Parasitic infection
A number of parasitic infections may involve the central nervous system. Immunosuppression (including HIV) increases susceptibility 1).
CNS parasitic infections include:
Those that potentially involve neurosurgical intervention
Cysticercosis: see Neurocysticercosis.
Toxoplasmosis: may occur as a congenital TORCH infection, or in the adult usually with AIDS.
Toxoplasma gondii is an obligate intracellular protozoan that is ubiquitous but does not cause clinical infection except in immunocompromised hosts. Histologic features: necrosis containing 2–3 nm tachyzoites (cysts)
Amebiasis: ≈ exclusively Naegleria fowleri.
1)
Walker M, Kublin JG, Zunt JR. Parasitic central nervous system infections in immunocompromised hosts: malaria, microsporidiosis, leishmaniasis, and African trypanosomiasis. Clin Infect Dis. 2006; 42: 115–125