Use of virologic markers in clinical practice

A number of virologic and immunologic markers, including serum human immunodeficiency virus (HIV)-1 p24 antigen levels, quantitative HIV-1 microculture of plasma or peripheral blood mononuclear cells, and CD I cell counts, have been used over the past decade to monitor progression of HIV infection. Although these markers are useful, they have not provided a reliable means of assessing prognosis at all stages of the disease or response to antiretroviral treatment. New molecular techniques are now available that measure viral load in HIV-infected patients by detecting and quantifying virion-associated RNA circulating is plasma. These plasma HIV-I RNA levels appear to correlate with the clinical disease stage and reflect the response to antiretroviral treatment. Because recent studies have demonstrated that baseline plasma HIV-1 RNA levels and changes in these levels are predictive of clinical outcome, it is strongly recommended that these markers be measured routinely and used as a guide in the management of all patients with HIV disease.