Correlation between Total Lymphocyte Count, Hemoglobin, Hematocrit and CD4 Count in HIV/AIDS Patients

Lymphocyte CD4count, a standard laboratory test for staging of HIV infection, is expensive and unavailable in resource-restricted countries. Total lymphocyte count (TLC) and hemoglobin (Hb) are recommended as simple & inexpensive surrogates. The aim of this study was to assess the correlation, sensitivity and predictive power of these parameters as substitutes for CD4 count. One hundred HIV patients enrolled in this analytic descriptive study in Ahvaz, a city in the South of Iran, from 2005 to 2006. They were tested for CD4 count, TLC, Hb, and hematocrit (Hct). The cutoffs were determined as: 200 cells/μL, 1200 cells/μL, 12 g/dl and 30%, respectively. We used Sys Max SE 9500 for CBC and Flow cytometry for CD4 count. The correlation coefficient established correlation between values. Sensitivity, specificity and positive predictive values were calculated. 2 females (%2) and 98 males (%98) of the mean age of 325 years were studied. 87 cases (%87) were IV drug users, the majority having a history of imprisonment. The mean CD4 count, TLC, Hb and Hct were 279±225, 2102±1250, 10.7±2.4 and 30.4±9.0, respectively. A strong correlation was observed between CD4 count and TLC (R = 0.645, P = 0.001), but no correlation was seen between CD4 count and Hb or Hct (R= 0.451, P=0.056 and R= 0.375, P=0.816 respectively). This study shows that TLC is a suitable surrogate marker for CD4 count. Hb and Hct are of limited value in predicting CD4 counts and should not be substituted for CD4counts. © 2009 Tehran University of Medical Sciences. All rights reserved. Acta Medica Iranica 2009; 47(1): 1-4.