Primary Amoebic Meningoencephalitis Caused by Naegleria

Two new cases of primary amoebic meningoencephalitis and two previously reported cases are presented as the basis for a description of the clinical, pathological, epidemiological, and protozoological aspects of this infection. The patients acquired their illnesses from swimming in fresh water; the infections were culturally proved to be caused by free-living amoeboflagellates of the genus Naegleria. The infections were rapidly fatal, but in two cases the responsible pathogens were markedly inhibited in vivo (as well as in vitro) by amphotericin B; at present this drug appears to be the only promising treatment available for an otherwise fatal disease.