The "Centers for Disease Control" (CDC) recently published the guidelines for the performance of CD4+ T-cell determinations in persons with Human Immunodeficiency Virus (HIV) infection. Especially, a monoclonal antibody panel for lymphocyte immunophenotyping has been recommended i.e CD45/CD14, isotypic controls, CD3/CD4, CD3/CD8, CD3/CD19, CD3/CD56+ and/or CD16+. The authors compared, in 50 HIV+ patients, this method with the conventional method used in their laboratory i.e CD4/CD8 associated with isotypic controls. The mean values of CD4+ and CD8+ cells obtained using dual color immunophenotyping CD3/CD4 and CD3/CD8 did not differed significantly as compared with the values obtained using dual color immunophenotyping CD4/CD8. Especially, concerning CD4+ cells, differences did not exceed 4% considering each patient and 1% considering the mean values. However, in some patients, the differences between the levels of CD8+ cells obtained using the two methods were greater than 10%. These differences were due to an important percentage of CD3-CD8+ cells corresponding to NK cells. In another hand, there was no significant difference between the levels of CD4 and CD8+ cells obtained with or without correction using the gating reagent CD45/CD14. In conclusion, monoclonal antibody pannel recommended by CDC for lymphocyte immunophenotyping in HIV patients do not seem necessary in all cases. Analysis for CD4 and CD8 positive cells could be accomplish by three color simultaneous method (CD3/CD4/CD8), by first gating on CD3 positive T lymphocytes in order to eliminate both monocyte and NK cell contamination.