Use of surrogate markers to predict the HIV disease stage and time to initiate antiretroviral therapy in developing countries.

CD4 counting is the standard method for determining eligibility for antiretroviral therapy (ART) and HIV disease progression, but it is not widely available in developing countries. The aim of this study was to correlate the levels of beta-2 microglobulin and total lymphocyte count (TLC) with CD4 counts for monitoring disease progression and identify patients who require ART. The authors measured CD4 T-cell counts, TLC, and beta-2 microglobulin levels in 119 HIV seropositive patients. There was a significant negative correlation between CD4 counts and beta-2 microglobulin levels and significant positive correlation between TLC and CD4 counts. Taking a TLC cutoff of < or = 1600 and beta-2 microglobulin levels > or = 3.5 mg/l, the authors could identify 90.4% of patients with CD4 count < or = 200 cells/microl. These assays may allow reduction in the annual number of CD4 cell evaluation and the cost associated with monitoring the immune status of HIV-positive patients.