Amebic infections of the central nervous system

Abstract The report of death of a person from amebic meningoencephalitis, the proverbial “brain-eating ameba,” Naegleria fowleri, acquired in a state park lake in Iowa in July 2022 has once again raised the seasonal alarms about this pathogen. While exceptionally rare, its nearly universal fatality rate has panicked the public and made for good copy for the news media. This review will address free-living ameba that have been identified as causing CNS invasion in man, namely, Naegleria fowleri, Acanthamoeba species, Balamuthia mandrillaris, and Sappinia diploidea (Table 1). Of note, several Acanthamoeba spp. and Balamuthia mandrillaris may also be associated with localized extra-CNS infections in individuals who are immunocompetent and disseminated disease in immunocompromised hosts. These ameba are unique from other protozoa in that they are free-living, have no known insect vector, do not result in a human carrier state, and are typically unassociated with poor sanitation. Table 1Free-living ameba that have been identified as causing CNS invasion in man, namely, Naegleria fowleri, Acanthamoeba species, Balamuthia mandrillaris, and Sappinia diploideaEntityPathogenic amebaPredisposing disordersPortal of entryIncubation periodClinical featuresRadiographic findingsCSF findingDiagnostic measuresPrimary amebic meningoencephalitisNaegleria fowleri; N. australiensis; N. italicaPreviously healthy children or young adultsOlfactory epithelium2–14 days (average 5 days)Headache, fever, altered mental status, meningeal signs; seizuresBrain edema; meningeal enhancement; hydrocephalus; basal ganglia infarctionsIncreased opening pressure; neutrophilic pleocytosis (~ 1000 cells/cu mm); low glucoseBrain biopsy, CSF wet prep, IIF culture or PCRGranulomatous amebic encephalitisAcanthamoeba spp.; Balamuthia mandrillaris; Sappinia diploideaTypically, immunocompromised individualSkin sinuses; olfactory epithelium respiratory tractWeeks to monthsHeadache; altered mental status seizures, focal neurological findingsFocal parenchymal lesions with edema; hemorrhagic infarctions; meningeal enhancementGenerally, LP contraindicated; when performed lymphocytic pleocytosis; increased protein; low glucoseBrain biopsy, CSF culture, wet prep, IIF, or PCRIIF indirect immunofluorescence, LP lumbar puncture, PCR polymerase chain reaction.

Medienart:	Artikel

Erscheinungsjahr:	2022
Erschienen:	2022

Enthalten in:	Zur Gesamtaufnahme - volume:28
Enthalten in:	Journal of neurovirology - 28(2022), 4-6 vom: 13. Sept., Seite 467-472

Sprache:	Englisch

Beteiligte Personen:	Berger, Joseph R. [VerfasserIn]

Links:	Volltext [lizenzpflichtig]

Themen:	Ameba Granulomatous amebic encephalitis Primary amebic meningoencephalitis

Anmerkungen:	© Journal of NeuroVirology, Inc. 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

doi:	10.1007/s13365-022-01096-x

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PPN (Katalog-ID):	OLC2080201077