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Free-living amoebic encephalitis - Case series
Sithara Nasar Thottathil Puthanpurayil1, Aiswarya Mukundan1, Suryakala Ravi Nair1
1Department of Microbiology, Government Medical College, Thrissur, Kerala, India.
Tropical Parasitology
|October 16, 2024
Summary
Free-living amoeba infections, including Naegleria fowleri and Acanthamoeba, rapidly caused fatal central nervous system disease in two patients. Early diagnosis via microscopy and PCR was crucial but treatment options remain limited.
Area of Science:
- Neurology
- Infectious Diseases
- Parasitology
Background:
- Free-living amoebae (FLAs) like Naegleria fowleri, Acanthamoeba, and Balamuthia are ubiquitous in freshwater and soil.
- While generally not pathogenic, these amoebae can cause severe, life-threatening central nervous system (CNS) infections in humans.
Purpose of the Study:
- To report two cases of fulminant CNS infections caused by free-living amoebae.
- To highlight the diagnostic challenges and rapid progression of these rare infections.
Main Methods:
- Case report detailing clinical presentation, diagnostic procedures, and outcomes.
- Cerebrospinal fluid (CSF) analysis including direct microscopy and molecular methods (polymerase chain reaction [PCR]).
Main Results:
- Two patients presented with rapid-onset CNS symptoms mimicking pyogenic meningitis.
- Microscopy revealed amoebic trophozoites in CSF, confirmed by PCR for Naegleria fowleri and Acanthamoeba spp.
- Both patients unfortunately succumbed to their infections despite medical intervention.
Conclusions:
- CNS infections by free-living amoebae are rapidly progressive and highly fatal.
- Clinical suspicion is key, especially when CSF shows atypical findings (turbid, no bacteria, high protein, low sugar).
- Early diagnosis through direct microscopy and molecular techniques is vital for potential management, though treatment options are limited.
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