Pathogenesis of contact lens induced bacterial corneal ulcers—a review and an hypothesis

Abstract

Previous research into the aetiology of contact lens‐related infection has focussed upon a) the ability of bacteria such as P. aeruginosa to adhere to contact lenses, b) the role of lens contamination, and c) patient compliance factors. However, these studies have not fully explained the increased susceptibility to P. aeruginosa infection during lens wear. It is argued that bacterial adherence to the corneal epithelium is a prerequisite for the development of corneal infection. We explore the possibility of an aetiological role in contact lens related infection for fibronectin, a glycoprotein that is associated with some cell surfaces and body fluids, by drawing upon published mechanisms of bacterial adherence to human buccal mucosa in cystic fibrosis. An hypothesis is presented that contact lenses deplete fibronectin in the tears and/or corneal epithelium, allowing bacteria to adhere to the epithelium, resulting in corneal infection.

Key words:

• Cornea
• contact lens
• corneal infection
• bacterial adherence
• Pseudomonas aeruginosa
• fibronectin
• sialic acid
• cystic fibrosis