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Ilyas M, Stapleton F, Willcox MDP, Henriquez F, Peguda HK, Rayamajhee B, Zahid T, Petsoglou C, Carnt NA. Epidemiology of and Genetic Factors Associated with Acanthamoeba Keratitis. Pathogens 2024; 13:142. [PMID: 38392880 PMCID: PMC10892102 DOI: 10.3390/pathogens13020142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/14/2024] [Accepted: 01/31/2024] [Indexed: 02/25/2024] Open
Abstract
Acanthamoeba keratitis (AK) is a severe, rare protozoal infection of the cornea. Acanthamoeba can survive in diverse habitats and at extreme temperatures. AK is mostly seen in contact lens wearers whose lenses have become contaminated or who have a history of water exposure, and in those without contact lens wear who have experienced recent eye trauma involving contaminated soil or water. Infection usually results in severe eye pain, photophobia, inflammation, and corneal epithelial defects. The pathophysiology of this infection is multifactorial, including the production of cytotoxic proteases by Acanthamoeba that degrades the corneal epithelial basement membrane and induces the death of ocular surface cells, resulting in degradation of the collagen-rich corneal stroma. AK can be prevented by avoiding risk factors, which includes avoiding water contact, such as swimming or showering in contact lenses, and wearing protective goggles when working on the land. AK is mostly treated with an antimicrobial therapy of biguanides alone or in combination with diaminidines, although the commercial availability of these medicines is variable. Other than anti-amoeba therapies, targeting host immune pathways in Acanthamoeba disease may lead to the development of vaccines or antibody therapeutics which could transform the management of AK.
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Affiliation(s)
- Muhammad Ilyas
- Primary & Secondary Healthcare Department, Punjab 54000, Pakistan; (M.I.)
| | - Fiona Stapleton
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Mark D. P. Willcox
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Fiona Henriquez
- School of Health and Life Sciences, The University of the West of Scotland, Glasgow G72 0LH, UK
| | - Hari Kumar Peguda
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Binod Rayamajhee
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Tasbiha Zahid
- Primary & Secondary Healthcare Department, Punjab 54000, Pakistan; (M.I.)
| | | | - Nicole A. Carnt
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
- Centre for Vision Research, Westmead Institute for Medical Research, Sydney, NSW 2145, Australia
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Konda N, Chakrabarti S, Garg P, Willcox MDP. Association of Single-Nucleotide Polymorphisms in Interleukin Genes with Microbial Keratitis in a South Indian Population. Pathogens 2022; 11:1387. [PMID: 36422638 PMCID: PMC9692714 DOI: 10.3390/pathogens11111387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/12/2022] [Accepted: 11/19/2022] [Indexed: 05/03/2024] Open
Abstract
BACKGROUND To examine the relationship between single-nucleotide polymorphisms (SNPs) in interleukin (IL) genes and keratitis and its clinical manifestations. METHODS SNPs in IL1B, IL6, CXCL8, IL10, and IL12B were analysed. Differences in frequencies of alleles, genotypes and haplotypes between cases and controls as well as associations between SNPs and clinical variables were calculated by χ2 tests with odds ratios. RESULTS The minor homologous genotype in IL1B rs16944 (p = 0.036; odds ratio (OR) = 2.063, 95% confidence interval (CI): 1.048-4.061) and CXCL8 rs4073 (p = 0.041; OR = 0.463, 95% CI: 0.224-0.956) and the heterologous genotypes in IL6 rs1800795 (p = 0.046; OR = 0.563, 95% CI: 0.326-0.972) and IL12B rs2569254 (p = 0.0446; OR = 0.557, 95% CI: 0.314-0.989) or rs730691 (p = 0.0051; OR = 0.451, 95% CI: 0.260-0.784) were associated with keratitis. The minor genotype of rs16944 was associated with severe infection (p = 0.046). The heterologous genotype in rs2569254 was associated with hospital admission, photophobia, and mode of contact lens wear (p ≤ 0.041). The heterologous genotype in rs730691 was associated with blurred vision, discharge, anterior chamber reaction, and mode of wear (p ≤ 0.047). CONCLUSIONS This study demonstrates that SNPs in IL1B and CXCL8 are associated with risk of developing keratitis. The study also found relationships between SNPs and clinical measures of keratitis. The potential for ethnic differences in frequency of SNPs and their association with keratitis should be followed up using different populations.
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Affiliation(s)
- Nagaraju Konda
- School of Optometry and Vision Science, University of New South Wales, Sydney 2052, Australia
- Brien Holden Vision Institute, Sydney 2052, Australia
- School of Medical Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Subhabrata Chakrabarti
- Brien Holden Eye Research Centre, L. V. Prasad Eye Institute, Hyderabad 500034, Telangana, India
| | - Prashant Garg
- The Cornea Institute, L. V. Prasad Eye Institute, Hyderabad, Telangana 500034, India
| | - Mark D. P. Willcox
- School of Optometry and Vision Science, University of New South Wales, Sydney 2052, Australia
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Stapleton F, Shrestha GS, Vijay AK, Carnt N. Epidemiology, Microbiology, and Genetics of Contact Lens-Related and Non-Contact Lens-Related Infectious Keratitis. Eye Contact Lens 2022; 48:127-133. [PMID: 35192567 DOI: 10.1097/icl.0000000000000884] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2021] [Indexed: 01/14/2023]
Abstract
ABSTRACT 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.
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Affiliation(s)
- Fiona Stapleton
- School of Optometry and Vision Science, UNSW Sydney, Australia
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Stapleton F. Contact lens‐related corneal infection in Australia. Clin Exp Optom 2021; 103:408-417. [DOI: 10.1111/cxo.13082] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 03/31/2020] [Indexed: 12/20/2022] Open
Affiliation(s)
- Fiona Stapleton
- School of Optometry and Vision Science, The University of New South Wales, Sydney, Australia,
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CLEAR - Contact lens complications. Cont Lens Anterior Eye 2021; 44:330-367. [DOI: 10.1016/j.clae.2021.02.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 02/01/2021] [Indexed: 12/20/2022]
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Carnt NA, Pang I, Burdon KP, Calder V, Dart JK, Subedi D, Hardcastle AJ. Innate and Adaptive Gene Single Nucleotide Polymorphisms Associated With Susceptibility of Severe Inflammatory Complications in Acanthamoeba Keratitis. Invest Ophthalmol Vis Sci 2021; 62:33. [PMID: 33755043 PMCID: PMC7991962 DOI: 10.1167/iovs.62.3.33] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Purpose Over a third of patients with Acanthamoeba keratitis (AK) experience severe inflammatory complications (SICs). This study aimed to determine if some contact lens (CL) wearers with AK were predisposed to SICs due to variations in key immune genes. Methods CL wearers with AK who attended Moorfields Eye Hospital were recruited prospectively between April 2013 and October 2014. SICs were defined as scleritis and/or stromal ring infiltrate. Genomic DNA was processed with an Illumina Low Input Custom Amplicon assay of 58 single nucleotide polymorphism (SNP) targets across 18 genes and tested for association in PLINK. Results Genomic DNA was obtained and analyzed for 105 cases of AK, 40 (38%) of whom experienced SICs. SNPs in the CXCL8 gene encoding IL-8 was significantly associated with protection from SICs (chr4: rs1126647, odds ratio [OR] = 0.3, P = 0.005, rs2227543, OR = 0.4, P = 0.007, and rs2227307, OR = 0.4, P = 0.02) after adjusting for age, sex, steroids prediagnosis, and herpes simplex keratitis (HSK) misdiagnosis. Two TLR-4 SNPs were associated with increased risk of SICs (chr9: rs4986791 and rs4986790, both OR = 6.9, P = 0.01). Th-17 associated SNPs (chr1: IL-23R rs11209026, chr2: IL-1β rs16944, and chr12: IL-22 rs1179251) were also associated with SICs. Conclusions The current study identifies biologically relevant genetic variants in patients with AK with SICs; IL-8 is associated with a strong neutrophil response in the cornea in AK, TLR-4 is important in early AK disease, and Th-17 genes are associated with adaptive immune responses to AK in animal models. Genetic screening of patients with AK to predict severity is viable and this would be expected to assist disease management.
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Affiliation(s)
- Nicole A Carnt
- School of Optometry and Vision Science, University of New South Wales (UNSW), Sydney, Australia.,Westmead Institute for Medical Research, Westmead, New South Wales, Australia.,University College London (UCL) Institute of Ophthalmology, London, United Kingdom
| | - Ignatius Pang
- School of Biotechnology and Biomolecular Sciences, University of New South Wales (UNSW), Sydney, Australia
| | - Kathryn P Burdon
- Menzies Institute for Medical Research, University of Tasmania, Tasmania, Australia
| | - Virginia Calder
- University College London (UCL) Institute of Ophthalmology, London, United Kingdom
| | - John K Dart
- University College London (UCL) Institute of Ophthalmology, London, United Kingdom.,Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Dinesh Subedi
- School of Optometry and Vision Science, University of New South Wales (UNSW), Sydney, Australia.,School of Biological Sciences, Monash University, Clayton, Australia
| | - Alison J Hardcastle
- University College London (UCL) Institute of Ophthalmology, London, United Kingdom
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Szczotka-Flynn LB, Shovlin JP, Schnider CM, Caffery BE, Alfonso EC, Carnt NA, Chalmers RL, Collier S, Jacobs DS, Joslin CE, Kroken AR, Lakkis C, Pearlman E, Schein OD, Stapleton F, Tu E, Willcox MDP. American Academy of Optometry Microbial Keratitis Think Tank. Optom Vis Sci 2021; 98:182-198. [PMID: 33771951 PMCID: PMC8075116 DOI: 10.1097/opx.0000000000001664] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
SIGNIFICANCE Think Tank 2019 affirmed that the rate of infection associated with contact lenses has not changed in several decades. Also, there is a trend toward more serious infections associated with Acanthamoeba and fungi. The growing use of contact lenses in children demands our attention with surveillance and case-control studies. PURPOSE The American Academy of Optometry (AAO) gathered researchers and key opinion leaders from around the world to discuss contact lens-associated microbial keratitis at the 2019 AAO Annual Meeting. METHODS Experts presented within four sessions. Session 1 covered the epidemiology of microbial keratitis, pathogenesis of Pseudomonas aeruginosa, and the role of lens care systems and storage cases in corneal disease. Session 2 covered nonbacterial forms of keratitis in contact lens wearers. Session 3 covered future needs, challenges, and research questions in relation to microbial keratitis in youth and myopia control, microbiome, antimicrobial surfaces, and genetic susceptibility. Session 4 covered compliance and communication imperatives. RESULTS The absolute rate of microbial keratitis has remained very consistent for three decades despite new technologies, and extended wear significantly increases the risk. Improved oxygen delivery afforded by silicone hydrogel lenses has not impacted the rates, and although the introduction of daily disposable lenses has minimized the risk of severe disease, there is no consistent evidence that they have altered the overall rate of microbial keratitis. Overnight orthokeratology lenses may increase the risk of microbial keratitis, especially secondary to Acanthamoeba, in children. Compliance remains a concern and a significant risk factor for disease. New insights into host microbiome and genetic susceptibility may uncover new theories. More studies such as case-control designs suited for rare diseases and registries are needed. CONCLUSIONS The first annual AAO Think Tank acknowledged that the risk of microbial keratitis has not decreased over decades, despite innovation. Important questions and research directions remain.
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Affiliation(s)
| | | | | | | | - Eduardo C Alfonso
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Nicole A Carnt
- School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia
| | | | - Sarah Collier
- U.S. Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Deborah S Jacobs
- Massachusetts Eye and Ear, Cornea Service, Harvard Medical School, Boston, Massachusetts
| | - Charlotte E Joslin
- Department of Ophthalmology and Visual Science, College of Medicine, Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, Illinois
| | - Abby R Kroken
- School of Optometry, University of California, Berkeley, Berkeley, California
| | | | - Eric Pearlman
- Departments of Ophthalmology, and Physiology and Biophysics, University of California, Irvine, Irvine, California
| | - Oliver D Schein
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Fiona Stapleton
- School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia
| | - Elmer Tu
- University of Illinois Eye and Ear Infirmary, Chicago, Illinois
| | - Mark D P Willcox
- School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia
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Szczotka-Flynn L. Contact Lens-Related Microbial Keratitis and Host Genetics. Eye Contact Lens 2020; 46:327-328. [PMID: 33119983 DOI: 10.1097/icl.0000000000000735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Loretta Szczotka-Flynn
- Department of Ophthalmology & Visual Sciences, Case Western Reserve University; and Contact Lens Service, University Hospitals of Cleveland Eye Institute
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9
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Konda N, Kaur I, Garg P, Chakrabarti S, Willcox MDP. Toll-like receptor gene polymorphisms in patients with keratitis. Cont Lens Anterior Eye 2020; 44:101352. [PMID: 32723620 DOI: 10.1016/j.clae.2020.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 01/10/2023]
Abstract
OBJECTIVE To investigate differences in SNPs in TLR genes between people who had keratitis and controls in an Indian population. METHODS 145 cases of keratitis and 189 matched controls were recruited. DNA was extracted from peripheral blood. Single nucleotide polymorphisms (SNP) in TLR2 (n = 6), TLR4 (n = 15), TLR5 (n = 13) and TLR9 (n = 10) were analysed. The risk of developing keratitis was assessed based on allele, genotype and haplotype associations. RESULTS For all cases of keratitis, the TLR4 SNP rs4986791 TC genotype frequency was significantly higher in cases (p = 0.006, OR = 1.96, 95 % CI 1.19-3.2). Including cases of only microbial keratitis (MK) revealed that genotypes in TLR2 SNP rs5743706 TA (p = 0.0001; OR = 8.61; 95 % CI 2.59-28.56)), TLR4 SNP s4986791 TC (p = 0.002; OR = 2.65; 95 % CI 1.39-5.07) were significantly more common for MK, whereas the TLR5 SNP rs2241096 A allele (p = 0.00316, OR = 0.42, 95 % CI 0.2-0.9286) and GA genotype (p = 0.016; OR = 0.45; 95 % CI 0.23-0.86) was significantly less common in MK cases. The TLR2 SNP rs5743706 genotype TA was significantly less common in the sterile keratitis (SK) group (p = 0.004, OR = 0.43, 95 %CI 0.24-0.77). Haplotype analysis of MK compared to controls showed that TLR2 AT was more common in controls (p = 0.003); TLR4 ACAC was more common in cases (p = 0.004); TLR5 TGGCA was more common in controls (p = 0.001). CONCLUSION The present study revealed multiple associations between variants across TLR genes, which may have implications for understanding the underlying host factors, risk of developing keratitis and molecular pathogenesis in keratitis.
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Affiliation(s)
- Nagaraju Konda
- School of Optometry and Vision Science, University of New South Wales, Australia; Brien Holden Vision Institute, Sydney, Australia; School of Medical Sciences, University of Hyderabad, Hyderabad, Telangana, India
| | - Inderjeet Kaur
- Brien Holden Eye Research Centre, L. V. Prasad Eye Institute, Hyderabad, Telangana, India
| | - Prashant Garg
- The Cornea Institute, L. V. Prasad Eye Institute, Hyderabad, Telangana, India
| | - Subhabrata Chakrabarti
- Brien Holden Eye Research Centre, L. V. Prasad Eye Institute, Hyderabad, Telangana, India
| | - Mark D P Willcox
- School of Optometry and Vision Science, University of New South Wales, Australia.
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Carnt NA, Cipriani V, Stapleton FJ, Calder V, Willcox MD. Association study of single nucleotide polymorphisms in IL-10 and IL-17 genes with the severity of microbial keratitis. Cont Lens Anterior Eye 2019; 42:658-661. [DOI: 10.1016/j.clae.2019.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 06/19/2019] [Accepted: 06/25/2019] [Indexed: 01/20/2023]
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Chao C, Akileswaran L, Cooke Bailey JN, Willcox M, Van Gelder R, Lakkis C, Stapleton F, Richdale K. Potential Role of Ocular Microbiome, Host Genotype, Tear Cytokines, and Environmental Factors in Corneal Infiltrative Events in Contact Lens Wearers. Invest Ophthalmol Vis Sci 2019; 59:5752-5761. [PMID: 30516819 PMCID: PMC6281277 DOI: 10.1167/iovs.18-24845] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose The purpose of this study was to explore differences in genotype, ocular surface microbiome, tear inflammatory markers, and environmental and behavioral exposures in soft contact lens (SCL) wearers with and without a history of corneal infiltrative events (CIEs). Methods Nine SCL wearers with a recent CIE and nine age-, sex-, and SCL material- and modality-matched controls were enrolled. The Contact Lens Risk Survey, slit-lamp examination data, basal tears, conjunctival microbial cultures, and peripheral blood samples were collected. Tear inflammatory mediator concentrations, genomic DNA from swabs, and whole exome sequencing of blood samples were quantified. Results There were no marked differences in SCL wear behaviors or exposures between case and control subjects. Predominant organisms detected among case and control subjects were Staphylococcus, Propionibacterium, Streptococcus, and Corynebacterium. Marginally higher levels of Neisseria were found in three of nine cases but zero of nine control samples (P = 0.056). A potentially deleterious missense single nucleotide polymorphism (SNP) variant in IL-6 Signal Transducer (IL6ST) was found in seven of eight cases and zero of nine controls (rs2228046; P = 0.03). The concentration of tear IL-6 was significantly higher in cases (4.5 [range, 2.1 to 6.2] pg/mL) versus controls (3.5 [range, 2.5 to 6.6] Pg/mL; = 0.02). Conclusions Tear IL-6 concentration was higher, and SNP variants were detected in subjects with a history of CIEs compared with healthy controls. The synthesis, signaling, and ocular surface cytokine concentration of IL-6 may be related to susceptibility to CIE. A larger study population is required to further explore relationships between genetic variations, the ocular surface microbiome, inflammatory mediators, and environmental exposures.
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Affiliation(s)
- Cecilia Chao
- Tufts Medical Center, Center for Translational Ocular Immunology, Boston, Massachusetts, United States.,University of New South Wales School of Optometry and Vision Science, Kensington, New South Wales, Australia
| | - Lakshmi Akileswaran
- Department of Ophthalmology, University of Washington Medical School, Seattle, Washington, United States
| | - Jessica N Cooke Bailey
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Institute for Computational Biology, Cleveland, Ohio, United States
| | - Mark Willcox
- University of New South Wales School of Optometry and Vision Science, Kensington, New South Wales, Australia
| | - Russell Van Gelder
- Department of Ophthalmology, University of Washington Medical School, Seattle, Washington, United States
| | - Carol Lakkis
- Johnson & Johnson Vision Care, Inc., Jacksonville, Florida, United States
| | - Fiona Stapleton
- University of New South Wales School of Optometry and Vision Science, Kensington, New South Wales, Australia
| | - Kathryn Richdale
- University of Houston College of Optometry, Houston, Texas, United States
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Carnt N, Samarawickrama C, White A, Stapleton F. The diagnosis and management of contact lens-related microbial keratitis. Clin Exp Optom 2017; 100:482-493. [PMID: 28815736 DOI: 10.1111/cxo.12581] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/22/2017] [Accepted: 05/27/2017] [Indexed: 01/10/2023] Open
Abstract
Contact lens-associated microbial keratitis poses a diagnostic dilemma for optometrists on two fronts. The distinction between sterile inflammation and microbial infection is often blurred. In addition, there is a requirement with nearly 50 per cent of the Australian and New Zealand optometric profession being therapeutically endorsed, to distinguish between cases of infection that can be managed in the community verses those that require escalation to public hospitals that have access to laboratory diagnostic tools and advanced imaging techniques, such as in vivo confocal microscopy. Pattern recognition and incorporation of knowledge of aetiology and risk factors assists optometrists to decide on optimal management strategies. Skilled optometrists will utilise emerging diagnostic and therapeutic technologies to ensure safe management strategies and better outcomes for these cases.
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Affiliation(s)
- Nicole Carnt
- School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia.,The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Chameen Samarawickrama
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Andrew White
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Fiona Stapleton
- School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
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13
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Chao C, Richdale K, Jalbert I, Doung K, Gokhale M. Non-invasive objective and contemporary methods for measuring ocular surface inflammation in soft contact lens wearers - A review. Cont Lens Anterior Eye 2017; 40:273-282. [PMID: 28602547 DOI: 10.1016/j.clae.2017.05.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 05/25/2017] [Accepted: 05/29/2017] [Indexed: 10/19/2022]
Abstract
Contact lens wear is one of the primary risk factors for the development of ocular surface inflammatory events. The purpose of this review is to examine and summarize existing knowledge on the mechanisms of contact lens related ocular surface inflammation and the evidence for the effectiveness of current objective methods to measure ocular surface inflammation. Contact lens wear is postulated to trigger an inflammatory response on the ocular surface due to mechanical, chemical, hypoxic stress, or by the introduction of microbes and their toxins. Apart from the traditional signs of inflammation, such as swelling, oedema, redness and heat, on the ocular surface, other methods to measure ocular surface inflammation in sub-clinical levels include tear inflammatory mediator concentrations, conjunctival cell morphology, and corneal epithelial dendritic cell density and morphology. Tear inflammatory mediator concentrations are up- or down-regulated during contact lens wear, with or without the presence of associated inflammatory events. There is higher conjunctival cell metaplasia observed with contact lens wear, but changes in goblet cell density are inconclusive. Dendritic cell density is seen to increase soon after initiating soft contact lens wear. The long term effects of contact lens wear on dendritic cell migration in the cornea and conjunctiva, including the lid wiper area, require further investigation. Currently patient factors, such as age, smoking, systemic diseases and genetic profile are being studied. A better understanding of these mechanisms may facilitate the development of new management options and strategies to minimize ocular surface inflammation related to contact lens wear.
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Affiliation(s)
- Cecilia Chao
- College of Optometry, State University of New York, New York, USA; School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Kathryn Richdale
- College of Optometry, State University of New York, New York, USA
| | - Isabelle Jalbert
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Kim Doung
- College of Optometry, State University of New York, New York, USA
| | - Moneisha Gokhale
- Deakin Optometry, Deakin University, 75 Pigdons Road, Waurn Ponds, Victoria, 3216, Australia.
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Navarra CO, Robino A, Pirastu N, Bevilacqua L, Gasparini P, Di Lenarda R, Crovella S. Caries and Innate Immunity: DEFB1 Gene Polymorphisms and Caries Susceptibility in Genetic Isolates from North-Eastern Italy. Caries Res 2016; 50:589-594. [DOI: 10.1159/000450965] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/20/2016] [Indexed: 11/19/2022] Open
Abstract
Background: The DEFB1 gene, encoding for the constitutively expressed human β-defensin 1 (hBD1) antimicrobial peptide is a potential candidate when studying genetic susceptibility to caries. DEFB1 genetic variations have been reported as contributing to hBD1 production impairment, leading to a greater susceptibility to be infected by oral pathogens, also leading to periodontitis. Methods: We analysed 5 DEFB1 polymorphisms, namely 3 functional single-nucleotide polymorphisms (SNPs) at the 5′-untranslated region (UTR), -52G>A (rs1799946), -44C>G (rs1800972), and -20G>A (rs11362), 2 SNPs at the 3′-UTR, c*5G>A (rs1047031) and c*87A>G (rs1800971) SNP located in potential miRNA binding sites, looking for possible correlations with the risk to develop caries in 654 adult subjects from isolated populations of north-eastern Italy. Dental caries prevalence was evaluated with the DMFT (decayed, missing, filled teeth) index, calculated after an accurate oral examination. DEFB1 SNP genotyping was performed with an Illumina 370k high-density SNP array. Results: Two DEFB1 SNPs were significantly associated with the DMFT index: the strongest association emerged from rs11362 SNP (p = 0.008). In particular G/G homozygous individuals showed a higher DMFT index compared to both G/A heterozygous and A/A homozygous individuals; rs1799946 SNP was also significantly associated with DMFT (p = 0.030), and individuals homozygous for the T allele had a higher DMFT value compared to heterozygous C/T and homozygous C/C individuals. Conclusions: Our study replicated, on a larger number of individuals, previous findings showing the association between two 5′-UTR SNPs in the DEFB1 gene and DMFT, suggesting that these polymorphisms could be considered as potential markers for assessing the risk to develop caries.
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Carnt N, Stapleton F. Strategies for the prevention of contact lens-relatedAcanthamoebakeratitis: a review. Ophthalmic Physiol Opt 2015; 36:77-92. [DOI: 10.1111/opo.12271] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 11/23/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Nicole Carnt
- Save Sight Institute; University of Sydney; Sydney Australia
- School of Optometry and Vision Science; University of New South Wales; Sydney Australia
| | - Fiona Stapleton
- School of Optometry and Vision Science; University of New South Wales; Sydney Australia
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Robaei D, Carnt N, Minassian DC, Dart JK. Therapeutic and Optical Keratoplasty in the Management of Acanthamoeba Keratitis. Ophthalmology 2015; 122:17-24. [DOI: 10.1016/j.ophtha.2014.07.052] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 05/20/2014] [Accepted: 07/29/2014] [Indexed: 11/30/2022] Open
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