TOTAL LYMPHOCYTE COUNT AS AN ALTERNATIVE TO CD4 COUNT IN MANAGMENT OF HIV/AIDS PATIENTS

Abstract

Background: Initiation and monitoring of ART are based on CD4+ count which is however, costly and often inaccessible in resource restricted communities. TLC (total lymphocyte count) has been advocated over the years as a marker for progression of HIV. The aim of the study was to find relationship between CD4 count and TLC and to determine whether TLC can be used as a surrogate marker for CD4 counts.

Methods: Descriptive/Cross-sectional study was conducted at department of Pathology Allama Iqbal Medical College Lahore.  A total of 106 HIV subjects were included. Blood samples were analyzed for TLC and CD4 counts. Pearson’s correlation between TLC and CD4 count was evaluated. Receiving Operating Characteristic (ROC) was used to calculate sensitivity, specificity, positive and negative predictive values for various cut-off points of TLC to predict CD4 count ≥500/µl, 200–499/µl, <350/µl and < 200/µl.

Results: A TLC of ≤1400/µl had a maximum sensitivity of 83.3% and specificity 71.1% for predicting CD4 cell count of < 200/µl. The best TLC cut-off for predicting CD4 count <350/µl with a maximum sensitivity of 81.5% and specificity 76.4% was ≤2200 /µl. A CD4 count ≥500/µl was predicted with maximal sensitivity of 88% and specificity of 73.2% at TLC cut-off       >2200 /µl. A positive Pearson’s correlation coefficient (r) of 0.6623 (p < 0.0001) was noted when TLC and CD4 count were analysed. Area Under Curve of different groups was high (close to 1) that makes TLC an ideal alternate to CD4 count.

Conclusion: We suggest cut-off TLC ≤1400/μl for anticipating CD4 counts < 200/μl to initiate ART in resource-poor settings.

Key Words: CD4 count, Total lymphocyte count, HIV