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Brain Eater Amoeba: A Case Report
1Assistant Professor, Department of General Medicine, Government Medical College, Thrissur, Kerala, India.
Background:
A free-living amoeba, Naegleria fowleri, can live in both warm fresh water and soil. It causes the deadly central nervous system (CNS) infection known as primary amebic meningoencephalitis (PAM).
Case Description:
A 36-year-old male with no comorbidities presented with headache and high-grade fever for 3 days and was admitted with an episode of generalized tonic-clonic seizures (GTCS). He had a nasal bone fracture at the age of 15 years. No history of bathing in lake or pond water. On examination, the patient was febrile with a stiff neck. Initially treated as acute pyogenic meningoencephalitis, as initial cerebrospinal fluid (CSF) and blood pictures were suggestive of the same. CSF Gram stain was negative, but CSF wet mount yielded a motile trophozoite resembling N. fowleri, later confirmed with polymerase chain reaction (PCR) and Sanger sequencing. His wife revealed he was using tap water for "ritual nasal rinsing" as a part of religious practices.
Final Diagnosis:
PAM. He expired due to recurrent episodes of ventricular tachycardia (VT). Epidemiological link was confirmed by analysis of tap water, which also showed N. fowleri. Discussion: When making a differential diagnosis for any suspected case of pyogenic meningoencephalitis, preventable yet fatal PAM should be taken into account. Asking about freshwater exposure, including the history of nasal rinsing, and considering a simple CSF wet mount examination in all "Gram stain negative CSF samples" guides in early diagnosis.
Insights
Primary amebic meningoencephalitis (PAM), a deadly brain infection caused by Naegleria fowleri, can result from nasal rinsing with contaminated tap water. Early diagnosis via CSF wet mount is crucial for suspected cases.
Area of Science:
- Infectious Diseases
- Neurology
- Microbiology
Background:
- Naegleria fowleri is a free-living amoeba found in warm freshwater and soil.
- It causes primary amebic meningoencephalitis (PAM), a fatal central nervous system infection.
Purpose of the Study:
- To highlight a rare case of PAM caused by nasal rinsing with tap water.
- To emphasize the importance of considering PAM in differential diagnoses for meningoencephalitis.
Main Methods:
- A case study of a 36-year-old male presenting with symptoms suggestive of meningoencephalitis.
- Cerebrospinal fluid (CSF) analysis, including wet mount microscopy, PCR, and Sanger sequencing.
- Epidemiological investigation linking tap water to the infection.
Main Results:
- CSF wet mount revealed motile trophozoites consistent with Naegleria fowleri.
- PCR and Sanger sequencing confirmed the presence of Naegleria fowleri.
- Tap water used for nasal rinsing was identified as the source of infection.
Conclusions:
- Preventable yet fatal PAM should be considered in suspected pyogenic meningoencephalitis cases.
- Nasal rinsing with tap water is a potential route of infection.
- Early diagnosis is aided by CSF wet mount examination in Gram stain-negative samples.
