Comparison by race of total serum IgG, IgA, and IgM with CD4+ T-cell counts in North American persons infected with the human immunodeficiency virus type 1.

European patients with human immunodeficiency virus type 1 (HIV-1) infection have been reported to have lower titers of anti-p24 antibody than Central African HIV seropositive patients. Recently, black HIV positive patients in the United States were reported to be more likely to have detectable anti-p24 antibodies, less p24 antigenemia, and higher combined serum immunoglobulins than white HIV positive patients. We measured individual total serum immunoglobulins in 853 HIV positive patients (94% male; 58% white and 42% black) on their initial medical evaluation and compared them with CD4+ T-cell counts. Blacks had notably higher IgG levels (p = 0.001) across the entire spectrum of CD4+ T-cell counts. Serum IgM levels were slightly higher in blacks. IgA levels were not significantly different between the races, although the trend (p = 0.006) was toward higher levels in whites. We also measured these three serum immunoglobulins in 60 HIV seronegative, healthy blood donors (30 black and 30 white). In this control group, blacks had statistically higher IgG and IgA levels than whites. A review of the literature prior to the HIV/acquired immune deficiency syndrome epidemic also supports the view that racial differences in IgG levels are not specific for HIV infection. We speculate that racial differences in humoral immunity, independent of geography or strain of HIV, may account for differences in anti-HIV antibody levels and HIV antigenemia.