Association of single nucleotide polymorphisms of interleukins-1ß, -6, and -12B with contact lens keratitis susceptibility and severity.

PURPOSE: To investigate whether single nucleotide polymorphisms (SNPs) in interleukin (IL)-1ß, IL-6, and IL-12ß are associated with the susceptibility and severity of contact lens-related keratitis. DESIGN: Retrospective, case control study. PARTICIPANTS: One hundred twelve cases of keratitis and 225 controls were recruited from studies conducted at Moorfields Eye Hospital and in Australia during 2003 through 2005. METHODS: Buccal swab samples were collected on Whatman FTA cards and were mailed by post for analysis. IL-1ß (-31), IL-6 (-174, -572, -597), and IL-12B (3'+1158) genotypes were analyzed with pyrosequencing and analyzed using a regression model for susceptibility (sterile, microbial keratitis, controls) and severity. Statistical significance was set at 0.05. MAIN OUTCOME MEASURES: The relative risk of developing contact lens-related keratitis and more severe forms of the disease based on allele, genotype, and haplotype associations. RESULTS: Carriers of IL-6 SNPs were more likely to experience moderate and severe events compared with those with nonmutated genotypes (-174 heterozygous: odds ratio [OR], 3.1; 95% confidence interval [CI], 1.1-8.3; homozygous: OR, 6.4; 95% CI, 1.4-28.4; -174/-597: OR, 4.1; 95% CI, 1.6-11.0). More severe keratitis and microbial keratitis were less likely to occur in wearers with the nonmutated IL-6 haplotype (severity OR, 0.4 [95% CI, 0.2-0.7]; microbial OR, 0.6 [95% CI, 0.4-0.9]). Wearers carrying an IL-12B SNP had an increased risk of sterile keratitis (OR, 9.7; 95% CI, 1.2-76.9) compared with controls. CONCLUSIONS: The IL-6 SNPs are known to reduce protein expression of this cytokine and thus ocular immune defense, and carriers of these SNPs were more likely to experience more severe and microbial keratitis, suggesting that IL-6 decreases the severity and susceptibility of contact lens-related keratitis. Carriers of a functional SNP of IL-12B that is known to increase IL-12 expression and stability are more likely to experience sterile keratitis, suggesting that this is associated with the intense inflammatory reaction that occurs in this condition.

Comparison of ocular comfort, vision, and SICS during silicone hydrogel contact lens daily wear.

OBJECTIVES: The aim of this study was to investigate the relationship between solution-induced corneal staining (SICS) and silicone hydrogel contact lens comfort and vision. METHODS: A retrospective analysis of a series of open-label studies were conducted with 24 groups of approximately 40 participants, each wearing 1 of 6 silicone hydrogel contact lenses with 1 of 4 lens care products bilaterally for 3 months of daily wear. The presence of SICS and subjective ocular ratings were collected at 2 weeks and at 1 and 3 months. RESULTS: A total of 1,051 participants were enrolled. The participants with SICS rated significantly less favorably than did the participants without SICS for comfort during the day (7.9±1.7 vs. 8.5±1.4, P=0.03), comfort at the end of the day (6.6±2.1 vs. 7.4±1.9, P=0.03), overall dryness (7.4±1.9 vs. 8.0±1.7, P=0.04), dryness at the end of the day (6.7±2.2 vs. 7.5±2.1, P=0.01), feelings of burning and stinging (8.5±2.0 vs. 8.9±1.8, P=0.02), and overall vision (8.2±1.6 vs. 8.7±1.3, P<0.001). CONCLUSIONS: The participants with SICS had lower subjective comfort and vision compared with those who did not experience SICS.

Grading of corneal and conjunctival staining in the context of other dry eye tests.

PURPOSE: To describe the Oxford Scheme for grading ocular surface staining in dry eye and to discuss optimization of stain detection using various dyes and filters. Also, to propose a sequence of testing for dry eye diagnosis. METHODS: The grading of corneal and conjunctival staining is described, using the Oxford Scheme, including biomicroscopy, optical filters, illumination conditions, and the characteristics of and instillation techniques used for, selected clinical dyes. RESULTS: A series of panels, labeled A-E, in order of increasing severity, reproducing the staining patterns encountered in dry eye, are used as a guide to grade the degree of staining seen in the patient. The amount of staining seen in each panel, represented by punctate dots, increases by 0.5 of the log of the number of dots between panels B to E. The use of the vital dyes fluorescein, lissamine green, and rose Bengal is described; fluorescein and lissamine green, used in conjunction with appropriate absorption filters, are recommended for use in clinical trials. The placement of staining in relation to the sequence of other diagnostic tests is discussed. CONCLUSIONS: The monitoring and assessment of corneal and conjunctival staining can be greatly enhanced by the use of a grading scale, controlled instillation of dyes, and standard evaluation techniques. This is of particular benefit in clinical trials, where ocular surface staining is commonly employed as an outcome measure

Contact lens-related adverse events and the silicone hydrogel lenses and daily wear care system used.

OBJECTIVE: To investigate the incidence of adverse events related to the use of varying silicone hydrogel contact lens and lens solution combinations. METHODS: Individuals with myopia (N = 558) participated in 1 or more of approximately 40-participant trials in a matrix of 20 silicone hydrogel contact lens and lens-solution combinations. Visits were at baseline, 2 weeks, 1 month, and 3 months. The mean study completion rate was 90% of the expected participant-months (final data set: 840 lens-solution combinations and 2271 participant-months). Adverse events were reported as the first occurrence of each type per 100 participant-months for each lens-solution combination. RESULTS: The rate of all corneal infiltrative events (CIEs) was 3.1 per 100 participant-months (range, 0-10.5), and the rate of symptomatic CIEs was 1.7 per 100 participant-months (range, 0-10.5), including 1 case of microbial keratitis (0.04 per 100 participant-months). Rates for CIEs differed substantially among solution groups, with hydrogen peroxide having the lowest rate (0.6 per 100 participant-months; range, 0-0.9). The rate was 0.8 per 100 participant-months (range, 0-8.0) for superior epithelial arcuate lesions, which varied by lens type, 0.04 per 100 participant-months (1 case only) for corneal erosion, and 0.4 per 100 participant-months (range, 0-2.0) for contact lens papillary conjunctivitis, which was modified by type of solution. The rate of solution-induced corneal staining for all lens-solution combinations was 4.7 per 100 participant-months (range, 0-23) and varied significantly based on lens-solution combination (P < .001). CONCLUSIONS: The frequency of adverse events varied with silicone hydrogel contact lens and lens solution combinations, with hydrogen peroxide having the lowest incidence of CIEs and solution-induced corneal staining, indicating that lens material and design, type of solution, and solution-lens interactions are likely contributing factors in this mode of lens wear.