Primary Amoebic Meningoencephalitis with Progression to Brain Death Following Naegleria Fowleri Infection in a Teenage Female

Naegleria fowleri is a high-temperature freshwater-living amoeba that causes primary amoebic meningoencephalitis (PAM) by invading nasal epithelium. N. fowleri lives ubiquitously in high-temperature freshwater, but only around 400 cases of PAM have been published worldwide. The mortality rate is 98%. No treatment is 100% effective. A previously healthy 17-year-old female presented to an urgent care center with fever, headache, sore throat, ear pain, and dizziness. She had swum in freshwater 5 days prior. Her symptoms progressed to altered mental status, photo- and phonophobia, and neck stiffness. Within 4 days, she developed increased intracranial pressure (ICP) and eventually brain death. Two unsuccessful lumbar punctures were attempted before the third provided cerebrospinal fluid (CSF) for polymerase chain reaction (PCR) analysis. Magnetic resonance imaging showed diffuse cerebral edema, effacement of basal cisterns, tonsillar herniation with diffuse loss of gray-white matter differentiation, leptomeningitis, bifrontal encephalitis with evolving frontal lobe cortical infarcts, and ventriculitis. She was treated with metronidazole, vancomycin, ceftriaxone, acyclovir, and doxycycline. Her increased ICP progressed to brain death, and she died 11 days after lake exposure. CSF PCR was reported positive for N. fowleri the day after her death. Despite advances in diagnostic testing for N. fowleri with PCR, mortality rate is high and current treatments are highly ineffective. This case highlights the importance of epidemiological exposure and considering PAM on the differential diagnosis. Although headache and fever are benign symptoms, they could also represent the first stages of a deadly disease and their progression should be addressed promptly.