Mycobacterium avium complex infection and AIDS: advances in theory and practice.

The role of disseminated infection with the Mycobacterium avium complex (MAC) in the natural history of AIDS has been controversial. It is now clear that this complication of immunosuppression induced by human immunodeficiency virus type 1 (HIV-1) has a major impact upon the quality of life and duration of survival of patients with advanced HIV-1 infection. Progress has been made in our understanding of the bacteriology, pathogenesis, prevention, and treatment of MAC infection. Drs. Constance Benson and Jerrold Ellner (of Rush Medical College in Chicago and Case Western Reserve University in Cleveland, respectively) have led the effort by the AIDS Clinical Trials Group to develop new methods of managing this serious complication of advanced HIV-1 infection. In this AIDS commentary they review our current knowledge of MAC organisms and the clinical problems resulting from infection with these mycobacteria.