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In Vivo Imaging Systems (IVIS) Detection of a Neuro-Invasive Encephalitic Virus
Published on: December 2, 2012
[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.
Introduction:
Infection of the Central Nervous System by free living amebas is an unusual event, 344 cases have been reported to date. The disease becomes evident in two different clinical fashions: Primary Amebic Meningoencephalitis (PAM) caused by Naegleria fowleri and Granulomatous Amebic Encephalitis (GAE) induced by Spp. of Acanthamoeba and Balamuthia.
Clinical Cases:
The authors report three new cases from Venezuela. Case 1. 34 years old man, with a chief complaint of general malaise, headache and fever, a diagnosis of common cold was made and the patient was treated as such, he did not improve and was admitted to the hospital with deterioration of his clinical status; the patient died 10 days after the onset of his illness which was determined to be GAE produced by Balamuthia mandrillaris. Case 2. 8 years old female admitted to the hospital because of fever, headache and generalized seizures of sudden onset; neurocysticercosis was diagnosed and following improvement the patient was discharged and readmitted on two occasions because of relapse and worsening of her illness, she died 2 months after the onset of her disease that was diagnosed by autopsy as GAE due to Balamuthia mandrillaris. Case 3. 16 years old male, previously healthy, who following immersion in a water tank was admitted to the hospital because of meningeal irritation that progressed to coma and death in a 7 day lapse; autopsy revealed PAM by Naegleria fowleri. The two cases of GAE due to Balamuthia mandrillaris occurred in apparently immunocompetent individuals, contrary to the statement that these microorganisms are opportunistic.
Conclusion:
We believe that neurological infection by amphizoic amebas is being underdiagnosed, probably due to ignorance regarding this pathology or because of a very low autopsy rate in most countries.
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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