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Discovery of New Intracellular Pathogens by Amoebal Coculture and Amoebal Enrichment Approaches
09:04

Discovery of New Intracellular Pathogens by Amoebal Coculture and Amoebal Enrichment Approaches

Published on: October 28, 2013

Amebic meningoencephalitis in a patient with AIDS caused by a newly recognized opportunistic pathogen. Leptomyxid

A P Anzil1, C Rao, M A Wrzolek

  • 1Department of Pathology, Kings County Hospital Center, NY.

Archives of Pathology & Laboratory Medicine
|January 1, 1991
PubMed

Insights

A leptomyxid ameba caused fatal meningoencephalitis in an individual with acquired immunodeficiency syndrome (AIDS). This opportunistic pathogen, previously unrecognized in humans, highlights the need for accurate ameba identification.

Area of Science:

  • Medical Mycology
  • Infectious Diseases
  • Neurology

Background:

  • A fatal case of meningoencephalitis is presented in a patient with acquired immunodeficiency syndrome (AIDS).
  • The causative organism, a leptomyxid ameba, is an opportunistic pathogen not previously recognized in humans.
  • The patient was a 36-year-old male intravenous drug abuser with an 18-day hospital course.

Observation:

  • A fatal case of meningoencephalitis occurred in a 36-year-old male intravenous drug abuser with AIDS.
  • Clinical presentation included fever, headache, nuchal rigidity, and hemiparesis.
  • Cerebral computed tomography revealed multiple hypodense lesions.

Findings:

  • Neuropathologic examination identified multifocal meningoencephalitis with amebic trophozoites and cysts.
  • The amebic morphology was indistinguishable from Acanthamoeba.
  • Immunofluorescence revealed antigenic identity with a free-living leptomyxid ameba, distinct from Acanthamoeba.

Implications:

  • This case highlights leptomyxid amebas as a novel opportunistic human pathogen.
  • Accurate species identification using immunofluorescence is crucial for morphologically similar amebas.
  • Understanding amebic infections in immunocompromised hosts is critical for diagnosis and treatment.

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