Challenges to the diagnosis and management of HIV dementia.

: Although it has been evident since the early days of the HIV epidemic that a dementing illness often accompanies HIV infection and that the virus invades the nervous system soon after systemic infection, the clinical syndrome has evolved with the introduction of antiretroviral therapy. Milder forms of cognitive impairment with a variable course, evident at higher CD4+ cell counts, are now more frequently seen. Furthermore, these patients often have other comorbidities such as drug abuse, hepatitis C virus infection, depression, and those associated with aging as confounding factors. The antiretroviral drugs may themselves be toxic or cause an immune reconstitution syndrome that needs to be distinguished from HIV dementia. The treating physician thus faces several new challenges in the diagnosis and treatment of a patient with HIV infection who presents with cognitive impairment. In this article, we provide a systematic approach to addressing each of these issues and guidelines for management of these patients. We also discuss the latest experimental approaches and the clinical trials being conducted for the better management of this population.