A STUDY ON THE ACTIVITY OF ANTISEPTICS AND ANTIBIOTIC ON 2 ISOLATES OF ACANTHAMOEBA FROM CORNEAL ULCERATIONS

Purpose To study the in vitro amoebicidal activity of antiseptics and antibiotics. Methods Antiseptics (hexamidine, chlorhexidine, picloxydi ne, PHMB, polyvidone iodine) and an antibiotic (colimycine) were teste d on two Acanthamoeba isolates from corneal ulcers under soft contact lenses. The appearence of trophozoi'ts and the increase of the number of cysts show their viability. Results Four antiseptics and colimycin proved to be active in vitro on the two Acanthamoeba isolates: hexamid in 0,1 % after 3 to 6 hours incubation, picloxydin 0,05 % after I to 3 hours incubation (Wilcoxon test, p<0,05), chlorhexidin 0,02 % after 3 hours (Wilcoxon test, p<0,01), PHBM 0,02 % after 3 hours (Wilcoxon te st, p<0,01) and colimycin 125 000 Ul/ml after I to 3 hours incubation. polyvidone iodine proved ineffective. Conclusion Our results confirm that hexamidin, chlorhexidin and PHMB have an amoebicidal activity on the two stains, and show that colimycine, which hbs already been teste d has also an amoebicidal activity; picloxydine is effective after I t o 3 hours; there is a considerable variability which exists between th e isolates and the sensitivity of the isolates is time-dependent Medic al polytherapy is therefore necessary especially if the sensitivity of the Acanthamoeba has not been tested.