Modified Boosted - p24 Antigen can Predict HIV-1 RNA Viral Load (Ampiclor HIV-1 Monitor)

Abstract

Objective: To evaluate the predictive value of HIV-1 RNA viral load (Ampiclor) in log-copies per ml by each level of modified boosted-p24 antigen in log-fg per ml.
Methods: 283 plasma samples were collected and blindly determined HIV-1 RNA Amplicor Monitor, Roche as a standard test with modified boosted p24 antigen assay. Likelihood ratio positive analyses of multiple levels of p24 were calculated as well as the post-test probability in predicting the amount of virus (log-copies/ml)
Results: Subjects were between 18 to 73 years old with the range of virus 1.75 to 5.92 log-copies per ml. By the calculation of likelihood ratio positive and positive predictive value, it was demonstrated that modified boosted p24 antigen (Ag in log-fg per ml) might predict the viral load (VL) in log-copies per ml as follow:

     Ag 2.0-3.0 log-fg per ml corresponding to 2.0 or lower log-copies per ml VL
     Ag 3.0-3.5 log-fg per ml corresponding to 2.5 or lower log-copies per ml VL
     Ag 3.5-4.0 log-fg per ml corresponding to 3.5 or lower log-copies per ml VL
     Ag 4.0-overlog-fg per ml corresponding to 4.5 or lower log-copies per ml VL

Conclusions: In countries where financial resources are limited, modified p24 antigen may be clinically applied in antiretroviral management program, instead of HIV-1 RNA Amplicor Monitor, Roche.