Comparison of levels of human immunodeficiency virus type 1 RNA in plasma as measured by the NucliSens nucleic acid sequence-based amplification and quantiplex branched-DNA assays

This study compared levels of human immunodeficiency virus type 1 RNA in pl asma as measured by the Quantiplex branched-DNA and NucliSens nucleic acid sequence-based amplification assays. RNA was detectable in 118 of 184 sampl es (64.13%) by the Quantiplex assay and in 171 of 184 samples (92.94%) by t he NucliSens assay. Regression analysis indicated that a linear relationshi p existed between the two sets of values (P < 0.0001), although the Quantip lex and NucliSens values were significantly different (P < 0.001), with the NucliSens values being approximately 0.323 log higher, Spearman correlatio n analysis indicated that the overall changes in patient viral load pattern s were highly correlative between the two assays: r = 0.912, P < 0.0001, Th e lower limits of sensitivity were determined to be approximately 100 copie s/ml and 1,200 to 1,400 copies/ml for the NucliSens and Quantiplex assays, respectively.