Pathogenetic role of HIV infection in Kaposi's sarcoma of equatorial East Africa.

Thirty residents of north-central Tanzania with various forms of Kaposi's sarcoma (KS) were evaluated. The absolute number of peripheral blood OKT4 lymphocytes in patients and Tanzanian control subjects tended to be low (in comparison with healthy young American adults), and many had inverted T4/T8 ratios. Plasma polyclonal beta- and gamma-globulin concentrations were increased in many patients with KS and in control patients in Tanzania with chronic dermatopathies, but not in African hospital employees and patients undergoing elective surgery. Three of nine patients with locally aggressive KS possessed antibodies to human T-cell lymphotropic virus type III/lyphadenopathy-associated virus (HIV), but none had evidence of the acquired immunodeficiency syndrome (AIDS) or the AIDS-related complex. Three patients with disseminated, rapidly progressive KS and high HIV-antibody titers had an immunologic and clinical picture consistent with AIDS. Two of 13 patients with the classic plaque/nodular form of KS had low plasma titers of HIV antibody, but the significance of these serologic findings is not known. The evidence suggests that HIV plays a role in the pathogenesis of some cases of KS in East Africa, but most patients with KS in East Africa have no evidence of overt immunologic deficiency or HIV infection.