Biofilms and contact lenses: problems and solutions

Abstract

Contact lenses provide excellent vision correction for many people worldwide. However, they can become colonised by microorganisms and this can result in infections and inflammatory responses at the surface of the eye during wear. If not quickly and appropriately treated, the infections can lead to loss of vision and even loss of the eye. The microorganisms, most commonly bacteria, that colonise the lenses can form biofilms on the lenses. For the past 25 years, we have been studying the epidemiology of contact lens-related infection and inflammation, the causative organisms, risk factors for developing the conditions, and new ways of reducing biofilm formation. This article provides an overview of this research.

The Role of Biofilms in Contact Lens Associated Fungal Keratitis

“…Such multicellular structures embedded within intercellular EPS were also observed when dimorphic fungi such as C. albicans or filamentous fungi such as Fusarium spp. were cultured on soft CLs in broth media for 48 h [25,46], C. albicans on human cadaveric cornea or A. fumigatus on primary cultures of human Limbo-Corneal fibroblasts for 24 h [47,48].…”

“…Optimizing the concentrations of these agents in the CL solutions for better anti-fungal-biofilm activities, either as a single antiseptic or combinational preservatives, will possibly see a reduced incidence rate of CLAFK. Novel anti-biofilm agents have also been introduced into the CL care systems to prevent CLAFK, such as enzymes or chemicals that can break down the EPS matrix of fungal biofilms, or novel inhibitors of quorum sensing systems that regulate fungal biofilm formation [47,88,89]. Although these novel agents demonstrated excellent anti-fungal-biofilm activities in vitro, they are still in early experimental stages and clinical success is yet to be reported [47].…”

“…Novel anti-biofilm agents have also been introduced into the CL care systems to prevent CLAFK, such as enzymes or chemicals that can break down the EPS matrix of fungal biofilms, or novel inhibitors of quorum sensing systems that regulate fungal biofilm formation [47,88,89]. Although these novel agents demonstrated excellent anti-fungal-biofilm activities in vitro, they are still in early experimental stages and clinical success is yet to be reported [47].…”

A Comprehensive Review of Microbial Biofilms on Contact Lenses: Challenges and Solutions

“…P. aeruginosa is the most prevalent and it is isolated from at least 70% of cases globally. 24 Although they are less common than bacteria, fungi like Candida albicans and Fusarium species are nevertheless often involved in the etiology of keratitis. In addition, the protozoan Acanthamoeba causes a rare but severe form of infectious keratitis.…”

“… 22 Biofilms of both the CL cases and the CL of persons with MK contain these pathogens. 24 Despite being a rare side effect of wearing CLs, MK is one of the leading causes of blindness in both underdeveloped and developed nations. 22 …”