Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9057, USA.
Cornea. 2010 Oct;29(10):1075-85. doi: 10.1097/ICO.0b013e3181d103bb.
To identify the pathophysiological changes produced by contact lens wear that predispose the cornea to infection and search for prospective modifiable risk factors that could reduce the incidence of this critical complication in millions of patients worldwide.
Significant experimental and clinical publications are reviewed, and the results of ongoing studies are presented.
Pseudomonas aeruginosa (PA) is the most common pathogen causing lens-related infectious keratitis over 3 decades. Contact lens wear can increase the risk of infection by increasing surface cell PA binding, thereby promoting invasion between broken tight junctions and initiating direct intracellular invasion mediated by lens-induced membrane lipid rafts. Prevention of upregulation of specific surface-binding receptors for PA with concomitant increase in infection risk is a zero damage game where independent interactions among lens type, mode of wear, oxygen transmissibility, polymer, and toxic effects of associated care solutions ideally should collectively produce no increased ability for PA to attach and/or to invade, thus minimizing the risk for lens-associated infections. The specific hypothesis tested is, "no increased epithelial surface damage... no increased PA binding or invasion... no increased risk for infection." Testing of this new paradigm has been performed in vitro and in animal and human clinical trials and correlated clinically with relative risk results from robust current epidemiological studies. Results to date clearly support the use of lens-related increases in PA binding (bench) as a noninvasive clinical predictor of risk for lens-related infection in subsequent large-scale population studies (bedside). Currently, results suggest that use of common commercial multipurpose lens care solutions with soft lenses may alone significantly increase infection risk by enhancing lens-related PA binding as compared with use of nonpreserved solutions (hydrogen peroxide). Clinical testing also shows that only peroxide solutions show significant disinfection capability against amoebic cysts. Further case-control studies to examine relative risk for infection by lens type and lens care solution are urgently needed.
Millions of patients are dependent on contact lenses for vision worldwide; over 3 decades, lens use has increased, although risk for lens-related infection has remained stubbornly unchanged. Unfortunately, recent introduction of a new generation of hyper-oxygen transmissible lenses used with traditional multipurpose lens care solutions has not lowered overall risks for lens-related infections; however, similar lenses used with nonpreserved care solutions (peroxide) recently demonstrated no significant increases in PA binding in a 1-year clinical trial. Collectively, these findings along with the urgent need for amoebic cysticidal disinfection have led to a current recommendation to patients to use nonpreserved (hydrogen peroxide) care solutions in soft lens wear.
确定隐形眼镜佩戴引起的病理生理变化，使角膜容易感染，并寻找潜在的可改变的风险因素，以降低全球数百万患者发生这种严重并发症的风险。
回顾了重要的实验和临床出版物，并介绍了正在进行的研究结果。
假单胞菌（PA）是 30 多年来导致与镜片相关的传染性角膜炎的最常见病原体。隐形眼镜的佩戴会增加表面细胞与 PA 结合的风险，从而促进紧密连接破裂之间的侵袭，并通过镜片诱导的膜脂筏启动直接细胞内侵袭。用伴随感染风险增加的特定表面结合受体的上调来预防 PA 的上调是一个零损伤的游戏，其中镜片类型、佩戴方式、氧气通透性、聚合物以及相关护理溶液的毒性作用之间的独立相互作用理想情况下不应该导致 PA 附着和/或侵袭能力的增加，从而将与镜片相关的感染风险降到最低。经过测试的具体假设是，“上皮表面损伤没有增加……PA 结合或侵袭没有增加……感染风险没有增加。”已经在体外、动物和人体临床试验中对这一新范式进行了测试，并与来自当前强大的流行病学研究的相对风险结果进行了临床相关分析。迄今为止的结果清楚地支持将与镜片相关的 PA 结合增加（床旁）用作后续大规模人群研究中与镜片相关感染风险的非侵入性临床预测因子（床边）。目前，结果表明，与使用非保存溶液（过氧化氢）相比，使用普通商业多用途镜片护理液与软性镜片一起使用可能会单独显著增加感染风险，从而增强与镜片相关的 PA 结合。临床测试还表明，只有过氧化物溶液对阿米巴囊具有显著的消毒能力。迫切需要进一步进行病例对照研究，以检查镜片类型和镜片护理液对感染的相对风险。
全世界有数百万人依赖隐形眼镜来改善视力；30 多年来，隐形眼镜的使用有所增加，尽管与镜片相关的感染风险仍然保持不变。不幸的是，最近引入的新一代高氧通透性镜片与传统多用途镜片护理液一起使用，并未降低与镜片相关的感染的总体风险；然而，最近在一项为期 1 年的临床试验中，使用非保存护理液（过氧化物）的类似镜片并未显示 PA 结合的显著增加。综上所述，以及对阿米巴囊杀菌消毒的迫切需求，目前建议患者在软性隐形眼镜佩戴时使用非保存（过氧化氢）护理液。
