Exposure to human T-lymphotropic virus type III/lymphadenopathy-associated virus and immunologic abnormalities in asymptomatic homosexual men.

Immunologic and serologic studies were done in 120 homosexual men who reportedly had no symptoms related to the acquired immunodeficiency syndrome. Forty-nine men (41%) had antibody to the retrovirus human T-lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV), and 37 (31%) had an abnormal T-cell subset ratio and other immunologic abnormalities. These abnormalities were almost exclusively confined to men seropositive for the retrovirus. Multivariate statistical analysis showed that exposure to HTLV-III/LAV was the single best predictor of T-cell (and other) immunologic abnormalities. Sexual practice, particularly receptive anal intercourse, predicted exposure to HTLV-III/LAV but was not independently related to T-cell abnormalities. The association of other microbial serologic findings with HTLV-III/LAV seropositivity or T-cell changes was a coincidental function of sexual activity. Immunologic abnormalities in asymptomatic homosexual men are mostly related to exposure to HTLV-III/LAV.