The AIDS dementia complex: some current questions.

The acquired immunodeficiency syndrome (AIDS) dementia complex (ADC) commonly complicates the course of human immunodeficiency virus (HIV) infection and AIDS. Although many of its clinical aspects have recently been brought into clearer focus, and pathogenetic evidence has accrued implicating direct HIV brain infection, there remain a number of fundamental aspects of ADC and HIV nervous system infection that require clarification. These include clearer definition of the clinical syndrome and its variants; development of instrumentation for diagnosis and monitoring the disorder; definition of the epidemiology and natural history of both central nervous system HIV infection and ADC, which may seemingly be discordant; and understanding of both the viral pathogenesis and the biology of resultant brain dysfunction. Elucidation of these fundamental issues will enhance rational development and evaluation of therapy.