USEFULLNESS OF TOTAL LYMPHOCYTE COUNT (TLC) AS A ANALYTICAL MARKER FOR CD4 T CELL COUNT IN HIV INFECTED PATIENTS: A HOSPITAL BASED STUDY

Dr. Subhash Chand*, Dr. Pravesh Agarwal and 3Dr. Ajay Kumar

ABSTRACT

AIDS is not a single disease but it is the manifestation of a group of diseases, therefore it is appropriately called as syndrome. Due to infection the immune mechanism breaks down making the host vulnerable to overwhelming fatal infections. HIV primarily causes progressive qualitative and quantitative deficiency of a subset of T lymphocytes called CD4 T cells. CD4 T cell count has become the most quoted single index of cell mediated immunity in HIV infected patients. However, providences in resource-constraint settings may not have access to the well established laboratory measurement, or the cost may be prohibitive resulting in the need for an alternative and effective surrogate marker. Hence, total lymphocyte count (TLC) was evaluated as a probable surrogate marker for CD4 T cell count in this study. Aims: To evaluate the correlation of CD4 T cell count with the Total Lymphocyte Count in HIV infected patients and to find out a critical value of TLC which can predict a CD4 T cell count less than 200/cmm, for the initiation of antiretroviral therapy. Materials and Methods: The prospective study was conducted on the 40 HIV positive patients admitted in the Department Medicine over a period of one year at Indira Gandhi Medical College and Hospital (IGMC) Shimla. The Complete Blood count, CD4 T cell count and Total Lymphocyte count were measured. The Sensitivity, specificity and positive predictive value of Total Lymphocyte count computed to find out CD4 T cell count <200/cmm. using spearman, s rank correlation. Results: A positive correlation between Total Lymphocyte count and CD4 T count was observed in our study. The Total Lymphocyte count of 1700/cmm was able to predict CD4 T cell count <200/cmm with highest sensitivity (72%), specificity (100%) and positive predictive value (100%). Conclusions: The Total Lymphocyte count 1700 cells/ cmm was the best predictor of CD4 count <200 cells/ cmm and hence TLC can become a reliable marker for the initiation of Antiretroviral therapy resource limited country.

Keywords: Total lymphocyte count, CD 4 T cell, antiretroviral therapy.