Now that summer is here, and our lakes, rivers, springs, and other freshwater bodies are once again popular for all types of bathing activities, the possibility of Primary Amebic Meningoencephalitis (PAM) due to infection with the ubiquitous freshwater ameba Naegleria fowleri increases.
The Department of Health in Orange County (DOHOrange) advises clinicians and laboratorians to be on alert for cases of Primary Amebic Meningoencephalitis (PAM) caused by the ameba Naegleria fowleri.
Because the infection is uncommon, even during the summertime, there is often a low index of suspicion, as early symptoms are non-specific, and quite often mimic bacterial or viral meningitis.
The infection occurs when ameba-contaminated freshwater contacts nasal mucosa. The ameba can penetrate nasal mucosa, travel along the olfactory nerves, and cross the cribiform plate, entering the brain.
The median time from onset of symptoms to death is 5 days. The fatality rate of this fulminating infection is over 97%. Despite these facts, successful case outcomes are possible.
These most recent successful outcomes ( Central Florida: https://vimeo.com/182034993, Arkansas: Linam, et al: Successful Treatment of an Adolescent With Naegleria fowleri Primary Amebic Meningoencephalitis : http://pediatrics.aappublications.org/content/135/3/e744.long ) started with early suspicion and awareness; both at the point of care, and in the laboratory.
The patient's history over the past 14 days is critical: nasal freshwater exposure??
Time is of the essence in treatment initiation.
- Headache (usually severe, sudden-onset), fever, nausea/vomiting.
- Photophobia may also be present.