Effectiveness of AOSept Plus and Biotrue® Contact Lens Disinfecting Solutions against Clinical Isolates of Acanthamoeba spp.

Introduction: The usage of contact lens among the community is increasing due to trend and as an alternative of wearing glasses. However, most ocular diseases and eye infections such as Acanthamoeba keratitis are more related to contact lens usage. The contact lens disinfecting solutions (CLDS) are supposed to be able to eradicate the microorganisms that could possibly cause eye infections. Objective: This study was conducted to determine the effectiveness of the contact lens disinfecting solutions against Acanthamoeba spp. cysts of clinical isolates based on manufacturer's recommended soaking time and variable soaking times. Materials and Methods: CLDS were tested against two isolates of Acanthamoeba spp. in durations recommended by the product manufacturer; 4 and 6 hours and also in extended duration of 8 hours soaking. The disinfecting solutions tested were AOSept Plus and Biotrue® multipurpose solution against two clinical isolates (HKL 55 & HS 19). The Acanthamoeba spp. isolates were subcultured onto non-nutrient agar and the cysts produced were mixed with disinfectants separately according to different soaking hours. After the soaking duration, the cysts were cultured onto non-nutrient agar layered with heat-killed E. coli and incubated at 30°C. The cultures were observed under inverted microscope for 14 days continuously to see any excystment of the cyst. The failure of the cysts to excyst indicates the efficiency of the disinfectants to kill the cyst successfully. Results: AOSept Plus exhibited good anti-Acanthamoeba activity and was able to inhibit the excystment of Acanthamoeba spp. cysts in all isolates. Biotrue® Multipurpose solution failed to exhibit anti-Acanthamoeba activity. Conclusion: AOSept Plus representing the hydrogen peroxide based contact lens disinfecting solution is a choice for contact lens wearers if Acanthamoeba keratitis is to be prevented. [ABSTRACT FROM AUTHOR]