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Objective: To describe a patient diagnosed with Exophiala jeanselmei keratitis., Methods: We report a case of a patient who developed infectious keratitis following laser in situ keratomileusis and chronic topical steroid use for approximately six months in both eyes. An atypical infiltrate containing dark pigmentation was noted in the left eye on the initial presentation. During treatment, the infiltrates of the right eye began to exhibit a similar pigmentation., Results: Early treatment with topical antifungals was initiated in the left eye and later in the right eye once culture results returned. Both eyes recovered with good vision after approximately one month., Conclusions: Patients treated with postoperative topical corticosteroids should be cautioned of potential adverse effects of chronic use and have close follow-up. If infectious keratitis develops, particularly after two weeks, then atypical organisms, such as fungi, should be considered. In addition, our case highlights the significance of recognizing and associating dark-pigmentation with fungal etiologies., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2024 Contact Lens Association of Ophthalmologists.)

Purpose: To ascertain the frequency of coinfections in Acanthamoeba keratitis, the nature of copathogens involved, and to analyze the implications in the context of current research on amoebic interactions., Methods: A retrospective case review from a Tertiary Care Eye Hospital in South India. Smear and culture data for coinfections in Acanthamoeba corneal ulcers were collected from records over a 5-year period. The significance and relevance of our findings in the light of current research on Acanthamoeba interactions were analyzed., Results: Eighty-five cases of culture-positive Acanthamoeba keratitis were identified over a 5-year period (43 of them being coinfections). Fusarium was most commonly identified species, followed by Aspergillus and the dematiaceous fungi. Pseudomonas spp was the commonest bacterial isolate., Conclusion: Coinfections with Acanthamoeba are common at our centre, and account for 50% of Acanthamoeba keratitis. The diverse nature of the organisms involved in coinfections suggest that such amoebic interactions with other organisms are probably more widespread than recognized. To the best of our knowledge, this is the first documentation from a long-term study of pathogen diversity in Acanthamoeba coinfections. It is possible that Acanthamoeba itself may be virulence enhanced and secondary to the co-organism, breaching the ocular surface defenses in an already compromised cornea. However, observations from the existing literature on Acanthamoeba interactions with bacteria and certain fungi are based mainly on nonocular or nonclinical isolates. It would be illuminating if such studies are performed on Acanthamoeba and coinfectors from corneal ulcers-to ascertain whether interactions are endosymbiotic or virulence enhanced through amoebic passage., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2023 Contact Lens Association of Ophthalmologists.)

We report a rare case of dematiaceous fungus colonization in the therapeutic bandage contact lens (BCL), in an eye with peripheral ulcerative keratitis. Bandage contact lens removal and appropriate treatment resulted in improvement of the visual acuity and prevented the spread of fungus to the underlying ocular structures. Microbiological evaluation of the BCL showed dematiaceous fungal filaments, and the fungus was identified as Bipolaris species. In patients with pigmented plaque-like lesions, with BCL in situ, dematiaceous fungus on the undersurface of the BCL should be kept in mind. Patient education regarding the importance of frequent BCL replacement, proper ocular hygiene, and timely follow-up should be emphasized.

Purpose: To report a case of Nocardia farcinica keratitis in a pediatric contact lens wearer., Methods: Case report and literature review., Results: A pediatric contact lens wearer was initially misdiagnosed with a poorly healing corneal abrasion after swimming with his contact lenses. On examination at our center, he was found to have a 2.5 by 2.5 mm corneal infiltrate with feathery margins. Microbiology revealed N. farcinica keratitis, which was treated with topical amikacin. The patient returned to his baseline visual acuity after treatment., Conclusions: Nocardia keratitis can be misdiagnosed because of its low prevalence, especially in young patients. Prompt diagnosis is important for proper management in these cases. The infection resolved in our patient with prompt diagnosis and treatment with topical amikacin eye drops.

Objectives: To evaluate the risk factors, causative microorganisms, and presenting features of infection in patients with contact lens-associated microbial keratitis (CLAMK) admitted to a tertiary referral center in Turkey., Methods: A retrospective review of the medical records of 62 patients who were diagnosed as CLAMK in our clinic between 2012 and 2018 was conducted., Results: The mean age of the patients (22 men and 40 women) at the time of diagnosis was 24.5±8.3 years (range, 16-48). The mean best-corrected visual acuity (BCVA) was 0.7±0.9 log of minimal angle of resolution (logMAR) (0-3) before treatment and increased to 0.1±0.1 logMAR (0-0.4) at the end of the follow-up. All patients, except one using rigid gas-permeable CL, were frequent replacement soft CL users. Thirty-one (50%) patients declared overnight wear, and 37 (58.9%) patients declared showering or swimming in CLs regularly. Cultures of either corneal scrapings or CL materials were positive in 40 (64.5%) eyes, 12 (19.4%) of which had mixed infections. Thirteen strains of microorganisms were demonstrated, among which there were seven (53.8%) gram-negative bacteria, one (7.7%) gram-positive bacteria, four (30.7%) fungi, and Acanthamoeba (7.7%). The most common pathogen was Pseudomonas aeruginosa, followed by Serratia marcescens and Stenotrophomonas maltophilia. According to culture results, P. aeruginosa infections were associated with significantly worse BCVA. Keratitis foci were either centrally or paracentrally located in 39 (62.9%) eyes, and 16 eyes (25.8%) presented with hypopyon., Conclusion: Along with growing number of CL users, CLAMK constitutes an important problem with possibly worse visual outcomes. Thus, in addition to meticulous treatment, management of risk factors and behavioral modifications is crucial.

Purpose: To compare the infectious contact lens-related corneal ulcer (CLRU) and non-CLRU cases at Saint Louis University., Methods: Retrospective review of corneal ulcer cases identified by search of the ophthalmology and microbiology department databases between 1999 and 2016., Results: Six hundred seventy-seven cases of corneal ulcers were identified, of which 46% were CLRU. CLRU cases were seen more commonly in younger patients (P<0.001) and women (P=0.03) than non-CLRU cases. Many of the infections were vision-threatening as defined by central/paracentral location (73% CLRU and 71% non-CLRU [P=0.60]) and large size of ulcer >2 mm in 36% CLRU and 51% non-CLRU (P=0.002). Causative pathogen in cultured CLRU was predominately Pseudomonas species (44%, P<0.001 vs. the non-CLRU group), other gram-negative (6%), gram-positive (33%), fungi (13%), and Acanthamoeba (5%). Comparatively, cultured non-CLRU was predominately gram-positive (64%, P<0.001 vs. the CLRU group), gram-negative (26%), and fungi (11%). The combined oxacillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus isolates were 35% and 34%, respectively. Despite the progressive increase in the number of corneal ulcers seen, the annual trend for any one particular organism for either CLRU cases or non-CLRU cases did not change significantly., Conclusions: Most of the cases were non-CLRU. CLRU was disproportionately associated with Pseudomonas species and non-CLRU with Staphylococcal species. Fungal infections were predominately caused by filamentous organisms in both groups. Acanthamoeba keratitis was exclusively associated with CL use.

Objectives: To study the microbial profile, antibiotic susceptibility pattern, risk factors, therapeutic trends, and clinical outcomes for microbial keratitis (MK) in a tertiary health care center., Methods: All cases with suspected bacterial keratitis that were followed at consultation from September 2007 to August 2015 were included. Microbial cultures were obtained and patients were managed following an internal protocol., Results: Two hundred thirty-five patients were included, with a mean age of 50.01±20.73 years. We obtained a 38.4% culture-positive rate, with higher proportion of gram-positives (70.8%). The commonest agents were Staphylococcus aureus (23.1%), Corynebacterium macginleyi (20.0%), and Pseudomonas aeruginosa (13.8%). Fluoroquinolone susceptibility was 97%, with no trend toward its decrease. A total of 95.7% had local risk factors, being trauma and contact lens wear the most common (28.9% each), with different age and pathogens distributions (P<0.001). Topical fluoroquinolones were first-line treatment in 99%, in association with aminoglycosides in 81.6%. Good initial response was registered in 95.9%, but 4.1% needed to step up treatment to fortified antibiotics, mainly if Pseudomonas (P=0.021). Good outcome was achieved in 81.8%, negatively affected by exposure and herpetic keratitis (P<0.001), central location (P=0.01), presence of Tyndall (P<0.001), corneal edema (P<0.001), and worse initial best-corrected visual acuity (P<0.001), but not Pseudomonas isolate (P=0.724)., Conclusions: Gram-positives are the most frequent pathogens and shifting trends in the isolate distribution or emergence of resistant strains were not demonstrated. The susceptibility to first-line antibiotic agents remained high. We suggest a more aggressive approach to P. aeruginosa cases or MK presenting with poor outcome variables.

Purpose: Propionibacterium acnes is a commensal bacteria whose pathogenicity in infectious keratitis is unclear. In this study, we report infectious keratitis cultured with P. acnes and evaluate its clinical characteristics., Methods: All cases of infectious keratitis submitted to the microbiology laboratory of St. Mary's Hospital of Seoul between January 2013 and April 2014 were reviewed. Nonpretreated cases that were positive for P. acnes were identified, and clinical characteristics and treatment outcomes were studied., Results: Of 132 cultures submitted to the microbiology laboratory, 89 (67.4%) were positive for growth, and a total of 16 (17.9%) of the 89 cases yielded P. acnes in culture medium. Infectious keratitis that was positive for P. acnes was generally small (62.5%) with deep stromal infiltration (81.25%) and a peripheral location (56.25%). The average incubation period was 11.06±5.76 days, and the average time to reepithelialization was 23.50+13.52 days. All the cases of P. acnes evaluated in this report responded well to medical treatment., Conclusions: Infectious keratitis with P. acnes is not uncommon and can be confused with other Gram-positive cocci. Thus, P. acnes should be suspected in small-sized keratitis with an unusually long incubation period.

Objective: To evaluate the clinical effect of combined topical autologous serum eye drops (ASEs) and silicone hydrogel contact lens (CLs) for the treatment of corneal persistent epithelial defects (PEDs) after infectious corneal ulcers., Methods: We conducted a retrospective chart review of 12 patients with postinfectious corneal PEDs who were unsuccessfully treated with conventional medical management and were then treated with combined topical 20% (v/v) ASEs and silicone hydrogel CLs from July 1, 2011, to June 30, 2014. The corneal ulcers were all initially managed with antibiotic eye drops until the infiltrates resolved but the lesions failed to epithelialize. The clinical effects of the combined treatment were evaluated., Results: The PEDs healed in all 12 patients within 2 weeks. The combined treatment was associated with an improvement of best-corrected visual acuity (BCVA) at the final 3-month follow-up examination. All patients responded well to the combined treatment and no adverse events were noted in any patient., Conclusions: The combined use of silicone hydrogel CLs and ASEs can successfully treat postinfectious corneal PEDs and prevent continuous corneal melting during acute disease.

Objective: To determine the characteristics of infectious keratitis caused by Kocuria spp., Methods: Retrospective case series. Information included demographic data, medical history, risk factors associated with infectious keratitis, clinical characteristics, microbiological results and drug sensitivity, clinical course, management, and visual outcomes., Results: Eight patients were included (7 females and 1 male; mean age, 66.2 years; age range, 42-84 years). All patients presented risk factors for infectious complications, such as filamentous keratitis, dry eye, blepharitis, and persistent corneal edema. In all cases, ulcers were classified as severe. The infection resolved with medical treatment in one eye only. One case was treated with amniotic membrane graft. Two patients required keratoplasty (lamellar and penetrating), and one case needed sclerokeratoplasty. In three cases, the keratitis was severe enough to require evisceration. The final visual acuity ranged from 20/25 to no light perception., Conclusions: Bacterial keratitis by Kocuria spp. is a rare infection that may have an unexpected clinical course and possible serious outcomes. This pathogen should be considered in patients with unusual clinical course. Local or systemic immune compromise in the genesis of the disease must also be taken into account, and ophthalmologists should be more suspicious in this vulnerable group of patients.

Introduction: Infectious keratitis is a common ophthalmic disease with the potential for severe ocular morbidity. Multiple studies have described various risk factors for the development of infectious keratitis. The purpose of this study was to analyze the seasonal variation in the presentation of infectious keratitis, and also seasonal changes in its etiologies and risk factors., Methods: A retrospective chart review was performed on consecutive patients presenting to the emergency department at our tertiary care urban hospital center who were diagnosed with infectious keratitis from 2008 to 2013. A chi-square analysis was performed to determine whether a significant seasonal variation existed between the month, season, frequency of presentation of ulcers, and other risk factors., Results: A total of 155 patients-53 men and 102 women-with a mean age of 40 (range, 3-97; median, 36) diagnosed with infectious keratitis were included in the analysis. Sixty-nine (44.5%) ulcers presented in the summer, 19 (12.3%) in the fall, 34 (21.9%) in the winter, and 33 (21.3%) in the spring (P<0.0001). Seventeen (11%) patients experienced diabetes mellitus, 60 (39%) were contact lens wearers, 12 (8%) ulcers occurred in the setting of trauma, and 19 (12%) patients underwent previous ocular surgery. A total of 92 ulcers were cultured, of which 53.8% were positive in the summer, 42.9% in the fall, 55.0% in the winter, and 42.1% in the spring. A significant seasonal variation in the frequency of 1 organism, Pseudomonas aeruginosa, was identified (P=<0.0001); up to 47.6% of culture-positive ulcers in the summer were P. aeruginosa positive, whereas cultures in the remaining seasons were 0, 9.1% and 12.5% positive for this organism., Discussion: The summer months have a higher frequency of infectious keratitis and P. aeruginosa positivity in this study. Possible factors leading to this increased summer presentation include warmer temperatures, higher humidity, and greater ocular exposure to water. Clinicians should increase their vigilance and education to high-risk patients during these periods and potentially modify empiric treatment regimens.

Purpose: The most feared complication of contact lens (CL) wear is microbial keratitis (MK), even though its incidence remains low. This study aimed to identify the risk factors of CL-related MK in a large, prospective, multicenter case-control study., Methods: A multicenter case-control study was designed. The CL-related MK subpopulation (Case) was compared with healthy CL wearers (Control) using a 52-item anonymous questionnaire designed to determine subject demographics and lens wear history. Univariate and multivariate logistic regression analyses were performed to compare both groups., Results: The study enrolled 499 cases and 508 controls. The risk factors associated with the greatest increased odds of CL-related MK were as follows: using disinfecting solution more than 3 months (odds ratio [OR]=1.94), cosmetic CL wear and use of multipurpose disinfection solution (1.37 each), overnight wear, and soft lens use (OR=1.24 each). The protective factors associated with the greatest reduction in OR were fitting by an ophthalmologist (OR=0.73) and hyperopia versus myopia (OR=0.75)., Conclusions: The infectious determinants were linked to the type of lenses, hygiene routine, CL handling, disinfecting solution, and storage case. This study aimed to highlight the increasingly CL-related MK, which likely occurs because of lack of patient information regarding basic rules of hygiene and CL care and handling.

Objective: To report a case of fungal keratitis caused by Alternaria in a 49-year-old female who developed an acute onset of eye infection after ocular trauma caused by an olive leaf., Methods: The clinical presentation, microbiological diagnosis, and therapeutic approaches are reported., Results: The patient was referred to our university hospital clinic with corneal abscess in her left eye. Before the start of an empirical antibacterial therapy (both topical and systemic), a swab of the cornea was obtained which at microscopic examination revealed a few fragments of hyphal elements, probably for the paucity of material collected. After one week, the corneal abscess had increased in size, and the corneal stroma was filled with filamentous structures similar to fungal hyphae. Oral and topical voriconazole was administered because of the clinical picture and the response of microbiological laboratory whose examination of the material removed from the anterior chamber showed numerous hyphal fragments identified by culture as Alternaria spp. The corneal abscess healed in two weeks, but the patient now has a corneal scar and is awaiting a corneal transplant., Conclusions: Ophthalmologists and microbiologists must take fungi into greater consideration as a possible cause of keratitis as they are emerging as the cause of this infectious disease in many countries. Voriconazole spreads well in the eye and is effective in the cure of fungal keratitis including those caused by Alternaria.

Objective: To demonstrate a case of infectious crystalline keratopathy (ICK) caused by Pseudomonas fluoresecens (PF)., Methods: Case report description., Results: A 15-year-old female contact lens wearer presented complaining of eye pain and redness in the left eye. The patient reported that she had suffered a corneal scratch a few months earlier, which was treated by her family physician, and that she had felt some discomfort since then. The biomicroscopy showed a central corneal abscess with a crystalline appearance, stromal edema, the Tyndall effect, and abundant fibrin in the anterior chamber. A diagnosis of ICK was made. The culture was positive for gram-negative PF. Pseudomonas fluoresecens was sensitive to cephalosporins, quinolones, and tobramycin., Conclusions: No cases of ICK caused by PF have been reported previously. Two previous studies reported that the gram-negative Pseudomonas aeruginosa caused ICK. Unlike other ICK cases in which there is minimal stromal inflammation, the patient presented with an intense inflammatory reaction in the anterior chamber.

Objectives: Paracoccus yeei is an environmental bacterium suspected to be responsible for ocular infections. In this study, culture-based and polymerase chain reaction (PCR) sequencing-based investigations of a corneal scraping specimen confirmed P. yeei keratitis in one contact lens wearer., Methods: A 34-year-old male patient, who was a contact lens wearer, presented with a unilateral corneal ulcer. A corneal scraping was performed to conduct a microbiological investigation. Disease progress was favorable after a 5-week topical treatment, which combined rifampicin, ciprofloxacine, tobramycine, and dexamethasone. The final visual acuity of the right eye was 5/10 with correction, limited by a central corneal scar., Results: Culturing the corneal scraping specimen yielded P. yeei, which was also directly detected by PCR sequencing the bacterial 16S rDNA in the presence of negative controls. The P. yeei isolate was susceptible to ticarcillin, with a minimal inhibitory concentration (MIC) of <4 mg/L of ceftazidime (MIC of 0.5 mg/L), imipenem (MIC < 0.5 mg/L), gentamycin (MIC of 0.5 mg/L), tobramycin (MIC < 0.06 mg/L), rifampicin (MIC < 0.125 mg/L), ciprofloxacin (MIC < 0.5 mg/L), and colimycin (MIC < 2 mg/L). The isolate was resistant to fosfomycine with a MIC 32 > mg/L., Conclusions: P. yeei is a new cause of keratitis that must be diagnosed by a laboratory analysis of corneal scrapings due to the potentially poor outcome of infection.

Objective: To present a case of bacterial keratitis caused by Elizabethkingia meningosepticum in an eye after trauma., Method: Case report., Result: A 45-year-old woman was referred to our cornea clinic for keratitis, which had developed following nonpenetrating eye trauma from a tree branch. Cultures from a corneal smear demonstrated heavy growth of E. meningosepticum. Treatment with a combination of topical moxifloxacin and topical trimethoprim/polymyxin B effectively controlled the corneal ulcer. Corneal infection resolved within 2 months, but a central corneal scar and vascularization remained., Conclusions: E. meningosepticum is an opportunistic bacterium and gives rise to severe systemic infections in immunocompromised patients. Ocular infections caused by this bacterium are extremely rare in the literature. To our knowledge, this is the first report of posttraumatic keratitis caused by E. meningosepticum.

Objective: To report the therapeutic practice patterns of silicone hydrogel (SiH) bandage soft contact lenses (BSCL) and the resultant rate of microbial keratitis (MK)., Methods: A retrospective case series of patients treated with therapeutic BSCLs for ocular surface disease from January 2006 to January 2009 in a tertiary care cornea practice. All patients had a history of ocular surface disease., Results: Seventy-four patients were treated with a therapeutic SiH BSCL (102 intervals of use) for complicated ocular surface disease. Two patients developed infectious corneal infiltrates (2/102, 2.0%) [corrected]. Two of 3 MK episodes were in patients with limbal stem-cell deficiency (2/102, 2.0%)., Conclusions: Therapeutic SiH BSCLs were safely used in most patients. However, results suggest that prophylactic antibiotic use did not eliminate the risk for MK with SiH BSCL use in patients with chronic ocular surface disease.

Objective: To report an unusual case of keratitis in a cosmetic contact lens wearer caused by two rare organisms., Method: Case report., Results: A 14-year-old cosmetic contact lens user presented with a paracentral corneal ulcer in her right eye. The cosmetic lenses were bought online. The cultures from corneal scrapings and contact lenses demonstrated heavy growth of Chryseobacterium meningosepticum and Delftia acidovorans. The treatment with topical ciprofloxacin and fortified gentamicin was effective, and the infection resolved with corneal scar after 5 weeks., Conclusion: Use of cosmetic contact lenses and buying them online is a fairly common practice among teenagers. This can lead to serious eye infection as in this case. To our knowledge, this is the first report of contact lens-related keratitis simultaneously involving these two rare organisms.

Objectives: To report a rare case of spontaneous Stenotrophomonas maltophilia keratitis in a diabetic patient., Methods: A case report of this rare ulcerative keratitis case with an extensive review of the literature., Results: The patient's corneal infiltrate was successfully cultured and a rare ocular organism identified. The patient's presentation and course and the response to empiric treatment are discussed., Conclusions: Consideration of the antibiotic combination chosen here can be considered in the treatment of S. maltophilia keratitis after appropriate cultures are taken and the organism isolated.

Objectives: To determine whether carriage of microbes on the contact lens or ocular surfaces during extended wear (EW) with soft hydroxyethyl methacrylate (HEMA)-based contact lenses predisposes the wearer to adverse events., Methods: Participants (non-contact lens wearers) were enrolled in a clinical study involving wear of HEMA-based hydrogel lenses on a six night EW basis with weekly replacement. Type and number of bacteria colonizing the lower lid margins, upper bulbar conjunctiva, and contact lenses during EW after one night, 1 week, 1 month, and thereafter every 3 months for 3.5 years were determined. The association of bacteria with adverse responses was compared between carriers (defined as having significant microbes cultured from two or more samples with 1 year) and noncarriers, and the strength of the association was estimated using multivariate logistic regression., Results: Carriers of gram-positive bacteria on lenses (particularly coagulase negative staphylococci or Corynebacterium spp.) were approximately three and eight times more likely to develop contact lens-induced peripheral ulcers (CLPUs) and asymptomatic infiltrates (AIs), respectively. Staphylococcus aureus was most frequently isolated from lenses during CLPU. Carriers of gram-negative bacteria on lenses were five times more likely to develop contact lens-induced acute red eye (CLARE). Haemophilus influenzae was isolated most frequently from lenses during CLARE and AI events., Conclusions: Bacterial carriage on contact lenses during EW predisposes the wearer to the development of corneal inflammatory events including CLARE, CLPU, and AI.

Purpose: To report with morphologic and phylogenetic speciation the first case from Israel of Pythium insidiosum keratitis associated with contact-lens wear., Methods: Case report and literature review., Results: A 21-year-old man with a history of contact-lens use and water exposure was hospitalized in Israel for a corneal ulcer. The ulcer progressed despite intensive antibiotics. He flew home to the United States for further care. Examination revealed a corneal ulcer with hypopyon. The infection progressed despite intensive medical therapy, and a therapeutic penetrating keratoplasty was performed. Histology and cornea cultures from the host cornea revealed sparsely septate, branching hyphae, consistent with P. insidiosum. DNA sequencing of the Pythium isolate supported the clinical history that the infection was acquired outside of the United States. Despite intensive medical therapy and a second corneal transplant, the ulcer progressed, ultimately requiring enucleation., Conclusion: This is the first reported case of culture-proven, contact lens-related Pythium keratitis originating from Israel. Pythium is a fungus-like, aquatic oomycete found in tropical climates. Human pythiosis is uncommon but associated with high morbidity. Case reports describe surgical cure of Pythium keratitis, but this case recurred despite two penetrating keratoplasties and maximal antifungal therapy. In cases of presumed fungal keratitis that do not respond to antifungals, the fungus should be sent for speciation because early surgical intervention is the only means to save the eye in ocular pythiosis.

Objective: To evaluate the ophthalmic community's current opinions of the management of bacterial keratitis and usage of the currently available ophthalmic antibiotics., Methods: An anonymous questionnaire was mailed to ophthalmologists in California, Florida, Illinois, and Missouri. The results were tabulated and analyzed statistically., Results: Six hundred twenty-nine usable questionnaires (10.3%) were returned. In the management of corneal ulcers, 42.2% of comprehensive ophthalmologists and 75.3% of cornea specialists perform Gram stains some of the time. A total of 73.3% of comprehensive ophthalmologists and 93.7% of cornea specialists perform corneal cultures some of the time. A total of 88.8% of comprehensive ophthalmologists and 76% of cornea specialists initiate treatment with the newer fluoroquinolone antibiotics. A total of 12.1% of comprehensive ophthalmologists and 41% of cornea specialists would select fortified antibiotics for the treatment of corneal ulcers. The percentage of those who feel that fortified antibiotics are superior ranges from 17.7% for comprehensive ophthalmologists to 33.3% for cornea specialists. A total of 65.7% of comprehensive ophthalmologists indicate that the newer fluoroquinolones have impacted their practices, and 58.3% indicate that they represent an improvement over older fluoroquinolones., Conclusions: Most responding ophthalmologists initiate empiric therapy with the newer fluoroquinolone antibiotics for corneal ulcers, forgoing Gram staining and culturing. However, respondents are not universally sanguine about the newer fluoroquinolones. The practice patterns and opinions on antibiotics differ almost universally between comprehensive ophthalmologists and cornea specialists. Larger, more detailed surveys and more specific analyses would help to further establish the factors that lead to differing management choices and opinions.

Objective: To describe a patient who developed contact-lens associated Fusarium sp. keratitis associated with use of sample kits of ReNu with MoistureLoc purchased after worldwide recall of the product from the market., Methods: The patient's history, clinical presentation, and laboratory workup were reviewed., Results: In April 2008, a 64-year-old woman with a 45-year history of contact lens wear presented with a large central corneal infiltrate after receiving empiric antibiotic treatment before referral. Corneal and contact lens cultures revealed Fusarium sp. The patient had been using sample kits of ReNu with MoistureLoc purchased from a dollar store to clean her lenses., Conclusions: Although a worldwide recall of ReNu with MoistureLoc occurred in May 2006, the product may still be obtained in discount stores through sale of professional sample kits. Patients with contact lens-associated keratitis should be questioned regarding specifics of their contact lens hygienic regimen.

Objectives: Nitric oxide (NO) plays an important role as a signal molecule as well as a cytotoxic effector molecule of the nonspecific innate immune response. The aim of this study was to examine the role played by NO during P. aeruginosa keratitis., Methods: In this study, we investigated the level of NO in BALB/c mouse eyes challenged with P. aeruginosa strains Pear1 (noninvasive/noncytotoxic), 6294 (invasive) and 6206 (cytotoxic). Following corneal challenge with P. aeruginosa, corneas were collected at 1, 8, 16, and 24 hours after infection. NO levels were measured by determining the nitrite and nitrate concentrations in the homogenates. Human corneal epithelial cells grown in tissue culture were also infected with P. aeruginosa strains and levels of NO measured., Results: In the eyes infected with P. aeruginosa strain 6294, the level of NO peaked at 16 and declined at 24-hour after challenge. For Paer1, peak NO production was also noted at 16 hours after infection. Strain 6206 produced NO at maximal level from 8 to 24 hours. Human corneal epithelial cultures infected with P. aeruginosa showed no significant production of NO, indicating that the corneal epithelium is an unlikely source of NO during infection., Conclusions: NO is produced during P. aeruginosa keratitis and may protect tissues from damage.

Purpose: To report a case of corneal perforation secondary to Acanthamoeba and fungal keratitis in a patient with a history of Intacs corneal implants., Methods: The patient's history, clinical presentation, and pathologic analysis were reviewed., Results: A 56-year-old woman with keratoconus was referred to the university eye center for a corneal perforation secondary to a chronic corneal ulcer initially diagnosed as herpes simplex keratitis. The patient had Intacs inserted in the same eye 14 months earlier, but had them removed approximately 1 month before her visit. After emergency keratoplasty, the patient's corneal tissue was sent for histopathologic examination, which showed an Acanthamoeba and fungal coinfection., Conclusions: Atypical sources of keratitis should be considered in patients with a chronic corneal ulcer and a history of Intacs corneal implants.

Purpose: Infectious keratitis after contact lens use is a known complication in cases of corneal hydrops. A case of infectious keratitis is reported in a case of keratoconus with corneal hydrops without any known predisposing factors., Methods: Infectious keratitis was diagnosed in a 58-year-old man with spontaneous onset of pain, redness, photophobia, and decreased vision. There was no history of contact lens use or any ocular allergy. Noncoagulase staphylococci were cultured from the corneal scrapings, and treatment was started with fortified antibiotics., Results: Response to treatment was noted, and the patient is awaiting keratoplasty., Conclusions: This case report highlights the occurrence of infectious keratitis in a case of keratoconus with corneal hydrops without any antecedent history of contact lens use.

Purpose: To report two cases of pseudomonas keratitis associated with daily wear of silicone hydrogel contact lenses., Methods: Medical records of two patients who developed pseudomonas keratitis while wearing silicone hydrogel lenses on a daily-wear schedule are reviewed and discussed., Results: A 13-year-old girl who wore ACUVUE Advance lenses (Johnson & Johnson Vision Care, Jacksonville, FL) 12 to 14 hours daily developed a paracentral corneal ulcer in her left eye 4 months after beginning contact lens use. Cultures were positive for Pseudomonas aeruginosa. The ulcer responded to fortified antibiotics and resolved in 10 days. Best-corrected visual acuity after resolution of the ulcer was 20/25. A 58-year-old woman with a 30-year history of rigid gas-permeable contact lens wear was refitted with O2 Optix lenses (CIBA Vision, Duluth, GA). Six months later, she had a 4.9 x 4.0 mm epithelial defect with an underlying stromal infiltrate in the right eye. Cultures were positive for P. aeruginosa. The ulcer responded to fortified antibiotics and resolved in 30 days. Best-corrected visual acuity after resolution of the ulcer was 20/30., Conclusions: Increased oxygen permeability associated with silicone hydrogel contact lenses may reduce, but does not eliminate, the risk of pseudomonas keratitis. Studies have yet to quantify the risk of keratitis associated with daily wear of these lens materials. Further study is necessary to identify the risks of complications with daily wear of silicone hydrogel lenses and to determine which factors may contribute to those risks.

Purpose: To describe the clinical features and outcomes among contact lens wearers with Fusarium keratitis., Methods: A retrospective observational review of all cases of culture-proven Fusarium keratitis among contact lens wearers from three hospitals in Hong Kong Island were included. The clinical features, hygiene habits, and clinical outcomes were reviewed., Results: Sixteen patients (17 eyes) were diagnosed with Fusarium keratitis associated with contact lens wear. One patient had bilateral involvement. Six patients had a central lesion; four had paraxial lesions; one had paraxial and peripheral lesions; and the rest had peripheral lesions. Ten (62.5%) patients reported using ReNu multipurpose cleaning solution. Most patients had poor contact lens hygiene habits. One patient required systemic antifungal treatment. No surgical intervention was required in any of the patients., Conclusions: The clinical features of Fusarium keratitis in contact lens wearers can be variable. Although fungal infection is reported rarely, clinicians should maintain a high index of suspicion for it when examining patients with contact lens-associated microbial keratitis. Education on proper contact lens care should be reinforced. Early and appropriate treatment may lead to satisfactory visual outcomes.

Purpose: To review studies of fungal keratitis related to contact lenses and determine whether the recent insurgence is a new phenomenon or an exacerbation of an ongoing trend., Methods: A review of the recent literature on contact lens-related fungal ulcers and a comparison to older studies., Results: The incidence of fungal keratitis associated with contact lenses increased from 5% in the 1980s to between 10% and 25% in the 1990s and was noted to be 44% in Florida at the turn of the century. The most recent study from Florida showed that the incidence had increased from 29% in the late 1990s to 52% in the early 2000s, even before the Fusarium keratitis epidemic in 2004 and 2005. This increase mainly represented an increase in the number related to nontherapeutic contact lenses., Conclusions: Contact lens-related fungal keratitis was relatively rare 20 years ago. However, the incidence has progressively increased since then. Contact lens-related fungal ulcers had become more common even before the recent Fusarium keratitis epidemic. This change may be related to changing contact lens care habits and younger patients being fitted with contact lenses.

Purpose: To report and define the clinical presentation, hygienic practices, treatment regimens, and visual sequelae of contact lens wearers infected with Fusarium keratitis in the New York City metropolitan area and to review the literature on Fusarium keratitis., Methods: A retrospective chart review was conducted on three patients diagnosed with Fusarium keratitis by corneal fungal culture in the New York City metropolitan area from October 2005 to February 2006. None of the patients had a history of recent ocular trauma before infection., Results: All three patients used disposable soft contact lenses and ReNu with MoistureLoc 1 month before infection. All patients experienced a unilateral stabbing pain of the affected eye after removal of the contact lens. Patients had corneal ulcers ranging from 1 to 5 mm in diameter and were all initially treated with topical antibiotics and steroids for a period between 7 and 52 days. Antifungal treatment was eventually prescribed to all patients, with topical natamycin 5% every hour being the most common. One patient required corneal transplantation, and the other two patients recovered visual acuity comparable to their baseline acuity., Conclusions: A delay in diagnosis and prolonged treatment delay of Fusarium keratitis is associated with significant comorbidity. Physicians must have a higher index of suspicion for fungal keratitis in contact lens wearers to facilitate in early diagnosis and treatment.

Purpose: To identify microbiologic characteristics of infectious keratitis associated with contact lenses., Methods: The authors retrospectively examined the microorganism isolated from patients with microbial corneal ulcer associated with contact lenses during a 5-year period. Herpetic and other viral infections were excluded from this study. Patient age, sex, type of contact lens, and isolated organisms were collected from medical records., Results: Sixty-seven eyes of 66 patients (54.5%) who possibly had contact lens-induced infectious keratitis were reviewed. Cultures of corneal scrapings or eye discharge were positive in 30 (44.8%) of 67 eyes. A total of 35 strains of bacteria were detected, among which there were 29 (82.9%) gram-positive bacteria, two (5.7%) gram-negative bacteria, three (8.6%) fungi, and one (2.9%) species of Acanthamoeba. The most common type of contact lens was a conventional soft contact lens (25 eyes, including extended wear in seven eyes), whereas hard contact lenses, including rigid gas-permeable contact lenses, were worn in 19 eyes. In addition, frequent-replacement lenses were used in 17 eyes, whereas weekly lenses and daily lenses were used for three eyes each. The largest age group was the 20s for all types of lenses., Conclusions: The results of isolation and culture are essential for improving the cure rate, especially for patients who have severe corneal ulcers.

Purpose: To identify microbiologic characteristics of infectious keratitis and predisposing factors., Methods: The microorganisms isolated from patients with infectious corneal ulcers during the 5 years between January 1999 and December 2003 were retrospectively examined. Herpetic and other viral infections were excluded from this study. Patient age, sex, risk factors, and isolated organisms were collected., Results: In 123 eyes of 122 patients, organisms were isolated from 72 (58.5%) eyes. In total, 99 different organisms were isolated. Among these, 77 (77.8%) were gram-positive bacteria; 18 (18.2%) were gram-negative bacteria; six (6.1%) were fungi; and one (1.0%) was acanthamoeba. Contact lens wear was the main risk factor (54.5%), and ocular surface disease and previous ocular surgery were present in 20.5% and 13.1% of cases, respectively. Posttreatment visual acuity was significantly improved by pretreatment in culture-positive groups treated according to the antibiotic susceptibilities (Wilcoxon t test, P<0.01)., Conclusions: The results are changing to those reported by other countries and generations. Contact lens wear is the most important risk factor in Japan. The results of isolation and culture are essential for improving the cure rate.

Purpose: To report a case of culture-positive Staphylococcus aureus keratitis associated with continuous wear of lotrafilcon A lenses., Methods: The case report of a patient who developed microbial keratitis while wearing lotrafilcon A contact lenses is presented., Results: A 41-year-old white man had worn polymacon contact lenses successfully for at least 10 years. He habitually replaced the lenses every 1 to 2 years and frequently wore them continuously for up to 3 months. He was refitted with silicone hydrogel lenses and was advised to remove and replace the lenses monthly. Approximately 18 months later, he developed a midperipheral, culture-positive S. aureus ulcer in his right eye. He was treated with fortified cefazolin and gentamicin for 2 weeks, followed by ciprofloxacin for 2 weeks. The ulcer resolved completely. The patient's final visual acuity was 20/20 in the affected eye., Conclusions: The increased oxygen permeability of silicone hydrogel contact lens materials may reduce the risk of hypoxic complications of continuous contact lens wear. As this case shows, however, even patients who have continuously worn lenses with very low oxygen permeability without incident can develop microbial keratitis when wearing silicone hydrogel lenses. Contact lens practitioners should inform patients of the potential risks of continuous wear and of factors that may increase those risks.

Purpose: To report a case that suggests that factors associated with daily disposable contact lenses contribute to the risk of developing infectious keratitis., Methods: A case of a culture-positive Pseudomonas corneal ulcer in a compliant daily disposable contact lens wearer is presented., Results: The case involves a 35-year-old woman with a culture-positive Pseudomonas corneal ulcer that was treated successfully with topical antibiotics. The patient wore daily disposable contact lenses on a part-time basis and was fully compliant with the instructions for use., Conclusions: Compliance and wearing time were not causal in this episode of infectious keratitis, but factors related to the lens might have been.

Purpose: To report a case of a corneal ulcer in a patient who wore orthokeratology contact lenses during the day., Methods: Case report., Results: A 16-year-old girl who underwent orthokeratology treatment developed a corneal ulcer in her right eye. The refractive status of the affected eye was -5.75 -1.75 x 180, and the best-corrected visual acuity was 20/40. Corneal topography showed the temporal upper dislocation of a central flattened zone in the right eye. The patient had worn orthokeratology contact lenses during the day for more than 4 years. Her ulcer became worse after treatment with tobramycin and gentamicin for 1 day. After treatment with ciprofloxacin, the ulcer healed, and visual acuity returned to 20/20 with spectacle correction. Cultures of the cornea, contact lens, and lens solution all grew Burkholderia cepacia, Pseudomonas putida, and Pseudomonas aeruginosa., Conclusions: Improper fitting of lenses and contamination of lenses or solutions in orthokeratology therapy are risk factors for a corneal ulcer, even when patients wear orthokeratology lenses only during the day.

Purpose: To report the development of severe ulcerative keratitis in an adolescent, shortly after initiating corneal refractive therapy., Methods: A teenager developed severe ulcerative keratitis shortly after being fitted with reverse-geometry contact lenses. The contact lenses were worn daily and only one night before the occurrence of severe ulcerative keratitis. Pseudomonas aeruginosa was identified as the causative organism., Results: The patient was treated with intensive, fortified antibiotics with gradual resolution of the corneal ulcer, leaving a permanent central stromal scar., Conclusions: Corneal refractive therapy contact lenses can cause severe bacterial keratitis even after a short wearing time. Significant caution should be used before prescribing corneal refractive therapy lenses, and informed consent should include potential sight-threatening infectious keratitis.

Purpose: Despite growing evidence for clinical efficacy of orthokeratology (OK) for the temporary reduction of myopic refractive error, there has been an increasing number of reports of microbial keratitis (MK) in association with overnight wear of OK lenses. This article analyzes the first 50 cases of MK reported in overnight OK, in order to define the spectrum of the disease and to identify possible risk factors., Methods: All reported cases of presumed MK in overnight OK from 2001 onwards were included in the analysis. Demographic data of patients affected and lenses worn, and details of the disease process and possible risk factors were extracted from these reports., Results: Most cases of MK in OK were reported from East Asia (80%) and most affected patients were Asian (88%). The peak age range was from 9 to 15 years (61%). Although Pseudomonas aeruginosa was the predominant organism implicated in this series of cases (52%), an alarmingly high frequency of Acanthamoeba infection (30%) was found. Inappropriate lens care procedures, patient noncompliance with practitioner instructions, and persisting in lens wear despite discomfort emerged as potential risk factors., Conclusions: The high frequency of MK in overnight OK in young Asian patients is likely to reflect the demographics of the OK lens-wearing population. The high frequency of Acanthamoeba infection strongly suggests that tap water rinsing should be eliminated from the lens care regimen for overnight OK. This study does not reveal the absolute incidence or relative risk of MK in overnight OK, and it is therefore premature to ascribe increased risk to this lens-wearing modality compared with other contact lens modalities.

Objectives: To report the development of corneal ulcers in two children wearing Paragon Corneal Refractive Therapy (CRT) lenses., Methods: Two case reports of children who developed corneal ulcers when fit with Paragon CRT contact lenses, which were worn nightly, are discussed. Each patient presented with a bacterial corneal ulcer after wearing CRT contact lenses for less than 6 months. In the first patient, Pseudomonas aeruginosa was identified as the causative organism. In the second patient, Haemophilus influenza was cultured from the ulcer., Results: Both patients were treated with intensive, fortified antibiotics with rapid resolution of the corneal ulcers and preservation of vision. No surgical intervention was required., Conclusions: Paragon CRT lenses have been approved for use in patients of all ages. When used in children, these lenses may present unique problems. The absolute incidence of bacterial corneal ulcers in patients with CRT lenses are unknown. Severe caution should be used before prescribing CRT lenses for children and informed consent should include potential sight-threatening corneal ulcers.

Purpose: This case series presents the first documented cases of infectious ulcers associated with overnight orthokeratology in North America and other less serious complications associated with overnight corneal reshaping., Case Reports: Five cases of adverse corneal events associated with corneal refractive therapy are described: two cases of microbial keratitis, one case of infiltrates, one case of toxic keratitis, and one corneal abrasion., Conclusions: Corneal compromise and poor compliance can cause adverse events with corneal reshaping. The need for ongoing patient education is important not only for pediatric contact lens patients, but also for adults.

Purpose: To report a case of Pseudomonas aeruginosa culture-positive microbial keratitis in a patient wearing continuous-wear silicone hydrogel soft contact lenses., Methods: A 23-year-old white woman in good health had been wearing silicone hydrogel (lotrafilcon A) soft contact lenses continuously for 26 days when she was examined for a corneal ulcer in her left eye. She had given a history of water jet skiing and diving while wearing her contact lenses. Scrapings of the corneal ulcer were positive for P. aeruginosa, and the patient was treated with fortified topical cefazolin and gentamicin for 1 week and subsequently with topical ciprofloxacin for 2 weeks., Results: The microbial keratitis resolved with successful treatment. However, the patient had a residual visual deficit secondary to stromal scarring., Conclusions: The recently introduced continuous-wear silicone hydrogel soft contact lenses, with their hyper oxygen permeability (Dk), have been shown to overcome hypoxia-associated complications and to have less P. aeruginosa binding to the corneal epithelium. Our case shows that sight-threatening microbial keratitis can still occur even with silicone hydrogel soft contact lenses. Contact lens practitioners should educate patients on the risk of sight-threatening microbial keratitis, the need for patient compliance, and prompt assessment of contact lens-related complaints.

Purpose: To determine the clinical microbiological characteristics of corneal ulcers in contact lens wearers., Methods: A retrospective study of 23 patients admitted to our department with contact lens-related corneal ulcers during a 43-month period. Detailed demographic data, the type of contact lens, duration of lens wear, and wearing schedule were derived from a self-administered questionnaire. The severity of the ulcer; cultures of corneal scrapings, storage solutions, and contact lenses; treatment; and final outcome were evaluated., Results: Of the 86 cases of ulcerative keratitis admitted during the study period, 23 (26.74%) were attributed to contact lens use. Most patients were young women from urban areas. All of them were using soft contact lenses for 3 days to 20 years. Five patients used daily-wear lenses as extended-wear lenses. Most ulcers (47.82%) were mild; 30.43% were moderate; and 21.47% were severe. Corneal scrapings for cultures were obtained in 15 of the cases and were positive in 10 (43.47%) of them, whereas in 33.33% of the culture-positive storage solutions and in 66.67% of the culture-positive contact lenses, corneal scrapings were negative. Pseudomonas aeruginosa was the most frequent isolated pathogen (60%). The final visual acuity was 20/40 or better in 60.87% of the cases., Conclusions: Contact lens use is an important risk factor for the development of ulcerative keratitis, with P. aeruginosa remaining the predominant pathogen. It seems important to culture contact lenses and contact lens storage solutions, in addition to the corneal scrapings, and the role of initial therapy for the corneal ulcers remains important.

Background: Pseudomonas keratitis can result in the breakdown of collagen with subsequent corneal melting and perforation. The use of antimetalloproteinases may help to stabilize melting and prevent imminent perforation of the cornea. The use of topical protease inhibitors and neutrophil inhibitors is of limited value. Tetracyclines, however, have been shown to have anticollagenolytic activity and inhibit metalloproteinases, and they may suppress connective tissue breakdown., Purpose: To establish the stabilization of corneal melting in cases of Pseudomonas keratitis., Methods: Two young patients with severe contact lens-associated Pseudomonas keratitis and corneal melting were treated with oral doxycycline and standard topical treatment., Results: Corneal melting was stabilized in each patient, and perforation was avoided., Conclusions: Tetracyclines have an anticollagenolytic action in addition to their antimicrobial activity. The use of doxycycline as an adjunctive therapy in the management of Pseudomonas corneal melting may help to stabilize corneal breakdown and prevent subsequent perforation.

Purpose: To report a case of unusual ulcer morphology in orthokeratology-related corneal ulcer., Methods: A single observational case report of a 14-year-old Chinese female myope with a 1.5-month experience wearing overnight B.E. orthokeratology (Capricornia) lenses and presenting with a right stellate-shaped central cornea abscess. Cornea scrapings for Gram stains, culture, and antibiotic sensitivity were performed. The patient was prescribed hourly fortified cefazolin and gentamicin drops., Results: Pseudomonas aeruginosa grew on blood and chocolate agar cultures. The ulcer was successfully treated with antibiotics and reepithelialized over 5 days. There was a residual central corneal scar. The refraction changed from -4.25 sphere OD and -1.75 -1.75 x160 OS to -3.50 -1.50 x160 OD and -1.50 -1.75 x165, giving a visual acuity of 20/ 25 OD and 20/20 OS., Conclusions: A flatter fit of orthokeratology lenses may be associated with unusual cornea ulcer morphology.

Purpose: To report two cases of infectious keratitis associated with the use of daily disposable soft contact lenses., Method: Two case reports of individuals who developed infectious keratitis while wearing daily disposable soft contact lenses are presented., Results: The first case is that of a 34-year-old woman who had been using daily disposable soft contact lenses for 18 months before she developed a corneal ulcer in her left eye. The cultures grew Pseudomonas aeruginosa, and she was treated successfully with fortified topical antibiotics. The second case describes a 30-year-old woman who had been using conventional soft contact lenses for 5 years before switching to daily disposable soft contact lenses 3 months before presentation. She was found to have a corneal ulcer in her left eye that grew Staphylococcus aureus on cultures, and she responded to topical antibiotic treatment., Conclusions: Although daily disposable soft contact lenses theoretically have a lower risk of infectious keratitis compared with other lens wear regimens, reports have shown that at least some risk remains. These lenses should be prescribed and used with great care to minimize contact lens-related infectious keratitis.

Purpose: To present a case of bilateral methicillin-resistant Staphylococcus aureus (MRSA) keratitis after photorefractive keratectomy (PRK)., Methods: Retrospective chart review. RESULTS A 26-year-old female internal medicine resident underwent an uneventful bilateral PRK. After the procedure, the patient was fit with a bandage contact lens and was prescribed tobramycin 0.3%, fluorometholone 0.1%, and diclofenac sodium 0.1% four times per day. Postoperatively, corneal ulcers were noted in each eye, and the patient was referred for a consultation. Gram stain showed gram-positive cocci. The patient immediately started using vancomycin, 35 mg/mL every half hour, and ofloxacin 0.3% every hour around the clock. Forty-eight hours later, corneal and lid cultures were positive for MRSA. Three months after the infection, there was approximately 40% corneal thinning in the right eye and 10% thinning in the area of the corneal ulceration of the left eye. The patient is awaiting corneal transplantation of the right eye., Conclusions: To our knowledge, this represents the first reported case of bilateral MRSA keratitis after PRK. Methicillin-resistant S. aureus is a potentially serious infectious agent after PRK and may be associated with exposure to a hospital setting. For patients who have had extensive exposure to a hospital environment and are undergoing ocular surgery, we recommend prophylaxis against MRSA. To treat a possible MRSA keratitis, we suggest starting a fourth-generation topical fluoroquinolone every 30 minutes, alternating it with vancomycin 50 mg/mL every 30 minutes, and discontinuing steroid use. A high degree of suspicion coupled with rapid and appropriate treatment may result in improved visual recovery.

Since their introduction, the most significant complication of wearing soft contact lenses has been the development of vision-threatening microbial keratitis. In lens-wearing corneas, microbial infection is thought to develop in the absence of overt injury, leading to the hypothesis that microbe interactions with the corneal epithelium are critical to the pathogenesis of this disease. Thus, we have focused our research efforts on understanding microbial virulence mechanisms aimed at corneal epithelial cells and the innate defenses that normally protect them using the gram-negative bacterium Pseudomonas aeruginosa as a model organism. This report summarizes those results and explores their relevance to understanding contact lens-related infections.

Purpose: This analysis reports on risk factors for corneal infiltrative events from a 1-year, randomized clinical trial of lotrafilcon A lenses., Methods: Six hundred fifty-eight subjects randomized to lotrafilcon A lenses were observed in a 1-year clinical trial in the United States. Risk factors gathered at baseline were analyzed to determine their association with corneal infiltrative events., Results: Factors examined but not found to be associated with events were male sex, history of extended or daily lens wear, refractive error, neovascularization, or assessment of lens fit. Significant factors included subject age 18 to 29 years, smoking, smoking and young age combined, history of corneal scar, contact lens acute red eye (CLARE), and corneal infiltrates., Conclusion: Risk factors for corneal infiltrative events with silicone hydrogel lenses worn for 30 nights of continuous wear have been identified. Wearers with a history of inflammatory events such as contact lens peripheral ulcer or CLARE should consider 30-night continuous wear with these lenses. Careful counseling of wearers who smoke is advised.

Purpose: Microbial keratitis is the only sight-threatening adverse event that occurs with contact lens wear. This article gives a preliminary estimation of the incidence of microbial keratitis and vision loss with continuous-wear contact lenses made from highly oxygen permeable (Dk) materials., Methods: The most up-to-date data available on microbial keratitis and vision loss are collected from a range of sources including industry, private practice, and publications and is reviewed., Results: There have been 16 cases of microbial keratitis with high-Dk silicone hydrogel lenses. Of the 13 where data are available, none have lost two or more lines of best-corrected visual acuity (BCVA)., Conclusion: First approximation indicates that the incidence of microbial keratitis with high-Dk silicone hydrogel lenses may be lower than the incidence with low-Dk soft lenses during extended wear. The rate of loss of more than two lines of BCVA is low in patients that develop microbial keratitis with low- and high-Dk soft lenses.