Bacterial colonization of rigid gas permeable and hydrogel contact lenses by Staphylococcus aureus

Abstract

Staphylococcus aureus ATCC 6538 and a clinical isolate of S. aureus from a bacterial keratitis patient were examined for their ability to adhere to etafilcon A, polymacon, silafocon, and pauflufocon A, B and C contact lenses. Both isolates adhered more to the rigid gas permeable (RGP) materials than to the hydrogel lenses tested (P < 0.05). S. aureus ATCC 6538 adhered to the etafilcon A material to a greater extent than did the clinical isolate (P < 0.05). There were no statistically significant differences in the recovery of staphylococci from unworn lens materials when surface area, composition and ionicity were evaluated for either the hydrogel or RGP lenses tested against lenses of a similar type. However, differences were observed when hydrogel lenses were evaluated against RGP lenses (P < 0.05). These differences may be related to water content.