Neurological complications of HIV/AIDS are common and not limited to opportunistic infections (see Table 32–1). All levels of the neuraxis can be involved and include the brain, meninges, nerves, and spinal cord. HIV infects macrophages and monocytes but not other nervous system cells. The brain is a repository for HIV even when peripheral HIV viral levels are low. HIV may penetrate into brain tissue as early as 2 weeks after infection. The majority of patients with advanced HIV/AIDS will live with clinically evident neurological dysfunction sometime during the course of their illness (Koppel et al. 1985). In the United States and Europe, where antiretroviral therapy is relatively available, peripheral neuropathy and HIV-associated cognitive dysfunction are the most common neurological sequelae from HIV/AIDS (McGuire 2003).