Objective: CD4 count is the mainstay criteria for initiation of HAART (Highly Active Anti-retroviral Therapy) and assessment of disease progression in HIV patients. CD4 percentage adds additional prognostic information. Our study was aimed to find out if Absolute Lymphocyte Count (ALC) could serve as a substitute marker for CD4 count and percentage. Methods: A total of 455 EDTA blood samples from HIV-infected patients were analyzed for their ALC, CD4 counts and CD4 percentages, over a period of 6 months, from January 2015 to June 2015 in Kasturba Hospital, Manipal. Correlation analysis of ALC with CD4 count and percentage, and receiver operating characteristic (ROC) analysis at CD4  200/µL andCD4  350/µL were conducted as proposed by WHO guidelines. Results: The male to female ratio was 2:1 and age ranged from 11 to 78 years. The median ALC was 1600/µL, median CD4 count was 258.58/µL and the median CD4 percentage was 16.4%. A strong positive correlation (Pearson coefficient, r= 0.741) was obtained between CD4 count and ALC. However, a weak positive correlation (r= 0.276) was seen between ALC and CD4 percentage. Areas under the ROC curve for ALC with CD4 count  200/µL andCD4 count  350/µL were 0.901 and 0.911, respectively, both of which showed an excellent correlation. But area under the ROC curve for ALC and CD4  20% was 0.659, which is poor in accuracy. Also, from the ROC analysis, the ALC cut offs at CD4 count  200/ µL (Sensitivity-83.87%, specificity-81.41%) and CD4 count  350/µL (Sensitivity-80.22%, specificity-86.44%) were  1450/µL and  1650/µL respectively. Conclusion: ALC has a strong correlation with CD4 count and the ALC cut offs corresponding to CD4 counts  200/µL and CD4 count  350/µL were  1450/µL and  1650/µL, respectively. But ALC did not have a good correlation with CD4 percentage. Hence, ALC is a credible alternate marker for CD4 count, but not for CD4 percentage.

Keywords: Absolute Lymphocyte Count; CD4 Count.