Amebae can invade the central nervous system (CNS), causing rare but fatal infections. Seizures can complicate any of the ameba-caused clinical syndromes. Epidemiologic data are inadequate to comment on seizure incidence.
A few principal amebic parasites can cause CNS infection:
||Acanthamoeba or Hartmannella
||Widespread distribution, tropics more virulent
||Southeastern United States
||Chronic illness, immunosuppression
||Entamoeba brain abscess (resembles brain abscess, tumor, chronic meningitis, or a combination of these)
||Primary amebic meningoencephalitis (acute meningoencephalitis)
||Granulomatous amebic encephalitis (resembles brain abscess, tumor, chronic meningitis, or a combination of these)
|Acute meningitic symptoms
|Subacute-chronic meningitic symptoms
Wet mount: motile trophozoites
Wet mount: sluggish organisms
CSF = cerebrospinal fluid; N = neutrophils; L = lymphocytes; WBC = white blood cell.
Table adapted from MJ Aminoff, DA Greenberg, RP Simon. Clinical Neurology. Stamford, CT: Appleton & Lange, 1996;37; and DT Durack. Amebic infections. In WM Scheld, RJ Whitley, DT Durack (eds), Infections of the Central Nervous System. Philadelphia: Lippincott–Raven, 1997;831–844.
Adapted from: Goldstein MA and Harden CL. Infectious states. In: Ettinger AB and Devinsky O, eds. Managing epilepsy and co-existing disorders. Boston: Butterworth-Heinemann; 2002;83-133.
With permission from Elsevier (www.elsevier.com).
Reviewed and revised March 2004 by Steven C. Schachter, MD, epilepsy.com Editorial Board.