Contrasting quantitative alterations in CD4+ and CD8+ lymphocytes in HIV-infected African Americans compared with the Caucasian population.

Enumeration of circulating T lymphocytes is crucial in the investigation of AIDS and related conditions. The single best measure of disease progression and prognosis is the absolute number of helper/inducer T lymphocytes in the peripheral blood. Although the phenotypic identification of a particular subset reflects no direct information on the function of the population, the information provided by the analysis furnishes new insight regarding racial differences in the immune deficiency associated with AIDS. The severity of the HIV illness in the African American population, as reflected by a decrease in the absolute number of circulating CD4+ lymphocytes, was marked compared to the Caucasian population with AIDS. Consequently, the CD4/CD8 ratio was lower in the African American HIV+ population. A higher level of activated mononuclear lymphocytes and NK cells in this population may indicate active disease. The incidence of life-threatening opportunistic infections such as PCP was greater in the adult/adolescent African Americans compared to Caucasians. In contrast, PGL was found more frequently in the Caucasian participants. Although the rate of HIV infection in the adult/adolescent African American population was not different from population estimates for the area under study, the incidence in the pediatric African American population was twice the population estimates for the race. This increased rate occurred in the parent-at-risk as well as in the hemophiliac group.