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Acute granulomatous acanthamoeba encephalitis in an immunocompetent patient

Peter Lackner1, Ronny Beer, Gregor Broessner

  • 1Department of Neurology, Innsbruck Medical University, 6020 Innsbruck, Anichstrasse 35, Austria, Europe. peter.lackner@i-med.ac.at

Neurocritical Care
|October 23, 2009
PubMed
Abstract

Insights

Acanthamoeba lenticulata T5 caused fatal granulomatous Acanthamoeba encephalitis (GAE) in an immunocompetent teen. Successful treatment involved high-dose antibiotics, including meropenem, linezolid, moxifloxacin, and fluconazole.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Microbiology

Background:

  • Acanthamoeba species are known pathogens causing fatal granulomatous Acanthamoeba encephalitis (GAE), primarily in immunocompromised individuals.
  • This report details a rare case of GAE in an immunocompetent host.

Observation:

  • A 17-year-old immunocompetent patient presented with acute purulent meningoencephalitis.
  • Despite initial antimicrobial therapy, the patient experienced relapses, indicating a persistent or resistant infection.
  • Cerebrospinal fluid analysis revealed Acanthamoeba lenticulata T5 as the causative agent, entering the central nervous system via ethmoidal bone dehiscence.

Findings:

  • The patient developed severe vasospasm, leading to multiple strokes and significant neurological deficits.
  • Successful treatment was achieved with a combination of high-dose meropenem, linezolid, moxifloxacin, and fluconazole.
  • A partially adapted antimicrobial regimen was continued post-initial treatment.

Implications:

  • This case highlights the potential for Acanthamoeba lenticulata to cause severe CNS infections even in immunocompetent individuals.
  • The successful treatment strategy offers a potential therapeutic approach for GAE in non-immunocompromised patients.
  • Early identification and aggressive combination antimicrobial therapy are crucial for managing GAE and preventing neurological sequelae.

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