Effect of povidone iodine, chlorhexidine digluconate and toyocamycin on amphizoic amoebic strains, infectious agents of Acanthamoeba keratitis - a growing threat to human health worldwide.

INTRODUCTION: Free-living amoebae, ubiquitous in outer environments, in predisposing circumstances may exist as parasites, infectious agents of Acanthamoeba keratitis. In recent decades, the vision-threatening corneal infection is a growing human health threat worldwide, including Poland. The applied therapy is often ineffective due to diagnostic mistakes, various pathogenicity of Acanthamoeba strains and high resistance of cysts to drugs; many agents with possible anti-amoebic activity are still being tested. In the presented study, selected chemicals are investigated in terms of their in vitro effect on corneal and environmental Acanthamoeba strains. MATERIAL AND METHODS: Samples of a corneal isolate from a patient with severe Acanthamoeba keratitis,of assessed on the basis of genotype associations of 18S rRNA and the type strain, Acanthamoeba castellanii Neff cultivated in bacteria-free condition, were exposed to povidone iodine, chlorhexidine digluconate or toyocamycin. In vitro population dynamics of the strains were monitored and compared to those of control cultures. RESULTS: All chemicals showed anti-amoebic effects with different degrees of effectiveness. Significant differences were observed in the in vitro population dynamics, and the morpho-physiological status of A. castellanii Neff T4 and corneal strains determined as A. polyphaga T4 genotype, exposed to povidone iodine or toyocamycin, in comparison with chlorhexidine taken as reference. CONCLUSIONS: Time-dependent amoebstatic in vitro effects were demonstrated for all agents, in particular, the results of assays with povidone iodine are promising. No significant stimulation of encystation appeared; however, as cysticidal efficacy of chemicals is expected, complementary research is needed on different Acanthamoeba strains with modified agent concentrations and method application.

[Complex diagnosis of the early macular changes due to AMD]. / Kompleksowa diagnostyka wczesnych zmian w plamce w przebiegu zwyrodnienia plamki zwiazanego z wiekiem.

We demonstrated diagnostic cases of the early macular changes due to AMD, which caused central visual field disturbances. The aim of the study was to systemize the management in patients with macular lesions due to the age related macular degeneration, frequency determination and statement of the performed additional tests range. Patients reported central visual field distortions. We performed visual acuity testing, stereoscopic eye fundus examination, and PHP (macular visual field testing), which objectified distortions symptoms. Based on that tests and fellow eye condition, decision about OCT and FA and ICG performance were made. Further management was determined according to the results of that examinations: follow-up with vitamins and microelements supplementation or PDT. Our analysis confirm, that to monitor early macular changes due to AMD, follow-up examinations in 2-3 months interval are indicated: visual acuity testing, stereoscopic eye fundus examination and macular lesions modeling in PHP In difficult cases or in more advanced lesions FA, OCT and ICG were performed.