Cellular and serological markers of disease activity in Indian patients with HIV/AIDS

There has been an exponential rise of HIV positive patients as observed at the surveillance center of Nehru Hospital. Most patients are poor and cannot afford repeated viral load assays. Therefore, there is a need to identify cost effective and reliable surrogate markers of disease activity. In the present study absolute number of CD4 cells, beta2 micro-globulin, circulating nucleosomes were studied in 30 patients of AIDS, 30 seropositives and 30 healthy controls. In addition viral load, P-24 assay, and TNFR-II assays were done in seropositive and AIDS patients. The mean CD4 cells in patients with AIDS were 69.66 +/- 68.25 mm3 while in seropositives values was 370 +/- 201.29 mm3. The mean CD4 cells in healthy controls were however 690 +/- 198 mm3. The differences in all the groups were highly significant (p<0.001). The mean CD4 values in Indians are significantly lower than reported from the west. The lower number of CD4 cells in healthy population is interpreted to be due to immune activation. The CD8 cell number in controls was 650 +/- 207 mm3 this figure is also higher than that observed in the west. P-24 assay failed to delineate between seropositives and patients with AIDS. Although, beta2 microglobulin levels were significantly higher in AIDS than in seropositives and higher in seropositives than in controls yet with the best possible cut off, it had a sensitivity of only 70% in delineating the two conditions. The correlation between CD4 cells and viral load was more significant when the CD4 cells were below 200 mm3. Five out of 30 patients with a CD4 of 300-600 mm3 had a viral load of over 1 x 10(5) cop/ml. The difference in TNF R-II levels between seropositives and AIDS was however more impressive. With a cut off of 550 pg/ml it had a sensitivity of 95% in delineating HIV from AIDS. It is concluded that a combination of absolute number of CD4 cells and TNF R-II assay along with clinical evaluation may be used to monitor therapy in resource poor countries where frequent viral load assay is unaffordable.