Evaluate adhesion of Acanthamoeba polyphaga trophozoites to scleral contact lenses

Abstract

The increase of contact lenses (CL) users resulted in significant increased number cases of Acanthamoeba keratitis (AK). The AK is a serious eye infection that can impair vision irreversibly. The etiological agent of this keratitis is the protozoan Acanthamoeba spp., which includes a total of 25 species and 20 distinct genotypes, but only 10 have actually been identified as causing AK. The mechanism of amoeba adhesion to the CL is associated with keratitis pathogenesis, and it is influenced by a number of factors, for example, the CL material and inappropriate use and care of these lenses. It has been proven that Acanthamoeba has the ability to adhere in conventional hydrogel lenses, silicone hydrogel, rigid gas-permeable and cosmetic lenses. Currently, there are scleral lenses on the market used by patients with keratoconus to control high or irregular astigmatism. To date, it is not known for sure the problems that the use of scleral lenses can trigger, however, cases of AK have been already detected in the use of them. In this way, this study aims to verify if Acanthamoeba polyphaga is able to adhere to scleral CL that received a superficial treatment with Plasma O2 or Plasma O2 + Hydra-PEG, which aims to decrease the adhesion of microorganisms, since this mechanism has not yet been explored in the world literature. (AU)