November 17, 2008
47-year-old man with leukemia now presenting with signs of infection for several weeks.
Granulomatous Amebic Encephalitis
- Onset is slow and insidious and develops over several weeks.
- Cerebral hemispheres are most affected.
- Acanthamoeba infecting the CNS are not readily found in CSF. Pathogenic and opportunistic amebae are aerobic eukaryotic, free-living organisms in nature only occasionally invading a host.
- Granulomatous amebic encephalitis is an opportunistic infection, primarily in patients with HIV/AIDS or those chronically ill, diabetic, or after organ transplantation. Patients do not have a recent history of exposure to recreational freshwater.
- Amebic trophozoites and cysts are usually scattered throughout the brain. Aside from granulomatous inflammation, brain blood vessels may be thrombosed, show fibrinoid necrosis of their walls, and be cuffed by neutrophils, amebic trophozoites and cysts.
