Article

Factors influencing bacterial adhesion to contact lenses.

Brien Holden Vision Institute, Sydney, NSW, Australia.
Molecular vision (impact factor: 2.2). 01/2012; 18:14-21. pp.14-21
Source: PubMed

ABSTRACT The process of any contact lens related keratitis generally starts with the adhesion of opportunistic pathogens to contact lens surface. This article focuses on identifying the factors which have been reported to affect bacterial adhesion to contact lenses. Adhesion to lenses differs between various genera/species/strains of bacteria. Pseudomonas aeruginosa, which is the predominant causative organism, adheres in the highest numbers to both hydrogel and silicone hydrogel lenses in vitro. The adhesion of this strain reaches maximum numbers within 1h in most in vitro studies and a biofilm has generally formed within 24 h of cells adhering to the lens surface. Physical and chemical properties of contact lens material affect bacterial adhesion. The water content of hydroxyethylmethacrylate (HEMA)-based lenses and their iconicity affect the ability of bacteria to adhere. The higher hydrophobicity of silicone hydrogel lenses compared to HEMA-based lenses has been implicated in the higher numbers of bacteria that can adhere to their surfaces. Lens wear has different effects on bacterial adhesion, partly due to differences between wearers, responses of bacterial strains and the ability of certain tear film proteins when bound to a lens surface to kill certain types of bacteria.

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Keywords

bacterial adhesion
 
bacterial strains
 
certain tear film proteins
 
certain types
 
chemical properties
 
contact lens
 
contact lens material
 
contact lens surface
 
contact lenses
 
HEMA)-based lenses
 
HEMA-based lenses
 
highest numbers
 
lenses
 
maximum numbers
 
opportunistic pathogens
 
predominant causative organism
 
silicone hydrogel lenses
 
various genera/species/strains
 
vitro studies
 
water content