[Central nervous system infection by free-living amebas: report of 3 Venezuelan cases]

R Rodríguez1, O Méndez, O Molina

  • 1Facultad de Medicina, Universidad del Zulia, Venezuela.

Revista De Neurologia
|July 11, 1998
PubMed
Abstract

Insights

Free-living amebas can cause rare but severe central nervous system infections like Primary Amebic Meningoencephalitis (PAM) and Granulomatous Amebic Encephalitis (GAE). These infections are likely underdiagnosed due to limited awareness and autopsy rates.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Parasitology

Background:

  • Central nervous system (CNS) infections by free-living amebas are rare, with fewer than 400 cases reported.
  • Two main clinical forms exist: Primary Amebic Meningoencephalitis (PAM) caused by Naegleria fowleri and Granulomatous Amebic Encephalitis (GAE) caused by Acanthamoeba and Balamuthia species.

Observation:

  • Three new cases from Venezuela are presented: two fatal GAE cases caused by Balamuthia mandrillaris in immunocompetent individuals, and one fatal PAM case caused by Naegleria fowleri in a previously healthy individual after water immersion.
  • The GAE cases highlight that Balamuthia mandrillaris infections can occur in immunocompetent hosts, challenging the notion of opportunistic infection.

Findings:

  • Balamuthia mandrillaris caused GAE in two patients, one of whom was immunocompetent, demonstrating the pathogen's potential beyond opportunistic infections.
  • Naegleria fowleri caused PAM in a young, previously healthy individual, emphasizing the rapid and fatal progression of this form of amebic encephalitis.

Implications:

  • Neurological infections by amphizoic amebas may be underdiagnosed due to lack of awareness or low autopsy rates.
  • Increased recognition of these rare but devastating infections is crucial for timely diagnosis and potential intervention.

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