assays for HBV DNA quantitation, Versant HBV 3.0, System 340 (bDNA; Bayer Diagnostics) and COBAS AmpliPrep-COBAS TaqMan HBV Test (TaqMan; Roche Diagnostics). Analytical sensitivity, calculated on WHO International Standard, predicted 95% detection rate at 11.4 and 520.2IU/ml for TaqMan and bDNA, respectively. Specificity, established on 50 blood donor samples, was 100% and 84% for TaqMan and bDNA, respectively. When using clinical samples, HBV DNA was detected by TaqMan in 21/55 samples negative to bDNA. Mean values of HBV DNA obtained with bDNA were higher than those obtained with TaqMan (4.09log(10)+/-1.90 versus 3.39log(10)+/-2.41, p0.001), and 24.4% of samples showed differences in viral load values0.5log(10), without association with HBV genotype. There was a good correlation for HBV DNA concentrations measured by the two assays (r=0.94; p0.001) within the overlapping range, and the distribution of results with respect to relevant clinical threshold recently confirmed (20,000 and 2000IU/ml) was similar. Approximately 50% of samples with low HBV DNA, appreciated by TaqMan but not by bDNA, were successfully sequenced in pol region, where drug resistance mutations are located.

We used a molecular panel, targeting seven enteric viruses, to explore the advantage of using molecular methods to establish the etiology of enteric diseases and to evaluate the prevalence of enteric viruses in asymptomatic human immunodeficiency virus-infected patients. This approach favors rapidity and sensitivity of laboratory diagnosis of viral enteric syndromes.