[Quantitation of human immunodeficiency virus type 1 RNA by ultrasensitive method in the analysis of samples with low...

With the introduction of combination therapy to the patients with Human Immunodeficiency Virus Type 1(HIV-1) infection, HIV-1 RNA levels in plasma have been reduced, frequently to less than limit of quantitation(400 copies/ml). To achieve enhanced sensitivity, a modified specimen preparation procedure that allows the quantitation of plasma HIV-1 RNA levels as low as 50 copies/ml was developed. Of 67 samples with less than 400 copies/ml of HIV-1 RNA by standard method, 39(58.2%) were not detected by the "ultrasensitive" method. Among 5 samples obtained from patients who were treated with 2 nucleoside reverse transcriptase inhibitors, 4 samples still had detectable copies of HIV-1 RNA. Those suggest that the ultrasensitive assay for HIV-1 RNA has advantage for clinical practice.