Review of the diagnosis, pathophysiology, and treatment of Naegleria fowleri-induced Primary Amoebic Meningoencephalitis

Naegleria fowleri is a thermophilic, ubiquitous, free-living amoeba, but is also known as the “brain-eating” amoeba. This is the etiological agent of a rare and fulminant waterborne disease known as Primary Amoebic Meningoencephalitis (PAM) that is acutely fatal in 90-99% of reported cases. Those who come into contact with infested waters are at risk of introducing the amoeba into their upper nasal canal, whence the trophozoite form is known to migrate along the olfactory nerve, through the cribriform plate, and enter the central nervous system. Although the exact pathogenesis of N. fowleri is not known, studies have demonstrated contact-dependent and contact-independent mechanisms that contribute to the pathogen’s invasion of and damage to the host central nervous system. This review includes the diagnosis, pathophysiology, main therapeutic strategies, and preventative strategies against N. fowleri-induced PAM.