The objectives of this study are todescribe the clinical history,
and imagingof amoebic encephalitis and illustrate some of
Primary amebic encephalitis and granulomatous amebic encephalitis arecentral nervous system infections caused by free-living amebae.
They have distinctive epidemiology,
pattern of presentation,
and imaging findings.
Granulomatous amoebic encephalitis (GAE),
also referred to ascerebral amoebiasis,
is caused by free-living amoebae such asAcanthamoeba spp(main cause),Balamuthia mandrillarisandSappinia pedata.Itis a distinct clinical syndrome toprimary amoebic meningoencephalitis(PAM),
which is an acute illness that presents like a severe bacterial meningoencephalitis and is caused byNaegleria fowleri.
GAE has a gradual and highly variable subacute-chronic course over weeks and months....
Findings and procedure details
the macroscopic appearance in GAE is one of focal edema of the cerebral hemispheres.
Multifocal parenchymal lesions with involvement of posterior cranial fossa structures,
and the thalamus are seen.
The presence of trophozoites and cysts,
along with a chronic granulomatous reaction containing multinucleated giant cells,
there is evidence of leptomeningitis,
most prominent adjacent to the parenchymal lesions.
There may be severe necrotizing angitis.
GAE is diagnosed by identifyingAcanthamoebatrophozoites or cysts in CSF/brain biopsy.
Cultures of brain tissues or CSF...
Imaging features of amebic encephalitis are sometimes non-specific and
have only rarely been described in previous literature.
The description of the case and themost frequent imaging findings will help the unsuspectingradiologists to familiarize with the diverse spectrum of neuroimaging findings.
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