각막기질세포에 대한 아칸트아메바각막염 치료제의 영향

Effect of Amoebicidal Agents on the Human Corneal Keratocytes in Vitro

Purpose: To evaluate the effect of polyhexamethylene biguanide (PHMB) and chlorhexidine on Acanthamoeba cysts and cultured human keratocytes. Methods: Each well of two-fold diluted PHMB and chlorhexidine were treated on the Acanthamoeba cyst suspension of 5×104 cysts/ml for 8, 24, and 48 hours to measure the minimal cysticidal concentration (MCC) of each disinfectant and was exposed to the human corneal keratocytes of 5×104 cells/ml for same hours to measure the survival rate of keratocytes. Inverted phase-contrast micrograph and electron microscopy for observing the morphologic changes were evaluated. Results: MCC of PHMB was 9.42 ?g/ml, 5.62 ?g/ml, and 2.37 ?g/ml, and chlorhexidine was 24.32 ?g/ml, 10.02 ?g/ml, and 7.02 ?g/ml respecitvely in 8, 24, and 48 hours. The survival rate of keratocytes at MCC was 91.7%, 64.6%, and 49.7% in PHMB of which significant decreases were found at 24 and 48 hours, and 95.7%, 90.6%, and 78.1% in chlorhexidine of which significant decrease was only found at 48 hours. The higher the concentration of disinfectants, cysts and keratocytes demonstrated more damaged appearance. Conclusions: The amoebicidal efficacy of PHMB and chlorhexidine was similar. However, in consideration of toxic effect on keratocytes by disinfectants, chlorhexidine is suggested to be more clinically useful than PHMB.