RATES OF P24 ANTIGENEMIA AND VIRAL ISOLATION IN COMPARABLE WHITE AND BLACK HIV-INFECTED SUBJECTS

Objective: To determine the relative frequencies of HIV-1 p24 antigen and culture positivity in white and black patients. Design: Volunteers in the US military's HIV natural history study were 46% white, 44% bl ack, 7% Hispanic and 3% other. Focusing on the comparable groups of wh ites and blacks, a retrospective analysis was performed of the results of virologic assays collected over a 2-year period. Methods: p24 anti gen was quantitated in sera with and without immune complex dissociati on (ICD); viral isolation was performed by coculture of peripheral blo od mononuclear cells. Results: Results of the two virologic assays wer e very similar in the two racial groups, both overall and after strati fication by CD4 cell count. As reported previously, the concentration of serum immunoglobulin G was found to be greater in black than white subjects. In contrast to results with ICD, sera tested without ICD res ulted in differing (higher) rates of antigenemia in whites than blacks (P=0.002). Conclusions: The frequencies of p24 antigen and culture po sitivity were found to be independent of race. Previously observed rac ial differences in antigen positivity were likely to be due to more ex tensive antibody binding in blacks than in whites.