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An Acute Case of Granulomatous Amoebic Encephalitis-Balamuthia mandrillaris Infection
Kentarou Takei1, Masaya Toyoshima1, Masashi Nakamura1
1Department of Neurology, Osaki Citizen Hospital, Japan.
Abstract:
A 74-year-old woman who exhibited drowsiness was referred to our hospital. Enhanced head magnetic resonance imaging (MRI) revealed multiple ring-enhancing lesions and lesions showing partial mild hemorrhaging. The patient gradually progressed to a comatose condition with notable brain deterioration of unknown cause on follow-up MRI. On day nine, the patient inexplicably died, although brain herniation was suspected. Autopsy and histopathology revealed numerous amoebic trophozoites in the perivascular spaces and within the necrotic tissue. Brain immunostaining tested positive for Balamuthia mandrillaris. Infection due to free-living amoeba is rare in Japan; however, it may increase in the near future due to unknown reasons.
Insights
A rare case of Balamuthia mandrillaris infection caused severe brain deterioration and death in a 74-year-old woman. Autopsy confirmed amoebic trophozoites, highlighting the potential for increased free-living amoeba infections.
Area of Science:
- Neurology
- Infectious Diseases
- Pathology
Background:
- Free-living amoeba infections are rare but can cause severe neurological disease.
- Balamuthia mandrillaris is an opportunistic pathogen.
- This case highlights a rare infection in Japan.
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