Common neurologic complications of HIV-1 infection and AIDS.

Complications of human immunodeficiency virus type 1 infection and acquired immunodeficiency syndrome may involve any level of the central or peripheral nervous system. Acute encephalitis, aseptic meningitis and acute demyelinating polyneuropathy may occur early in the course of HIV infection, while dementia, central nervous system-related cancer, opportunistic infections and autonomic neuropathy typically present later. Headache and mental status changes are common early manifestations of central nervous system involvement. Most severe headaches are related to an identifiable cause, including a mass lesion, opportunistic cerebral infection and medication side effect. Memory deficits, concentration difficulties and abnormalities on mental status testing may represent early AIDS dementia complex (HIV encephalopathy), the most common neurologic complication. In patients with AIDs, the differential diagnosis of cerebral mass lesions on computed tomography or magnetic resonance imaging includes cerebral toxoplasmosis, tuberculous or fungal abscess, focal viral encephalitis, metastatic resonance imaging includes cerebral toxoplasmosis, tuberculous or fungal abscess, focal viral encephalitis, metastatic Kaposi's sarcoma and primary CNS lymphoma. Peripheral neuromuscular disease, including distal symmetric polyneuropathy, autonomic neuropathy, and HIV and chronic zidovudine myopathy, affects 15 to 40 percent of all persons with HIV infection or AIDS.