EVALUATION OF THE NUCLISENS HIV-1 QT ASSAY FOR QUANTITATION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 RNA LEVELS IN PLASMA

Nuclisens HIV-1 QT is a new version of the NASBA HIV-1 QT assay for qu antitation of human immunodeficiency virus type 1 (HIV-1) RNA in plasm a. The specificity of this assay was 100% in one laboratory and 99%-wi th nonrepeatability of the initial false positive-in another. The test was linear between 2.0 and 6.0 log RNA copies per mi. According to th e input HIV 1 RNA concentration, accuracy varied from -0.11 to +0.10 l og RNA copy per mi and precision varied from 0.66 to 0.14 log RNA copy per mi. Reproducibility decreased when the HIV-1 RNA level was near t he lower limit of quantitation of the test. HIV-1 RNA could be quantit ated by Nuclisens HIV-1 QT in 36% (laboratory 1) and 24% (laboratory 2 ) of clinical samples with HIV-1 RNA levels lower than the lower limit of quantitation by NASBA HIV-1 QT. Nuclisens HIV-1 QT was not suitabl e for measurement of RNA from clade G and group O HIV-1 strains.