CD4+ lymphocyte count (CD4+ LC) is a widely used marker of Human Immunodeficiency Virus (HIV) immune impairment. Physiological lymphocytosis is frequently encountered in Africans. Therefore, we tried to determine if given CD4+ LC levels are of similar significance in European versus African HIV-infected individuals. Lymphocyte phenotyping of 750 HIV-infected adults was retrospectively analyzed. Three hundred and seventy patients were consecutively selected in Paris, France; 185 in Abidjan, Côte d'Ivoire; and 195 in Bobo-Dioulasso, Burkina Faso. In the three settings, lymphocyte phenotyping was performed by flow cytometry using similar protocols. Data from Abidjan and Bobo-Dioulasso were combined on the basis of geographic proximity and contrasted with those from Paris. Geometric mean levels of Total Lymphocyte Count (TLC), CD4+ LC, CD8+ lymphocyte count (CD8+ LC), and CD4:CD8 ratio, adjusted for percentage of CD4+ T-cells (%CD4+), were compared between Africans and Europeans. For a given %CD4+, TLC and CD4+ LC but not CD8+ LC tended to be about one third higher in West African than in French adults (p < 0.0001). Approximate equivalencies of absolute CD4+ counts in French and West African HIV-infected adults suggest that where thresholds of 200 and 500 CD4+ cells/microliter are applied in Europe, it might be appropriate to apply a threshold of approximately 250 and 700 CD4+ cells/microliter in West Africa, respectively. Establishing indicators of progression of HIV infection with locally appropriate thresholds may represent important steps toward improvement of HIV disease management in Africa.
PIP: CD4+ T-lymphocyte count (CD4+ LC) is a widely used marker of HIV immune impairment. The authors explored whether given CD4+ LC levels have the same significance in European HIV-infected individuals as they do in similarly infected Africans. 370 HIV-infected adults were consecutively selected in Paris, France, 185 in Abidjan, Cote d'Ivoire, and 195 in Bobo-Dioulasso, Burkina Faso, to undergo retrospective lymphocyte phenotyping using flow cytometry. Data from Abidjan and Bobo-Dioulasso were combined on the basis of geographic proximity and contrasted with those from Paris. Geometric mean levels of total lymphocyte count (TLC), CD4+ LC, CD8+ LC, and CD4:CD8 ratio, adjusted for the percentage of CD4+ T-cells, were compared between Africans and Europeans. For a given percent CD4+, TLC and CD4+ LC, but not CD8+ LC, tended to be about one-third higher in West African than in French adults. Approximate equivalencies of absolute CD4+ counts in French and West African HIV-infected adults suggest that where thresholds of 200 and 500 CD4+ cells/mcl are applied in Europe, thresholds of approximately 250 and 700 CD4+ cells/mcl may be more suitable in West Africa. Establishing indicators of the progression of HIV infection with locally appropriate thresholds may lead to the improved management of HIV disease in Africa.