Chronic Meningitis.

Chronic meningitis may be caused by a large number of infectious agents, including spirochetes (Treponema pallidum, Borrelia burgdorferi), Mycobacterium tuberculosis, and fungi (primarily Cryptococcus neoformans). The incidence of these specific causes of chronic meningitis has been impacted since the advent of HIV infection, and new information is also available on how this epidemic has affected populations in developing countries of the world. In the area of diagnostics, the development of polymerase chain reaction has been a major advance that has increased our capabilities for identifying etiologic agents (such as M. tuberculosis) that are difficult to culture. Finally, the management of patients with chronic meningitis has evolved, and the availability of new antifungal agents and adjunctive strategies has changed the approach to the patient with cryptococcal meningitis.