Survivability of Acanthamoeba Strains Isolated from Clinical and Environmental Specimens During Axenization

Abstract

Acanthamoeba is a free living protozoa that can cause keratitis and granulomatous amoebic encephalitis. Physiological
characteristics of this amoeba are found to have a medical importance in which it can be related to the pathogenicity
potential of the organism. This study was carried out to investigate the physiological characteristics of survivability
during axenization. Six Acanthamoeba strains from three clinical isolates (HSB 1, HKL 48 and HKL 95) and three
environmental isolates (PHS 2, PHS 11 and PHS 15) were used in this study. Axenization test was done by treating cysts
with hydrochloric acid (3%) and Page saline containing Gentamicin (100 ìg/ml). Cysts were then cultured into PYG
enrich media, incubated at 30oC and the presence and proliferation of trophozoites of Acanthamoeba were observed.
This study showed that PHS 15, HSB 1, HKL 48 and HKL 95 could be axenized but they have poor proliferation rate in PYG
enrich media. The result showed that the difference between both clinical and environmental isolates was observed in
two strains; PHS 2 and PHS 11. This indicates that there is a possibility that the physiological traits of strains from both
isolates are the same and strains from the environment are able to show the pathogenic potential and capable of
causing infection to human.