Validity of existing CD4+ classification in north Indians, in predicting immune status

The CD4 lymphocyte count had ethnic variability as observed in many studies. In populations with CD4 counts inherently lower than in the West, the Center for Disease Control and Prevention (CDC) classification system of HIV-infected individuals may not be appropriate. As there is no such criterion currently available for ethnic north Indians HIV-patients, we undertook this study to assess the applicability of the western case definition in north Indian HIV patients.

The CD4 counts of 40 normal and 376 HIV-infected north Indian adults attending to ID clinic, SS hospital, Varanasi were estimated by flowcytometry. The mean CD4 counts were estimated and compared between CDC groups A, B and C and controls. Receiver operator characteristic (ROC) curves were generated to determine the cut-off that correlated best with clinical staging for this population.

For CDC groups A, B and C, the mean CD4 counts/mul (upper limits of the 95% CI) were 380.3, 249.2 and 120.9, while the mean CD4 levels in healthy volunteers was 818.4.

The mean CD4 count among normal north Indians is significantly lower than that in the western population and parallels that of the Chinese. When categorized based on the Center for Disease Control and Prevention (CDC) classification system, the mean CD4 counts in HIV-infected individuals was lower. Categories of CD4 counts >280, 120-280 and < or =120 cells/microl correlate better with disease progression among HIV-infected individuals. A longitudinal study is required before guidelines for the India population can be devised.