与隐形眼镜相关的感染性角膜炎-埃及5年流行病学研究

目的：研究埃及Tanta大学医院与隐形眼镜相关的感染性角膜炎患者的不同流行病学特点,评估这类疾病各方面的特点,以提高患者对这类疾病的认识,找出可行的解决方案。

方法：选取我院2009-01/2013-12期间在眼科门诊就诊的所有角膜炎患者仔细检查,并对所有与隐形眼镜相关的感染性角膜炎患者进一步检查和调查。

结果：本研究期间,总共108 496位有不同主诉的患者中,1463例(1.3%)患有不同形式的角膜炎,其中151例(0.1%)为隐形眼镜相关感染性角膜炎。结果发现患有隐形眼镜相关感染性角膜炎常见的年龄群<30岁,大多数是学生(64%),家庭人数多且较为拥挤,农村居民高于城市居民,患者采用户外水源及污水处理不卫生。从病史分析发现：隐形眼镜相关感染性角膜炎通常为彻夜使用,储存或者配戴不卫生,或者隐形眼镜来源不安全,例如化妆品商店和理发店。结膜囊微生物培养结果提示阳性率92%,阴性率8%。大多数培养阳性的病例是由细菌和真菌混合感染引起,共53例(38.1%),单纯细菌感染43例(30.9%),真菌31例( 22.3%),阿米巴12例(8.6%)。

结论：与隐形眼镜相关的感染性角膜炎常见于学生群体,与农村生活、户外供水、不卫生的污水处理等危险因素有关。彻夜配戴、储存或配戴不卫生及隐形眼镜来源不安全都可增加隐形眼镜相关感染性角膜炎的发病率。     

Contact lens-related microbial keratitis: how have epidemiology and genetics helped us with pathogenesis and prophylaxis

Contact lens wear is a common predisposing factor in microbial keratitis and is one of the two preventable risk factors for corneal infection in a working age population. Our understanding of the prevention and prophylaxis of contact lens-related corneal infection is informed by recent epidemiological studies describing the incidence of and risk factors for the disease, the effect of causative organism on disease severity, and an appreciation of individual immune profiles in susceptibility to and severity of the disease. Although contemporary contact lenses have not reduced the overall incidence of keratitis, a reduction in morbidity may be achievable through recognition of appropriate risk factors in severe disease, including avoiding delays in presenting for appropriate treatment, and attention to storage case hygiene practise. Severe keratitis is most commonly associated with an environmental causative organism, and daily disposable lenses are associated with less severe disease. Pseudomonas aeruginosa remains the commonest cause of contact lens-related corneal infection probably because of its unique virulence characteristics and ability to survive in the contact lens/storage case/ocular environment. In two recent outbreaks of contact lens-related infections, there has been a strong association demonstrated with particular contact lens solutions. Since the recall of these specific contact lens solutions, the rate of Acanthamoeba keratitis has remained above the expected baseline, indicating unidentified risk factors that may include environmental exposures. Individual differences in susceptibility to microbial keratitis may be partly explained by differences in single-nucleotide polymorphisms in certain cytokine genes, particularly those with a proven protective role in corneal infection.     

Contact lens-related corneal infection: Intrinsic resistance and its compromise

Contact lenses represent a widely utilized form of vision correction with more than 140 million wearers worldwide. Although generally well-tolerated, contact lenses can cause corneal infection (microbial keratitis), with an approximate annualized incidence ranging from ~2 to ~20 cases per 10,000 wearers, and sometimes resulting in permanent vision loss. Research suggests that the pathogenesis of contact lens-associated microbial keratitis is complex and multifactorial, likely requiring multiple conspiring factors that compromise the intrinsic resistance of a healthy cornea to infection. Here, we outline our perspective of the mechanisms by which contact lens wear sometimes renders the cornea susceptible to infection, focusing primarily on our own research efforts during the past three decades. This has included studies of host factors underlying the constitutive barrier function of the healthy cornea, its response to bacterial challenge when intrinsic resistance is not compromised, pathogen virulence mechanisms, and the effects of contact lens wear that alter the outcome of host-microbe interactions. For almost all of this work, we have utilized the bacterium Pseudomonas aeruginosa because it is the leading cause of lens-related microbial keratitis. While not yet common among corneal isolates, clinical isolates of P. aeruginosa have emerged that are resistant to virtually all currently available antibiotics, leading the United States CDC (Centers for Disease Control) to add P. aeruginosa to its list of most serious threats. Compounding this concern, the development of advanced contact lenses for biosensing and augmented reality, together with the escalating incidence of myopia, could portent an epidemic of vision-threatening corneal infections in the future. Thankfully, technological advances in genomics, proteomics, metabolomics and imaging combined with emerging models of contact lens-associated P. aeruginosa infection hold promise for solving the problem - and possibly life-threatening infections impacting other tissues.     

Referral pathways and management of contact lens-related microbial keratitis in Australia and New Zealand

Background: We examine the referral pathways and treatment for contact lens‐related microbial keratitis in Australia and New Zealand. Methods: Cases were reported in May 2003–September 2004; data on presentation, referral and treatment collected from practitioners and via patient interview. Severity was graded, 1‐week cure rate estimated, delays in treatment and medications documented. Hospital and private clinic managements were compared. Results: A total of 297 eligible cases were reported; detailed information on treatment and referral pathways was available on a subset of these cases. Presentation was to optometrists (81/200, 41%), general practitioners (GPs) (69/200, 34%) or emergency departments (46/200, 23%). Optometrists referred to private ophthalmologists (47/79, 60%) more often than hospitals (27/79, 34%). GPs initiated treatment (39/68, 57%) but also referred to hospitals (22/68, 32%) and to private ophthalmologists (7/68, 10%). Of all cases, 67% (195/297) were managed in hospitals (29% admitted, 87/297). Hospitalized cases were predominantly managed with fortified aminoglycoside/cephalosporin (66/81, 82%) and others fluoroquinolones (168/195, 86%). Steroids were used in 36% (98/276) commencing on day 5 (median, interquartile range = 3–7). One‐week cure rate was 60% (49/82) in private clinics, 72% (62/86) for hospital outpatient cases and 37% (25/67, P < 0.001) for inpatient cases, which were more severe diseases (47%, 52% and 0% mild, respectively). Delays (≥12 h) receiving therapy were experienced by 33% (55/168) because of initial inappropriate treatment (48/55), time delays (7/55) but not remoteness (P = 0.6). Conclusions: The majority of treatment is via hospital clinics, but milder disease is managed in private clinics. The referral process via optometrists, GPs and emergency departments is generally efficient; however, one‐third of cases experienced some delays before receiving appropriate therapy highlighting the need for timely diagnosis.     

Clinical Presentation in Contact Lens-Associated Infectious Keratitis: A Study of Twenty Cases

Objective: To observe the clinical presentation and outcomes of corneal contact lens-related infectious keratitis, in order to provide a reference for clinical diagnosis and treatment. Methods: Patients who were hospitalized from July 2009 to June 2019 due to contact lens-related infectious keratitis were retrospectively reviewed. The risk factors of lens care, symptoms and signs, characteristics of corneal infection focus, results of etiological examination, treatment process and prognosis of the patients were collected and analyzed. Results: A total of 20 patients (23 eyes) were included in the study, 12 females and 8 males, with an average age of 21.4. Seventy-two percent of high-risk lens care (8/11) were wearing lenses for several days and washing the lenses in tap water. The most common clinical symptoms were foreign body sensation, pain, redness and vision loss. The ulcer in 15 eyes was located in the optic axis and paraoptic areas, and 8 eyes in the peripheral area. The positive rate of etiological examination was 35% (8/23).Acanthamoeba infection was found in 4 eyes, including 2 eyes combined with staphylococcus epidermidis infection, 3 eyes with pseudomonas aeruginosa infection and 1 eye with staphylococcus epidermidis infection. Sixteen eyes were successfully treated with drugs, and 7 eyes were successfully treated by surgery combined with drugs. Treatment outcomes were excellent in 8 eyes (35%), good in 9 eyes (39%), and poor in 6 eyes (26%). Conclusions: Wearing lenses for several days and washing them in tap water are the important risk factors of contact lens infection. Ulcers mainly occur in the optic axis and paraoptic areas. Acanthamoeba and pseudomonas aeruginosa are the most common pathogens. After timely and reasonable drug and surgical treatment, most of the patients can obtain satisfactory results.     

角膜接触镜相关感染性角膜炎20例临床特征

目的：观察角膜接触镜相关感染性角膜炎的临床特征及治疗转归,以期对临床诊疗提供参考。方法：回顾性观察2009年7月到2019年6月因配戴角膜接触镜发生感染性角膜炎而住院的患者,收集并分析患者的高危护理行为、症状体征、角膜感染灶的特点、病原学检查结果、治疗经过以及病情转归。结果：共20例患者（23眼）纳入本研究,女12例,男8例,平均年龄21.4岁。连续数日配戴及自来水清洗镜片占高危护理行为的72%（8/11）。最常见的临床症状是眼异物感、疼痛、眼红及视力下降。溃疡位于视轴区及视轴旁区15眼（65%）,位于周边区8眼（35%）。病原学检查阳性率为35%（8/23）,4眼为棘阿米巴感染,其中2眼合并表皮葡萄球菌感染;3眼为铜绿假单胞杆菌感染;1眼为表皮葡萄球菌感染。16眼（70%）药物治愈,7眼（30%）手术联合药物治愈。治疗效果佳为8眼（35%）,效果良好为9眼（39%）,效果差为6眼（26%）。结论：连续数日配戴及自来水清洗镜片是引发接触镜感染的重要危险因素;溃疡好发于视轴及视轴旁区;棘阿米巴原虫及铜绿假单胞杆菌是感染最常见的病原体。经过及时合理的药物及手术治疗,多数可获得满意疗效。     

Contact lens practice in Australia 1988–1989

Contact lens practitioners completed an annual survey of their prescribing patterns, usage of care solutions and attitudes to extended wear (EW). The survey period was July 1 1988 to June 30 1989 and the results were compared to those of previous, similar surveys. Many results were close to those in previous surveys, including the average number of pairs of lenses prescribed (95 new, 30 replacement), the proportion of contact lens fittings which were refits (40 per cent), the percentage of lenses prescribed which were soft (83 per cent) and the proportions of toric (soft 23 per cent, hard five per cent) and tinted (soft 39 per cent, hard 71 per cent) lenses prescribed. Results which differed markedly from previous surveys included the number of pairs of replacement lenses sold and the percentage of contact lens patients who were presbyopic. More than 90 per cent of lenses prescribed for EW were soft, although approximately 20 per cent of practitioners indicated that they would prefer to fit rigid gas permeable materials for EW. EW lenses were worn only on a true EW basis in six per cent of cases.     

Acanthamoeba keratitis cluster: an increase in Acanthamoeba keratitis in Australia

Background:  This study was undertaken in response to an increase in the number of patients treated for Acanthamoeba keratitis at a tertiary referral hospital in Brisbane, Australia. Incidence and patient characteristics were investigated over a 4-year period.
Methods:  A retrospective consecutive case series study was performed on patients with Acanthamoeba keratitis presenting to the Princess Alexandra Hospital between January 2003 and March 2007.
Results:  Nine cases of Acanthamoeba keratitis were identified over 12 months from March 2006 to March 2007 compared with four cases over the previous 37 months from January 2003 to February 2006. This was an increase from 0.07 cases per 1000 outpatient visits to 0.42 per 1000 ( P  = 0.003). Of the 13 cases, 11 patients used soft contact lenses of which two used monthly extended overnight wear silicone hydrogel lenses. Of the five patients who specified the type of contact lens solution they had used, three reported using AMO Complete Moistureplus Multipurpose solution, one reported using the AMO Complete Comfortplus Multipurpose solution and one was unsure which type of AMO Complete solution they were using.
Conclusions:  There has been a significant increase in incidence of cases of Acanthamoeba keratitis presenting to our institution. The type of contact lens solution and the use of silicon hydrogel lenses combined with extended overnight wear may play a role; however, the significance is unclear given the small numbers for analysis. Further study of incidence and patient characteristics is warranted to identify risk factors and causes for the rising incidence.     

Six-year review of Acanthamoeba keratitis in New South Wales, Australia: 1997-2002

AIM: To assess the incidence and risk factors for Acanthamoeba keratitis (AK), the diagnostic interval, and the efficacy and outcome of current treatment among the population of New South Wales, Australia. METHODS: A retrospective review was carried out of all cases of AK treated at the Sydney Eye Hospital between January 1997 and December 2002. RESULTS: Twenty patients were identified with a mean follow up of 24.8 +/- 21.5 months. Acanthamoeba keratitis constitutes 4.7% of severe infective keratitis treated at Sydney Eye Hospital. The mean interval from first presentation to diagnosis was 26.6 +/- 35.1 days overall; 17.2 +/- 33.1 days for those presenting directly to our unit (69% being diagnosed within 72 h of presentation), and 44.1 +/- 34.0 days for those first presenting elsewhere. Of those with a diagnostic delay >1 month, 57% had been mistakenly diagnosed with Herpes simplex keratitis. Sixteen (80%) wore contact lenses, and eight (40%) had additional risk factors including poor lens hygiene. Complications occurred in 16 (80%), with seven (35%) requiring surgical intervention. Visual acuity improved in 18 (90%), worsened in two patients (10%), and 75% achieved 6/12 or better at last follow up. CONCLUSIONS: Acanthamoeba keratitis is a rare infection, and contact lens wear remains the commonest association, with poor hygiene constituting significant additional risk. The visual outcome has improved with the availability of effective amoebicidal agents, but patients with a diagnostic delay and non-contact lens wearers are at increased risk of recurrent disease. A high index of clinical suspicion remains the most effective strategy in implementing early treatment, and enabling a favourable outcome.     

Contact lens practice in Australia 1987–1988

Contact lens practitioners were surveyed in September 1988 on their prescribing patterns, use of care solutions and attitudes to extended wear (EW). During the period July 1, 1987 to June 30, 1988, the responding practitioners prescribed an average of 95 new pairs of contact lenses and provided an average of 96 pairs of replacement lenses. Thirty-eight per cent of fittings were refits, 80 per cent of lenses prescribed were soft lenses, 25 per cent and 12 per cent of soft and hard lenses respectively were toric, and 39 per cent and 87 per cent of soft and hard lenses respectively were tinted. Hydrogen peroxide was the most popular method for disinfecting soft lenses. Over 85 per cent of the respondents were prepared to fit contact lenses for EW use under certain circumstances, but only 15 per cent of all lenses prescribed were for any type of EW. Over 90 per cent of lenses prescribed for EW were soft. The most commonly recommended frequency for regular EW lens replacement was six-monthly and the mean number of nights of overnight wear recommended by the practitioners was 4.5 nights per week.     

Surveillance of Contact Lens Related Microbial Keratitis in Australia and New Zealand: Multi-Source Case-Capture and Cost-Effectiveness

Purpose: To evaluate a multi-source surveillance system used in a 12-month study of contact lens related microbial keratitis in Australia and New Zealand. Methods: All practicing ophthalmologists and optometrists were surveyed on 6 occasions over 12 months via post or the Internet. Participation was defined as reporting at least once during the study period and the response rates represented those who responded on all six occasions. Cases were also detected through hospital audit. All ophthalmologists and a sub-group of optometrists were contacted by phone to elicit a response (active surveillance). The utilization and cost-effectiveness of active surveillance were compared to reports received via the post or the Internet. Case ascertainment and cost-effectiveness were compared for different sources of case capture. Results: The rate of participation for ophthalmologists was 95.8% (711/742) and 88.5% (657/742) responded for all reporting periods. Active surveillance was required for 63% (416/661) of responses in Australia (AU) and 73% (59/81) in New Zealand (NZ) at AUD23.14 per practitioner. Internet reporting was more widely used in New Zealand (NZ: 31% vs. AU:17%, p = 0.006) and was the most cost effective mode of reporting (AUD1.43 per practitioner). Postal reporting (AUD; AU:3.54,NZ:9.84 per practitioner) was under-utilized (3% of responses). Average start-up costs comprised 50% of study costs followed by active follow-up (42%), postal (6%) and Internet reporting (2%). Ophthalmologists (50.4%, 144/286 of cases) were the most cost-effective source of cases, followed by hospital audit (24.5%, 70/286) and optometry (25.1%, 72/286). Duplicate reporting occurred in 13% (37/286) of cases. Conclusions: High response rates were obtained by substantial resource commitment to active follow-up. Internet reporting was widely used and was cost-effective. Hospital audit and supplementary reporting by optometry were used for the first time in a study of contact lens related microbial keratitis, and contributed significantly to case capture.     

Contact lens-related corneal ulcers in compliant patients

PURPOSE: To report a case series of contact lens-related corneal ulcers in compliant patients with no apparent predisposing factors. DESIGN: Retrospective case series. METHODS: Charts of 70 patients with contact lens-related corneal ulcers from July 1999 to June 2002 were reviewed. Lens care hygiene and method of disinfection, as well as frequency of lens replacement, were recorded. Only patients who followed recommended guidelines for contact lens wear were included in the study. RESULTS: Of the 70 patients, 21 (30%) developed corneal ulcers despite being compliant with the guidelines for contact lens wear. All patients used multipurpose solutions for cleaning, disinfecting, and storing daily wear soft contact lenses. CONCLUSION: Standard lens care hygiene does not seem to be sufficient in preventing the development of corneal ulcers in patients using conventional and frequent replacement daily wear soft contact lenses.     

The Adherence of Pseudomonas aeruginosa to Soft Contact Lenses

The adherence of Pseudomonas aeruginosa to extended-wear soft contact lenses (EWSCLs) may be an important initial step in the pathogenesis of EWSCL-associated infectious keratitis. P. aeruginosa tend to adhere more to worn EWSCLs than unworn EWSCLs (P < 0.05). Normal tear components such as aqueous solutions of albumin, lysozyme, and lactoferrin all significantly enhance adherence of P. aeruginosa to unworn EWSCLs often by as much as 300%. The presence of a 1 % solution of sialic acid in the bathing medium significantly reduces the adherence of P. aeruginosa to both unworn and worn lenses. Inhibition of bacterial adherence could also be achieved with the addition of mucin (which contains terminal sialic acid residues in its major sugar chains). Therefore, selective adherence by P. aeruginosa to a specific sugar (sialic acid) may be important in the initial attachment of the bacterium to soft contact lenses.     

Contact lens fitting following corneal graft surgery

Contact lens fitting may be required following keratoplasty for either optical or thera‐peutic reasons. Optical indications for contact lens fitting include the correction of irregular astigmatism, high regular astigmatism, anisometropia and secondary aniseikonia, as well as simple ametropia, where the patient desires to wear contact lenses in preference to spectacles. Therapeutic lenses are not routinely fitted following kerate plasty, although this management is advised in certain cases, such as when there are protruding sutures or epithelial healing is impaired. Designing a contact lens for a patient who has undergone keratoplasty will require the practitioner to carefully assess all the relevant features of the corneal graft. In this regard, there are many factors that need to be considered including the diameter of the graft zone, the topographical relationship between the host cornea and donor cornea, the corneal (graft) toricity and the location of the graft. Special designs, such as reverse geometry lenses, or more complex contact lens modalities, such as piggyback contact lens systems, may be required to achieve success in fitting.     

1g/L氟米龙滴眼液联合软性角膜接触镜治疗丝状角膜炎

目的：探讨1g/L氟米龙滴眼液联合软性角膜接触镜治疗丝状角膜炎的疗效。

方法：确诊丝状角膜炎患者30例45眼,随机分为治疗组16例23眼、对照组14例22眼。治疗组取出丝状物后配戴软性角膜接触镜,点糖皮质激素眼液(1g/L氟米龙滴眼液)和人工泪液(玻璃酸钠眼液); 对照组取出丝状物后仅使用人工泪液(玻璃酸钠眼液)点眼。随访3mo,比较两组疗效。

结果：治疗组患者临床治疗总有效率22眼(96%),明显高于对照组17眼(77%),差异有统计学意义(P=0.046),且发现未对眼压有明显影响。

结论：1g/L氟米龙联合软性角膜接触镜治疗丝状角膜炎有较好疗效。     

Extended Wear Silicone Contact Lenses in Children with Cataracts

Thirty-two patients, ranging in age from three weeks to 22 years, were fitted with an extended wear 100% silicone lens. The longest period of time a lens remained in the eye without being removed was 120 days. Most lenses were worn an average of six weeks before cleaning was required. No cases of infection or corneal edema were observed that required discontinuing use of the lens.