Contact Lens-related Keratitis Research Articles

The most common contact lens-related complications: A brief review of the literature

Introducion and purpose Millions of people use contact lenses every day. Their primary and most common use is correcting refractive errors. Despite their beneficial purpose, contact lens use has many complications. It is estimated that 5 to 50% of patients may develop at least a single complication. The state of knowledge Contact lens-related complications are multifactorial. One of the main reasons for contact lens discontinuation is contact lens discomfort. Patients most often report dryness, burning, and irritated eyes. Other disorders can be briefly divided into conjunctival and corneal complications. The most common conjunctival and allergic complication of contact lens use is giant papillary conjunctivitis. Other significant conditions involving the conjunctiva can also be superior limbic keratoconjunctivitis or allergic or toxic conjunctivitis. Corneal complications, on the other hand, seemed to be much more severe. These include superficial punctate keratitis, peripheral corneal ulceration, and contact lens-related keratitis. Also, abrasion can occur due to improper eye hygiene or mechanical damage during lens replacement. It should also be remembered that prolonged use of lenses can lead to hypoxia and corneal edema. Summary This paper briefly outlines the possible complications of contact lens use. It is important to remember that despite their appropriate use, sometimes significant complications can occur. Noteworthy, corneal, or conjunctival complications require discontinuation of the lenses and appropriate treatment.

Comparative Analysis of Contact Lens-related Bacterial Keratitis According to Culture Positivity: A 25-year Retrospective Study

Purpose: This study investigated the microbiological profile and clinical characteristics of culture positive (CP) contact lens-related bacterial keratitis (CLBK) and compared them to culture negative (CN) cases.Methods: We retrospectively analyzed 142 CLBK patients hospitalized between January 1998 and December 2022. The CP and CN groups consisted of 79 eyes (100 isolates) and 63 eyes, respectively. We investigated the microbiological profile in the CP group and compared the epidemiology, predisposing factors, clinical characteristics, and treatment outcomes between the CP and CN groups. Poor treatment outcomes were defined as a final best-corrected visual acuity (BCVA) ≤ 0.5, worsened BCVA after treatment, or the need for surgical intervention. We evaluated the risk factors for poor treatment outcomes in the entire cohort through two-proportional Z-test analysis.Results: In CP group, gram-negative bacteria accounted for 85%, and common isolates were <i>Pseudomonas</i> (27%) and <i>Serratia</i> (26%) species. There were significant differences in mean age (27.0 years vs. 33.8 years, <i>p</i> = 0.009) and a history of therapeutic bandage contact lens wear (13.9% vs. 28.6%, <i>p</i> = 0.031) between the CP and CN groups. However, there were no significant differences in symptom duration, prior use of topical antibiotics, sleeping with wearing CL, epithelial defect size, hypopyon, and poor treatment outcomes. Significant risk factors for poor treatment outcomes in the entire group included deep infiltration (Z = 2.88), epithelial healing time ≥ 7 days (Z = 2.30), initial BCVA < 0.1 (Z = 2.20), over date use of contact lens (Z = 2.10), and epithelial defect size ≥ 5 mm<sup>2</sup> (Z = 2.05).Conclusions: There were no significant differences in clinical characteristics and treatment outcomes between the CP and CN groups. Poor initial clinical findings and over date use of contact lens were associated with poor treatment outcomes in both groups.

Multi-Target Effect of Aloeresin-A against Bacterial and Host Inflammatory Targets Benefits Contact Lens-Related Keratitis: A Multi-Omics and Quantum Chemical Investigation.

Contact lens-mediated microbial keratitis caused by Pseudomonas aeruginosa and Streptococcus pneumoniae provokes corneal damage and vision loss. Recently, natural phytochemicals have become complementary medicines for corneal destruction. Herein, we aimed to identify multi-targeting Aloe vera-derived phytochemicals capable of inhibiting bacterial and host targets of keratitis through ADME (absorption, distribution, metabolism, and excretion), docking, molecular dynamics (MD) simulation, MMGBSA (molecular mechanics generalized Born surface area) and density functional theory (DFT) investigations. An extensive literature search revealed ExoU, ExoS, ExoT, ExoY, and PLY as virulent bacterial targets. Simultaneously, differential gene expression (DGE) and pathway enrichment analysis-specified host transcription factor (SPI1) influences keratitis pathogenesis. Molecular docking analysis uncovered aloeresin-A as a promising inhibitor against bacterial and host targets, demonstrating strong binding energies ranging from -7.59 to -6.20 kcal/mol. Further, MMGBSA and MD simulation analysis reflect higher binding free energies and stable interactions of aloeresin-A with the targets. In addition, DFT studies reveal the chemical reactiveness of aloeresin-A through quantum chemical calculations. Hence, our findings show aloeresin-A to be a promising candidate for effectively inhibiting keratitis. However, additional research is imperative for potential integration into lens care solutions.

Clinical comparative analysis of bacterial keratitis according to contact lens use: a retrospective study in a tertiary referral center of South Korea.

To compare the clinical aspects and treatment outcomes of contact lens-related bacterial keratitis (CLBK) and non-CLBK patients. Altogether 217 patients of bacterial keratitis (CLBK; 62, non-CLBK; 155) hospitalized between January 2012 and December 2020 were retrospectively analyzed for epidemiology, microbiological profiles, predisposing factors, clinical characteristics, and treatment outcomes. Poor treatment outcomes (PTO) were defined as a final BCVA < 0.3 (Snellen), a decreased visual acuity after treatment, complications, or surgical intervention. Relative importance of the initial clinical features leading to PTO was assessed using the random forest model and two-proportion Z-test. The most common predisposing factors were sleeping with wearing CL (51.6%) in the CLBK group and trauma (55.5%) in the non-CLBK group. There were significant differences between the two groups in mean age (35.1:55.1years, p < 0.001), female sex (56.5:34.8%, p = 0.003), symptom duration (6.2:6.9days, p = 0.019), gram-negative organisms (83.3:48.3%, p = 0.008), epithelial healing time (8.5:14.1days, p = 0.004), final BCVA (0.15:0.46 logMAR, p = 0.015), and PTO (9.7:21.9%, p = 0.035). For the entire group, the initial BCVA < 0.1 (27.9%), symptom duration ≥ 5days (19.4%), age ≥ 60years (16.4%), and hypopyon (14.0%) were important initial clinical features leading to PTO in the random forest model. In CLBK group, the type of CL or CL-related history was not significantly related to PTO. CLBK patients had a higher proportion of females, younger age, gram-negative bacteria, and better treatment outcomes than those of non-CLBK patients. There were no significant risk factors leading to PTO in either the type of CL or CL-related history.

Antimicrobial Efficacy of an Ultraviolet-C Device against Microorganisms Related to Contact Lens Adverse Events.

The purpose of the study was to assess the antimicrobial activity of an ultraviolet-C (UVC) device against microorganisms implicated in contact lens related adverse events. An UVC device with an emitting 4.5 mm diameter Light Emitting Diode (LED; 265 nm; 1.93 mJ/cm2) was used. Pseudomonas aeruginosa, Staphylococcus aureus, Fusarium solani, and Candida albicans agar plate lawns were exposed to the device beams for 15 and 30 s at 8 mm distance. Following the exposure, the diameter of the growth inhibition zone was recorded. Contact lenses made of Delfilicon-A, Senofilicon-A, Comfilicon-A, Balafilicon-A, Samfilicon-A and Omafilicon-A and a commercially available contact storage case was used. They were exposed to bacterial and fungal strains for 18 h at 37 °C and 25 °C respectively. After this, the samples were exposed to UVC for 30 s at 8 mm distance to determine the antimicrobial efficacy. Samples were then gently washed and plated on appropriate agar for enumeration of colonies. The UVC exposure reduced microbial growth by 100% in agar lawns, and significantly (p < 0.05) reduced microbial contamination to contact lenses and cases, ranging between 0.90 to 4.6 log. Very short UVC exposure has high antimicrobial efficacy against most of the predominant causative microorganisms implicated in contact lens related keratitis. UVC could be readily used as a broad-spectrum antimicrobial treatment for lens disinfection.

A rationally designed synthetic antimicrobial peptide against Pseudomonas-associated corneal keratitis: Structure-function correlation

Contact lens wearers are at an increased risk of developing Pseudomonas-associated corneal keratitis, which can lead to a host of serious ocular complications. Despite the use of topical antibiotics, ocular infections remain a major clinical problem, and a strategy to avoid Pseudomonas-associated microbial keratitis is urgently required. The hybrid peptide VR18 (VARGWGRKCPLFGKNKSR) was designed to have enhanced antimicrobial properties in the fight against Pseudomonas-induced microbial keratitis, including contact lens-related keratitis. In this paper, VR18's modes of action against Pseudomonas membranes were shown by live cell Raman spectroscopy, live cell NMR, live-cell fluorescence microscopy and measures taken using sparsely tethered bilayer lipid membrane bacterial models to be via a bacterial-specific membrane disruption mechanism. The high affinity and selectivity of the peptide were then demonstrated using in vivo, in vitro and ex vivo models of Pseudomonas infection. The extensive data presented in this work suggests that topical employment of the VR18 peptide would be a potent therapeutic agent for the prevention or remedy of Pseudomonas-associated microbial keratitis.

Epidemiology, Microbiology, and Genetics of Contact Lens-Related and Non-Contact Lens-Related Infectious Keratitis.

Infectious keratitis is a rare but severe condition associated with a range of ocular and systemic predisposing conditions, including ocular trauma, prior surgery, surface disease, and contact lens (CL) wear. This review explores the epidemiology of infectious keratitis, specifically the differences in disease incidence and risk factors, causative organism profile and virulence characteristics and host microbiome, genetics, gene expression, proteomics, and metabolomic characteristics in CL-related and non-CL-related diseases. Differences exist in the epidemiology, demographics, causative organisms, and their virulence characteristics in CL-related and non-CL-related diseases, and there is less evidence to support differences between these groups of individuals in the ocular surface microbiome, genetics, and pathways of disease. Genetic variations, however, in the host immune profile are implicated in both the onset and severity of infectious keratitis in CL and non-CL wearers. As technologies in metabolomics, proteomics, and genomics improved to be better able to process small-volume samples from the ocular surface, there will be improved understanding of the interplay between the CL, ocular surface, host immune profile, and the microbial environment. This may result in a more personalized approach in the management of disease to reduce disease severity.

Clinical factors associated with positive corneal culture in suspected microbial keratitis

AimsDetermine demographic and clinical characteristics associated with positive culture in suspected microbial keratitis. MethodsRetrospective audit of patients that had corneal scrapings between October 1999-September 2004 at Princess Alexandra Hospital. Clinical information was gathered from medical records, smear and culture results from the local microbiology database. Univariate and multivariate analyses of variables associated with positive cultures and calculation of population attributable risk percentage (PAR). ResultsUnivariate analysis showed that positive cultures were associated with patients over 60 years (81% vs 55%; p < 0.001), presenting visual acuity (VA) of 6/24 or worse (74% vs 57%; p = 0.012) or contact lens-related keratitis (CLK 77% vs 62%; p = 0.08). Analysis of patients’ clinical presentation showed that positive culture was associated with a central epithelial defect (74% vs 57%; p = 0.012), anterior chamber reaction of 2 + cells or worse (73% vs 56%; p = 0.03), an epithelial defect of 2 mm or more in diameter (71% vs 50%; p = 0.006) or no prior treatment with antibiotics (68% vs 56%; p = 0.053). Multivariate analysis showed the independent variables associated with positive cultures were VA of 6/24 or worse on presentation, contact lens-related keratitis, age greater than 60 years, an anterior chamber reaction of 2 + cells or worse and no prior treatment with antibiotics. The factor with the highest attributable risk (PAR%) for a positive corneal scraping was VA of 6/24 or worse on presentation (21%). ConclusionsIn this series positive cultures were associated with poor presenting VA contact lens keratitis (CLK), older age, anterior chamber reaction and no prior treatment with antibiotics.

Scedosporium apiospermum contact lens-related keratitis: a case report and literature review.

Scedosporium apiospermum (SA) is commonly present in temperate climates. It can induce cutaneous and subcutaneous tissue infections as well as disseminated infections in immunocompromised or immunocompetent hosts. The eye is rarely involved. Keratomycosis is usually caused by plant-related injuries. Here, we describe a patient with a severe and sight-threatening corneal abscess caused by SA, which was associated with contact lens wear and was successfully treated with a combination of surgical and medical therapies. An otherwise healthy 22-year-old woman, with history of contact lens wearing, was referred to the Ophthalmic Department of Bari University, Bari, Italy for evaluation of a corneal abscess and hypopyon in her left eye. Intensive topical and systemic antibiotic therapy was initiated after obtaining con- junctival swabs. Within 2 days, her ophthalmic condition had worsened, and her best-corrected visual acuity (BCVA) dropped to counting fingers. She underwent penetrating keratoplasty, after which her ophthalmic condition improved. Microbiological culture, obtained from the explanted cornea, revealed SA infection. This was addressed with specific topical and systemic therapy using voriconazole. Two weeks later, the con- dition of her left eye was stable, with mild corneal edema and no sign of acute graft rejection. Her BCVA improved to 20/25, and all medications were discontinued, except for the steroid eye drop. The patient was scheduled for a 1-month follow-up. Prompt identification of the etiological agent is mandatory to perform appropriate therapy in cases of keratomycosis. Surgery to remove the infected cornea is helpful in patients with deteriorating condition, in whom the initial medical therapy has failed. Topical and systemic antimycotic therapy, based on microbiological culture, is recommended as an adjunctive therapy for the surgical management of severe corneal mycotic abscesses.

Contact lens-related fungal keratitis

Contact lens-related fungal keratitis

Antimicrobial susceptibility of isolated pathogens from patients with contact lens-related bacterial keratitis in Crete, Greece: A ten-year analysis

PurposeTo evaluate the bacterial spectrum and antimicrobial susceptibilities of pathogens isolated from contact lens-related bacterial keratitis cases in a large academic Greek hospital. MethodsAll adult patients with positive corneal scrapings or contact lens culture between 2007 and 2016 at the University Hospital of Heraklion, Greece, were retrospectively identified through a local microbiology database and their medical records were reviewed. ResultsA total of 240 isolates were recovered from 131 patients with culture-proven contact lens-associated bacterial keratitis. The most common microorganism identified was Serratia marcescens (17.1% of total isolates), followed by Pseudomonas aeruginosa, Klebsiella spp. and coagulase-negative staphylococci (CoNS). Rates of aztreonam-resistant P. aeruginosa and erythromycin-resistant CoNS decreased in recent years, while the decrease in oxacillin-resistant CoNS was statistically significant (p=0.009). More than 90% of the isolated organisms (S. marcescens, P. aeruginosa, Klebsiella spp. and CoNS) were susceptible to ciprofloxacin or gentamicin. ConclusionGram-negative microorganisms are the most common causative pathogens of contact lens-related keratitis in the region of Crete. Topical antibacterials containing quinolones or gentamicin represent an effective empirical treatment for the majority of the cases. This is quite encouraging, considering that the present study was conducted in a country characterised by high antimicrobial resistance rates. However, culture-driven antimicrobial treatment is mandatory for this sight-threatening infection.

The differences between patient and optometrist experiences of contact lens hygiene education from the perspective of a Scottish university teaching hospital

BackgroundContact lens related keratitis is a frequent presentation to acute ophthalmology services. Patients often do not recall being counselled regarding the safe use of contact lenses therefore fail to comply with guidance.This study aimed to identify the content and format of advice given to patients with contact lens keratitis concerning appropriate hygiene practices, determine their compliance with this and finally characterise optometrist practices regarding contact lens advice provided to patients. MethodsAll adult patients presenting with contact lens related keratitis to the acute ophthalmology clinic were asked to complete a survey. Information was collected on lens type, format of advice received and compliance.Community optometrists were asked to complete an electronic survey on their contact lens review practices and routine patient education. ResultsAll patients surveyed recalled counselling on initiation of contact lenses; however 12% (6/50) were given no advice on return visits. This advice was in written format for 20% (10/50) of patients on initiation increasing to 32% (16/50) on renewal.Many patients slept (22%), showered (44%) or swam (36%) in lenses. 92% cleaned their contact lenses appropriately, but cases were washed infrequently (19% of cases cleaned < monthly) or with tap water (27%).All optometrists surveyed claimed to provide advice to patients in either written or verbal format for new and returning contact lens users. 49% (16/33) of optometrists gave written advice to patients on initial contact lens fitting, but only 1/33 continued with written advice for repeat customers. ConclusionThis study identified that although most patients were informed of appropriate hygiene requirements, compliance was poor. Optometrists regularly provide verbal advice but do not routinely offer written support and there is a mismatch between patient recollection and self-reported optometrist practice. It is suggested that patient education needs greater emphasis and both verbal and written information should be regularly provided on initial review and follow up assessments.

Diagnostic Utility of Polymerase Chain Reaction for Acanthamoeba in Contact Lens-related Keratitis with Epithelial Defects

Diagnostic Utility of Polymerase Chain Reaction for <i>Acanthamoeba</i> in Contact Lens-related Keratitis with Epithelial Defects

Contact Lenses and Infectious Keratitis

We review the evolution of contact lenses, risk factors for contact lens-related infectious keratitis, and updates on management. Infectious keratitis is still a devastating complication of contact lens use, with improper lens hygiene and use as significant risk factors. Cosmetic contact lenses have become popular among the younger generations. They can be obtained online without a doctor’s prescription or supervision, leading to an increased risk of serious infection. Topical antibiotics remain the best treatment for bacterial keratitis, but resistance to fourth-generation fluoroquinolones has increased. Fungal ulcers fare worse than bacterial ulcers, with no new commercially available topical treatments since topical natamycin. Despite the well-established link between water exposure of contact lenses and development of Acanthamoeba keratitis, patients still regularly expose their lenses to tap water. Corneal cross-linking, new methods for antimicrobial drug delivery, and novel antimicrobial targets represent the next frontiers in the treatment of infectious keratitis. Contact lens-related infectious keratitis remains a serious cause of ocular morbidity, with the rates of atypical causative organisms (Acanthamoeba and fungus) on the rise. Strategies for risk reduction include prevention through patient education; collaboration with industry to develop novel antimicrobials, lens materials, and care system products; and reporting of infections and illegal sale of contact lenses to regulatory agencies such as the United States Food and Drug Administration (FDA) and the Federal Trade Commission (FTC).

Contact lens-related keratitis and purulent corneal ulcers

To analyze cases of severe infectious keratitis and corneal ulcers associated with contact lenses (CL), to develop the optimum treatment strategy for these patients, and to identify areas for improvement in prevention, diagnosis and treatment methods. The study included 97 patients (103 eyes) with infectious keratitis and corneal ulcers associated with usage of contact lenses (CL) who were followed up from 2009 to 2016. Medical history of the patients was thoroughly analyzed. Scraping was taken from the cornea and conjunctiva of 61 patients for seeding. A three-step treatment strategy using 2-4 types of antimicrobial agents was developed. In 77 cases (79.3%) the occurrence of infection was associated with violation of the recommended rules of CL wearing and maintenance. Extended-wear CL had higher complication rate (62 patients) compared with daily-wear CL (17 patients) and orthokeratology (8 patients). Rigid CL was used in 1 case. In 9 patients CL type was unknown. Visual acuity upon admission varied from 1.0 to irregular perception of light projections; in 71 cases visual acuity was 0.3 or lower. According to microbiological examination, growth of microflora was observed in 20 cases (informational content 32.8%): Pseudomonas aeruginosa (9 eyes); Staphylococcus epidermidis, Acinetobacter species and mold fungi (3 eyes); Cryptococcus laurentii, Serratia marcescens, Burkholderia cepacia, Staphylococcus hominis, Candida (1 eye). In 10% of patients, non-bacterial infections (fungi and Acanthamoeba) were found. The average hospital stay duration was 15.2±8.9 days. Surgical treatment was required in 15 patients (15.5%) including 5 cases of penetrating keratoplasty. Visual acuity outcome was 0.3-1.0 in 67 cases; 3 patients had light perception with correct projection, and 2 - light perception with irregular projection. An effective treatment strategy for patients with CL-related keratitis and purulent corneal ulcers was developed. It is necessary to improve microbiological research methods. Creating a unified national database of such CL-related complications is advisable.

Diagnostic Approach to Ocular Infections Using Various Techniques From Conventional Culture to Next-Generation Sequencing Analysis.

Ocular infection is caused by both endogenous (resident) and exogenous (environmental) microbes. As the ocular surface interacts with both outer environment and its own resident microbiota, clinical ocular samples are predicted to contain a diverse set of microorganisms. Microscopy of sample smears is an important step in the diagnostic process of infectious diseases to interpret the culture results. Traditional culture techniques have several limitations in the detection and/or identification of uncharacterized bacteria of environmental origin. Molecular biological techniques, such as polymerase chain reaction of pathogen-specific virulence genes, 16S rRNA gene clone library analysis, and next-generation sequencing of 16S rDNA amplicons, compensate for diagnostic culture techniques in diagnosing infectious diseases. These techniques are expected to provide novel insights into the ocular microbiota and pathology of ocular infections. In this article, we describe various ocular infections, including contact lens-related keratitis, silicone buckle infection, and dacryocystitis, which were analyzed using molecular biological techniques. The advantages and disadvantages of these highly sensitive and inclusive microbiological detection systems for ocular infections are discussed.

Contact Lens-associated Keratitis by Elizabethkingia meningoseptica

Abstract Elizabethkingia meningoseptica is a Gram-negative bacillus. It is known for causing neonatal meningitis and pneumonia, sepsis in case of immunocompromised patients. It can be found in hospital and natural environments. It may exist in freshwater, salt water, and soil. It was previously known as Flavobacterium and Chryseobacterium meningosepticum.Contact lens-induced keratitis with E. meningoseptica which we are reporting is the second case report till date. It has striking resemblance with the case that was published earlier, with minimal difference in presentation, but significant difference in the antimicrobial sensitivity. Most importantly, we also found this infection in healthy individual with no underlying disease.Thus, we strongly support the case report that was published earlier, and though rare, this microbe should be considered as potential pathogen for contact lens-related keratitis, and increasing resistance to the antimicrobial agents should also be kept in mind.

Trends and Associations in Hospitalizations Due to Corneal Ulcers in the United States, 2002–2012

ABSTRACTPurpose: To estimate incidence, temporal trends, and factors associated with inpatient hospitalization due to corneal ulcers in the United States.Methods: Data on inpatient hospitalizations due to corneal ulcers between 2002 and 2012 were reviewed using the National Inpatient Sample. A literature review was conducted to identify the most common causes of corneal ulcers, and use of contact lenses.Results: An estimated 19,878 patients were seen in US emergency departments for evaluation of corneal ulcers in 2012. Rates of inpatient hospitalization due to corneal ulcers remained comparable over the decade (2003: 4.9, 95% confidence interval, CI, 3.0–6.7; 2012: 2.7, 95% CI 2.2–3.3 patients per million US population). Among those hospitalized for ophthalmic disease, patients holding public or no insurance (odds ratio, OR, 1.8 and 2.5, respectively, p<0.001), from low-income neighborhoods (OR 1.6, p < 0.001), and of older age (OR 3.4, p < 0.001) were more likely to be hospitalized for corneal ulceration. Medical conditions associated with hospitalization for corneal ulcer included history of keratitis (7.7%, p < 0.001), HIV infection (2.6%, p = 0.003), history of contact lens-related complications (2.5%, p < 0.001), and history of eye injury (2.5%, p = 0.001). Patients with a history of keratitis (p = 0.006) or rheumatoid arthritis (p = 0.001) were each twice as likely to receive a corneal transplant.Conclusions: Factors associated with hospitalization for corneal ulcer include insurance status in addition to history of contact lens-related disease and keratitis. Efforts should be made to address these factors prior to development of severe ulcers.

Acanthamoeba and Fusarium interactions: A possible problem in keratitis

The incidence of Acanthamoeba and Fusarium species has increased in contact lens-related infectious keratitis. They share several environments and cases of co-infection have been reported. The interaction between the amoebae and other microorganisms may result in significant changes for both, like increased virulence in mammalian hosts. In this study, we evaluated the interaction of three Acanthamoeba castellanii strains with Fusarium conidia and the possible implications on keratitis. F. conidia were internalized by A. castellanii strains and were able to germinate inside the amoebae. The co-culture with the live amoebae, as well as the amoebal culture supernatant and lysate, increased the fungal growth significantly. Moreover, live F. solani and its culture supernatant enhanced the survival of amoebae, but in a different way in each amoebal strain. The encystment of the A. castellanii strain re-isolated from rat lung was increased by the fungus. These results show that A. castellanii and F. solani interaction may have an important influence on survival of both, and specially indicate a possible effect on virulence characteristics of these microorganisms. These data suggest that the A. castellanii–F. solani interaction may cause severe impacts on keratitis.

Strategies for the prevention of contact lens-related Acanthamoeba keratitis: a review.

Acanthamoeba keratitis is a severe, often sight threatening, corneal infection which in Western countries is predominantly seen in daily wear of contact lenses. This review aims to summarise the pathobiology and epidemiology of contact lens-related Acanthamoeba keratitis, and to present strategies for prevention, particularly with respect to modifiable risk factors in contact lens wear. The virulence of Acanthamoeba and resistance to treatment in keratitis appears to be linked with the production of a low molecular weight protease MIP133 by the organism, in response to binding to corneal epithelial cells through a mannose binding protein, and to the ability of the organism to convert from the trophozoite to the resistant cyst form. Recent epidemiological studies in contact lens relate disease have confirmed the link between solution topping up and Acanthamoeba keratitis and have reinforced the importance of avoidance of tap water, either as part of the care for the contact lens or storage case, handling lenses with wet hands or showering while wearing lenses. In the most recent analysis from the USA, there were no strong effects for solution type, water source or water disinfection process. Wearer age, lens wear time and history to appear to be linked with Acanthamoeba keratitis. Daily disposable contact lens use would be expected to reduce the prevalence of Acanthamoeba disease although this is unproven. While Acanthamoeba keratitis remains challenging to diagnose and manage, strategies to limit the disease severity in contact lens wearers should include attention to recently identified risk factors, particularly those related to water contact. Public health awareness measures, the use of daily disposable contact lenses, a better understanding of the contribution of the host immunity and the development of standardised methods for culture of amoeba and testing of contact lens care systems against Acanthamoeba in the licensing process may be of value. Alternative treatments for the future may include those which target the mannose binding protein or the genes which control conversion to the cyst form.