Scanning electron microscopic study of trophozoite and cyst stages of Naegleria fowleri.

Whole trophozoites and cysts of axenically cultivated naegleria fowleri were prepared for study of their surface morphology by scanning electron microscopy (sem). trophozoites and cyst stages were studied from chang's culture media. some trophozoites were examined after animal inoculation and brain isolation to compare the changes in surface features. photomicrographs of freeze-dried and critical point-dried organisms fixed with glutaraldehyde were presented along with views of both isolates of trophozoites to compare the surface features. sem revealed the surface of trophozoites to be undulating,wrinkled and covered at irregular intervals by protruding vesicles. there were also surface extensions which were long and thin in brain isolates which may help in the contact and cytolysis of host cells at some distance from the trophozoite. some cysts appeared wrinkled while others smooth,and empty cysts were also seen with many pores on the surface.