The objectives of this study are todescribe the clinical history, treatment, pathology, and imagingof amoebic encephalitis and illustrate some of them.

Primary amebic encephalitis and granulomatous amebic encephalitis arecentral nervous system infections caused by free-living amebae. They have distinctive epidemiology, pattern of presentation, clinical course, pathology, and imaging findings. Granulomatous amoebic encephalitis (GAE), also referred to ascerebral amoebiasis, is caused by free-living amoebae such as Acanthamoeba spp (main cause), Balamuthia mandrillaris and Sappinia pedata .Itis a distinct clinical syndrome toprimary amoebic...

Pathologically, the macroscopic appearance in GAE is one of focal edema of the cerebral hemispheres. Multifocal parenchymal lesions with involvement of posterior cranial fossa structures, the diencephalon, and the thalamus are seen. The presence of trophozoites and cysts, along with a chronic granulomatous reaction containing multinucleated giant cells, is characteristic. Microscopically, there is evidence of leptomeningitis, most prominent adjacent to the parenchymal lesions. There may be...

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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