Background:
The Gen-Probe discriminatory HIV-1 (dHIV) assay is a nucleic acid amplification test utilizing transcription-mediated amplification (TMA) for the qualitative detection of HIV-1 RNA in human plasma samples. This test can be used as an aid in the diagnosis of HIV-1 infections in patients.

Objective:
To determine the analytical and clinical performance of the dHIV assay and to compare it with serology and p24 antigen results using commercially available seroconversion panels.

Method:
Clinical sensitivity was determined by testing 1042 known HIV-1 RNA positive plasma samples. Clinical specificity was determined by testing 3515 plasma specimens. Analytical sensitivity was tested using serial dilutions of negative plasma spiked with HIV-1 tissue culture supernatant. Commercially available seroconversion panels collected from plasmapheresis donors were used to compare the dHIV assay with Abbott HIV-1/2 antibody and the Abbott HIV-1 p24 antigen tests.

Result:
Clinical sensitivity was determined to be 100%. The overall clinical specificity was 99.83%. For analytical sensitivity, the dHIV assay achieved 100% detection at >100 copies/mL and 98.5% detection at 30 copies/mL. The dHIV assay detected infections with median values of 12 and 6 days earlier than the HIV-1 antibody and p24 antigen tests, respectively.


Conclusion:
The dHIV assay was shown to have high analytical and clinical performance for the detection of HIV-1 RNA in human plasma. This assay was able to detect HIV-1 RNA prior to the appearance of HIV-1 antibodies or p24 antigen in seroconversion panels.

Implications:
The Gen-Probe dHIV assay will be useful for public health HIV-1 testing programs.