Endophthalmitis associated with microbial keratitis

Validation of the C-DU(KE) Calculator as a Predictor of Outcomes in Patients Enrolled in Steroids for Corneal Ulcer and Mycotic Ulcer Treatment Trials

PURPOSE

The aim of this study was to validate the C-DU(KE) calculator as a predictor of treatment outcomes on a data set derived from patients with culture-positive ulcers.

METHODS

C-DU(KE) criteria were compiled from a data set consisting of 1063 cases of infectious keratitis from the Steroids for Corneal Ulcer Trial (SCUT) and Mycotic Ulcer Treatment Trial (MUTT) studies. These criteria include corticosteroid use after symptoms, visual acuity, ulcer area, fungal etiology, and elapsed time to organism-sensitive therapy. Univariate analysis was performed followed by multivariable logistic regressions on culture-exclusive and culture-inclusive models to assess for associations between the variables and outcome. The predictive probability of treatment failure, defined as the need for surgical intervention, was calculated for each study participant. Discrimination was assessed using the area under the curve for each model.

RESULTS

Overall, 17.9% of SCUT/MUTT participants required surgical intervention. Univariate analysis showed that decreased visual acuity, larger ulcer area, and fungal etiology had a significant association with failed medical management. The other 2 criteria did not. In the culture-exclusive model, 2 of 3 criteria, decreased vision [odds ratio (OR) = 3.13, P < 0.001] and increased ulcer area (OR = 1.03, P < 0.001), affected outcomes. In the culture-inclusive model, 3 of 5 criteria, decreased vision (OR = 4.9, P < 0.001), ulcer area (OR = 1.02, P < 0.001), and fungal etiology (OR = 9.8, P < 0.001), affected results. The area under the curves were 0.784 for the culture-exclusive model and 0.846 for the culture-inclusive model which were comparable to the original study.

CONCLUSIONS

The C-DU(KE) calculator is generalizable to a study population from large international studies primarily taking place in India. These results support its use as a risk stratification tool assisting ophthalmologists in patient management.

Consensus and controversies in the science of endophthalmitis management: Basic research and clinical perspectives

Infectious endophthalmitis is a severe intraocular infection caused by bacteria, or less commonly by fungi. It can occur after penetrating eye procedures, trauma, or the spread of infection from contiguous structures or via emboli from distant organs. Because of the time-critical nature of the treatment, endophthalmitis is treated with the clinical diagnosis and modified by the microbiological report of the intraocular contents. The current strategy for managing endophthalmitis relies on pre-clinical literature, case series, and one large multi-center randomized clinical trial on post-cataract surgery endophthalmitis. Culture-susceptibility of the microorganisms from undiluted vitreous guides the definitive treatment in non-responsive cases. Strategies to reduce the incidence of endophthalmitis after penetrating eye procedures have been developed concurrently with refined means of treatment. Despite these advances, outcomes remain poor for many patients. Although consensus articles have been published on managing endophthalmitis, treatment patterns vary, and controversies remain. These include (1) the use of newer methods for early and precise microbiological diagnosis; (2) the choice of intravitreal antibiotics; (3) the need for systemic therapy; (4) early and complete vitrectomy. Here, we review the current consensus and address controversies in diagnosing and managing endophthalmitis. This review is intended to familiarize physicians and ophthalmologists with different aspects of endophthalmitis management to make informed decisions.

Clinical comparative analysis of culture-proven bacterial keratitis according to prior topical steroid use: a retrospective study in a tertiary referral center of South Korea

This study analyzed the clinical characteristics of patients exposed to topical steroids before bacterial keratitis diagnosis (the prior topical steroid use, PS group), and compared these with those of the non-exposed group (the no prior topical steroid use, NPS group). We retrospectively analyzed 194 patients (PS, 34; NPS, 160) with culture-proven bacterial keratitis between 2007 and 2016. The microbiological profiles, epidemiology, predisposing factors, clinical characteristics, and treatment outcomes of PS and NPS were compared, and the risk factors for surgical intervention were evaluated. Pseudomonas spp. and Staphylococcus spp. were the most common isolates in PS and NPS, respectively, and no significant difference in the strain distribution between the two groups were observed. Significant differences were observed between PS and NPS for previous ocular surface disease (41.2%: 23.8%), initial BCVA < 0.1 (70.6%: 49.4%), epithelial defect size ≥ 5 mm2 (64.7%: 41.2%), epithelial healing time > 14 days (55.9%: 37.3%), and surgical intervention (23.5%: 8.8%). Prior topical steroid use, strong steroid use, and long-term steroid use groups were included in significant risk factors for surgical intervention. Previous exposure to topical steroids before the diagnosis of bacterial keratitis was associated with a worse initial clinical presentation and treatment outcomes. Additional multicenter studies should be conducted in the future.

Exogenous Endophthalmitis

PURPOSE

Exogenous endophthalmitis (ExE) results from microbial infection as a complication of ocular surgery, penetrating ocular trauma, and intraocular foreign bodies. We herein review the classification of ExE, etiological agents, differential diagnosis and therapeutic challenges.

METHODS

Narrative Literature Review.

RESULTS

Identification of the causative agent through ocular fluid analysis is central in the diagnostic work-up of ExE. Prompt intravitreal antimicrobial therapy is key to successful management of ExE and vitrectomy is essential in severe cases. In culture-negative cases, and in the presence of specific features, a diagnosis of sterile intraocular inflammation or toxic syndrome should be suspected.

CONCLUSION

Strict adherence to treatment guidelines may improve outcomes of ExE, however the ultimate prognosis, especially in severe cases, may depend more on the virulence of the causative organism and associated ocular complications. Accurate differential diagnosis and effective treatment are crucial elements in the management and prognosis of non-infectious masquerades of ExE.

Bacterial Keratitis: Clinical Features, Causative Organisms, and Outcome During a 13-year Study Period

PURPOSE

This study aimed to review clinical features, causative organisms, complications, and outcome of bacterial keratitis cases at a tertiary eye hospital.

METHODS

A retrospective study was conducted on clinically diagnosed bacterial keratitis cases from 2007 to 2019. Poor outcome was flagged if any of the following was identified: final visual acuity (VA) worse than 20/200, decrease in VA (1 line or worse compared with presenting VA), corneal perforation, endophthalmitis, failed graft, or cases requiring enucleation or evisceration.

RESULTS

The study included 263 cases of bacterial keratitis with 169 cases (64.3%) of culture-positive bacterial keratitis. Gram-positive bacteria were found to be the causative organism in 106 cases (62.8%). The most common types were coagulase-negative staphylococci (23.1%) and Pseudomonas (23.1%). Culture-positive bacterial keratitis was associated with the development of anterior chamber reaction (≥1+) on multivariate analysis [adjusted odds ratio (OR): 3.03, confidence interval (CI): 1.23-7.45, P = 0.016]. The complications that occurred in the current cohort included visually significant scar (64.7%), perforation (10.8%), cataract (8.8%), nonhealing epithelial defects (8.0%), corneal neovascularization (4.9%), endophthalmitis (4.6%), and hypotony (1.5%). On multivariate analysis, diabetes mellitus (adjusted OR: 3.51, CI: 1.59-7.76, P = 0.002), poor presenting best-corrected VA (adjusted OR: 3.95, CI 1.96-7.96, P < 0.001), and positive cultures (adjusted OR: 2.36, CI: 1.11-5.00, P = 0.025) were associated with poor outcome.

CONCLUSIONS

Culture-negative keratitis had less severe infection and better outcomes when compared to culture-positive bacterial keratitis. Factors associated with poor outcome included diabetes, poor presenting VA, and positive cultures.

Urgent unmet needs in the care of bacterial keratitis: An evidence-based synthesis

Bacterial corneal infections, or bacterial keratitis (BK), are ophthalmic emergencies that frequently lead to irreversible visual impairment. Though increasingly recognized as a major cause of global blindness, modern paradigms of evidence-based care in BK have remained at a diagnostic and therapeutic impasse for over half a century. Current standards of management - based on the collection of corneal cultures and the application of broad-spectrum topical antibiotics - are beset by important yet widely underrecognized limitations, including approximately 30% of all patients who will develop moderate to severe vision loss in the affected eye. Though recent advances have involved a more clearly defined role for adjunctive topical corticosteroids, and novel therapies such as corneal crosslinking, overall progress to improve patient and population-based outcomes remains incommensurate to the chronic morbidity caused by this disease. Recognizing that the care of BK is guided by the clinical axiom, "time equals vision", this chapter offers an evidence-based synthesis for the clinical management of these infections, underscoring critical unmet needs in disease prevention, diagnosis, and treatment.

C-DU(KE) Calculator: A Clinical Tool for Risk Stratification in Infectious Keratitis

PURPOSE

The aim of this study was to identify characteristics of infectious keratitis predictive of poor outcome to develop a web-based predictive calculator.

METHOD

A retrospective chart review was performed at the Duke Eye Center. Two hundred fifteen adult patients with culture-proven infectious keratitis presenting between January 1, 2016, and December 31, 2020, were separated into a derivation set (136 patients, 53 positives; 83 controls) and a temporal validation set (79 patients, 26 positives; 53 controls). The poor outcome group consisted of patients requiring penetrating keratoplasty for visually significant scarring, penetrating keratoplasty for ulcer progression, or evisceration/enucleation for endophthalmitis. Univariable analysis was performed followed by stepwise multivariable logistic regression to obtain a predictive model in the derivation data set. Culture-naïve and postculture models were constructed. Discrimination and calibration were assessed using the area under the curve (AUC) and calibration plots, respectively.

RESULTS

The culture-naïve model consisted of corticosteroid drop use postsymptom onset [Odds Ratio (OR) = 2.3, P = 0.054], decreased vision (OR = 2.4, P = 0.001), and increased ulcer area (OR = 1.017, P = 0.017). The postculture model additionally included fungal keratitis (OR = 5.4, P = 0.006) and elapsed time from symptoms to organism-sensitive therapy (OR = 1.027, P = 0.014). The models were summarized by the acronym C-DU(KE). The AUCs for the culture-naïve model were 0.794 in the derivation set and 0.850 in the validation set. The AUCs for the postculture model were 0.898 in the derivation set and 0.946 in the validation set. Calibration plots indicated goodness of fit in the data sets for both models. The calculator was deployed under the URL: https://duke-eye-calculator.shinyapps.io/Corneal_Ulcers/ .

CONCLUSIONS

The C-DU(KE) calculator permits a data-driven prediction of outcome in infectious keratitis that can supplement clinical judgment.

Pars plana vitrectomy and therapeutic keratoplasty in endophthalmitis and infectious keratitis

PURPOSE

To describe the anatomical and functional outcomes of patients with infectious keratitis (IK) and secondary endophthalmitis who underwent penetrating keratoplasty (PK) after pars plana vitrectomy (PPV) assisted by temporary keratoprosthesis (TKP).

METHODS

An observational retrospective case series was performed. Data were collected from January 2013 to July 2020. Patients over 18 years old with a clinical and microbiological diagnosis of IK, and clinical, ultrasonographic, and or microbiological diagnosis of endophthalmitis were included. Anatomical success was defined as infection resolution with preservation of the ocular globe integrity. No change or improvement of best-corrected visual acuity (VA) at the last follow-up was considered as a functional success.

RESULTS

A total of 32 eyes of 32 patients were analyzed. The anatomic success was obtained in 87.5% eyes in which the infection was eradicated. The 63% patients maintained or improved their best-corrected VA, 37.5% ended up with hand motion VA.

CONCLUSIONS

Our results suggest that PPV assisted by TKP followed by PKP can be a good approach for treating patients with endophthalmitis secondary to IK while allowing further visual improvement after an optical PK. Further prospective studies need to be done to evaluate final visual rehabilitation of these patients.

Highlighting the Microbial Contamination of the Dropper Tip and Cap of In-Use Eye Drops, the Associated Contributory Factors, and the Risk of Infection: A Past-30-Years Literature Review

The sterility of eye drop content is a primary concern from manufacturing until opening, as well as during handling by end users, while microbial contamination of the dropper tip and cap are often disregarded. The contamination of these sites during drug administration represents a risk of microbial transmission and ocular infection. In this review, we aim to assess microbial contamination of the dropper tip and cap of in-use eye drops, the associated contributory factors, and the risk of infection. We conducted a literature search of the MEDLINE, PubMed, and Cochrane Central databases. A total of 31 out of 1503 studies were selected. All the studies conducted in different settings that documented microbiologically contaminated in-use eye drops were included. Our review showed that microbial contamination of the dropper tip and cap of in-use eye drops ranged from 7.7 to 100% of the total contaminated tested samples. Documented contributory factors were conflicting across the literature. Studies investigating the association between eye infection and microbial contamination of the dropper tip and cap were scarce. New technologies offer a promising potential for securing the long-term sterility of eye drop content, tips, and caps, which could benefit from more research and well-defined study protocols under real-life scenarios.

Combined Therapeutic Penetrating Keratoplasty and Pars Plana Vitrectomy for the Treatment of Infectious Keratitis Endophthalmitis: Mexican Endophthalmitis Study Group Protocol 4

PURPOSE

The purpose of this study was to assess the role of combined surgical treatment of therapeutic penetrating keratoplasty and pars plana vitrectomy in the anatomical and functional outcome of infectious keratitis endophthalmitis.

METHODS

This study reviewed the medical records of 4 participating centers in the United States and Mexico. This study included patients with a clinical diagnosis of infectious keratitis endophthalmitis who had been treated with an early therapeutic penetrating keratoplasty and pars plana vitrectomy as the main treatment for endophthalmitis. From each medical record, the study retrieved demographic data, relevant medical and drug history, baseline clinical manifestation of endophthalmitis, best-corrected visual acuity, and the need for enucleation/evisceration for the control of the infection or any other reason through the follow-up.

RESULTS

The study included 48 patients (50.15 ± 20.6 years). The mean follow-up time was 13 ± 0.5 months. The mean best-corrected visual acuity at baseline was 2.1 ± 0.25 logarithm of the minimum angle of resolution. At month 12 was 2.09 ± 0.61 logarithm of the minimum angle of resolution ( P = 0.9). The overall prevalence of enucleation/evisceration was 8.3% (95% confidence interval: 2.32%-19.98%). The prevalence of a vision of no-light perception was 20.8% (95% confidence interval: 2.32%-19.98%).

CONCLUSIONS

Combined surgery for severe cases of infectious keratitis endophthalmitis eradicates the infection in most cases, while significantly improving the overall outcomes.

Lacrimal Duct Obstruction and Infection Associated with Non-Traumatic Corneal Perforation: A Case Series

Purpose

To report a case series of lacrimal duct obstruction and infection associated with non-traumatic corneal perforation.

Case Series

This study included 6 eyes in 6 patients with non-traumatic corneal perforation treated between April 2019 and March 2021. All 6 cases were associated with lacrimal duct obstruction and infection. Purulent discharge caused by lacrimal duct infection was observed in all 6 patients (100%). However, three of the 6 patients (50%) did not show purulent discharge at initial examination and lacrimal duct obstruction was therefore not initially recognized. Dry eye was observed in five of the 6 patients (83%) and may have caused corneal deterioration, increasing susceptibility to perforation. Further, dry eye masks symptoms of lacrimal duct obstruction and infections, such as epiphora and regurgitation of purulent discharge, making the association with lacrimal duct obstruction and infection difficult to determine. All patients were treated for both corneal perforation and lacrimal duct disease, and conditions improved, with no recurrence of either corneal perforation or lacrimal duct disease.

Conclusion

In patients with a combination of lacrimal duct disease and corneal perforation, treatment of both diseases resulted in stabilization of patient condition. Dry eyes may mask symptoms of lacrimal duct diseases, such as epiphora and purulent discharge, and lacrimal duct disease may thus be underdiagnosed.

Risk Factors Leading to Enucleation or Evisceration in Infectious Endophthalmitis

Endophthalmitis treatment consists of intravitreal antibiotics injections and, in selected circumstances, pars plana vitrectomy. However, severe or refractory cases may require an enucleation or evisceration (ENEV). Our study seeks to identify risk factors leading to enucleation or evisceration in patients with infectious endophthalmitis. A retrospective chart review of subjects with a clinical diagnosis of infectious endophthalmitis was undertaken. The affected eyes were stratified into groups: those that underwent ENEV and those in which the eyeball was preserved (EP). The groups were compared using statistical analyses. In total, 69 eyes diagnosed with infectious endophthalmitis were included in the study. There was a higher frequency of exogenous infectious endophthalmitis in the ENEV group versus the EP group. Postsurgical infectious endophthalmitis was lower in the ENEV than in the EP group. A visual acuity of no light perception was more common in the ENEV compared to the EP group. Panophthalmitis was more frequent in the ENEV versus the EP group. Our findings suggest that eyes with endophthalmitis presenting with a visual acuity of no light perception, panophthalmitis, or exogenous etiology have a higher risk of requiring ENEV. In addition, eyes with a postsurgical etiology may be at a lower risk of requiring ENEV.

Risk factors and microbiological characteristics: from bacterial keratitis with hypopyon to keratitis-related endophthalmitis

PURPOSE

To compare the clinical and microbiological characteristics in patients with bacterial keratitis with hypopyon (BKH), bacterial keratitis-related endophthalmitis (BKE), and bacterial endophthalmitis without keratitis (BE).

METHODS

Data from all inpatients who were clinically diagnosed with BKH, BKE, and BE from 2018 to 2020 were collected retrospectively. The demographics, predisposing risk factors, clinical characteristics, microbiological profiles, and antibiotic susceptibility of the patients were evaluated.

RESULTS

Approximately 9.46% (28/296) of eyes with BKH progressed to endophthalmitis. The hypopyon (OR = 5.35, 95% CI: 2.17-7.08) and corneal perforation (OR = 2.47, 95% CI: 1.04-4.86) were significantly related to the development of BKE. The odds ratios for hypopyon of less than 1 mm, 1-3 mm, and greater than 3 mm were 1, 2.09 (95% CI: 1.17-3.15), and 4.12 (95% CI:2.59-5.68), respectively. The predominant causative pathogen was Staphylococcus epidermidis (36.43%, 38.89%), followed by Streptococci (14.73%, 16.67%), Staphylococcus aureus (8.53%, 7.79%), and Pseudomonas aeruginosa (9.30%, 7.14%) in eyes with BKH and BE. However, the main pathogens were Pseudomonas aeruginosa (37.50%) and Staphylococcus aureus (31.25%) in eyes with BKE. In the BKH, BKE, and BE groups, almost 100% of Staphylococcus aureus isolates were sensitive to vancomycin (97.70%, 100%, 95.56%), about a half were sensitive to fluoroquinolones (51.85%, 39.90%, 62.34%), and approximately 30% were sensitive to trimethoprim/sulfa (27.77%, 21.56%, 33.56%) and cefazolin (41.47%, 20.31%, 38.81%). The susceptibility of Pseudomonas aeruginosa to fluoroquinolones antibiotics was 55.75%, 66.67%, and 62.58%, respectively, in the three groups.

CONCLUSIONS

The height of hypopyon and corneal perforation are risk factors for progression to endophthalmitis in eyes with bacterial keratitis. When Staphylococcus aureus and Pseudomonas aeruginosa are identified, vigilance is required for advanced endophthalmitis.

Epidemiology of keratitis/scleritis-related endophthalmitis in a university hospital in Thailand

To demonstrate the demographics, associated factors, clinical presentations, microbiology, management, visual outcome and complications of keratitis/scleritis-related endophthalmitis (KSE). A retrospective chart of all endophthalmitis patients diagnosed between September 2001 and August 2011 was reviewed. Only endophthalmitis cases with previous corneal or scleral infection were included in the study. The patients were followed until losing vision or eyeball, becoming phthisis, or the end of 2018. Eighty-seven patients with KSE were identified, all unilateral. The mean age was 56.4 ± 21.4 years. There was a slight male predilection (55 patients, 63.2%). The mean follow-up time was 50 ± 149 weeks. The causative pathogens were identified in 35 patients (40.2%), with the highest frequency being bacteria. The most common bacterium was Pseudomonas aeruginosa (n = 13), and the most common fungus was Aspergillus sp. (n = 5). Fifteen patients achieved (17.2%) final visual acuity (VA) of hand motion or better after treatment. Eyeball removal was performed in 61 (70.1%) patients. From multivariate analysis, the only prognostic factor for poor final VA (worse than hand motion, HM) was poor VA (worse than HM) at the initial visit (relative risk 1.97, 95% confidence interval 1.15–3.36, p = 0.013). KSE is uncommon but has a devastating outcome. We found that the patient’s initial VA was the only predictor for their final vision. P. aeruginosa was the most common identifiable organism in this study. However, several fungal infections were recognised. These findings should raise awareness for treatment of KSE in the tropics.

The Role of Systemic Antimicrobials in the Treatment of Endophthalmitis: A Review and an International Perspective

Background

The optimal management of patients with endophthalmitis is challenging and includes both intravitreal and, in some cases, systemic antimicrobials. Systemic antimicrobials may be administered either intravenously or orally. In this article we review systemic antimicrobial options currently available for the treatment of types of endophthalmitis and the role of systemic antimicrobials (antibiotics and antifungals) in these treatments.

Review

While systemic antimicrobials are not universally utilized in the management of endophthalmitis, they may be helpful in some circumstances. The blood–retinal barrier affects the penetration of systemic medications into the posterior segment of the eye differently; for example, moxifloxacin and imipenem cross the blood–retinal barrier relatively easily while vancomycin and amikacin do not. However, inflammation, including endophthalmitis, may disrupt the blood–retinal barrier, enhancing the penetration of systemic agents into the eye.

Conclusion

Systemic antimicrobials may be particularly beneficial in patients with certain types of endophthalmitis; as such, they are standard treatment in the management of endogenous endophthalmitis (fungal and bacterial) and also widely used for prophylaxis and treatment of open-globe injuries. Although systemic antimicrobials are used in some patients with acute-onset postoperative endophthalmitis following cataract surgery, the literature generally does not support this practice. It is noted that there are currently no randomized clinical trials demonstrating a benefit of systemic antibiotics for any category of endophthalmitis.

Endophthalmitis in Advanced Microbial Keratitis: Risk Factors and Examination Findings

PURPOSE

To evaluate clinical and ultrasonographic findings associated with advanced microbial keratitis with concurrent endophthalmitis.

METHODS

We performed a retrospective analytical study of patients with severe microbial keratitis who underwent ocular ultrasonography for possible endophthalmitis at our institution over a 5-year period. Ocular and medical history, ocular examination findings, microbiology results, and ultrasonographic features were collected.

RESULTS

Of the 81 included eyes, 15 were diagnosed with endophthalmitis based on clinical findings and evidence of vitritis on ultrasound. Historical factors and physical examination findings more common in the endophthalmitis group than the keratitis-only group include presenting vision of light perception or no light perception (73.3% vs. 31.8%, P = 0.003), history of cataract surgery (80.0% vs. 45.5%, P = 0.02), and full thickness ulcer or perforation (33.3% vs. 9.1%, P = 0.03). Gram-positive organisms were more common in the endophthalmitis group (60.0% vs. 30.3%, P = 0.04). Ultrasound findings of choroidal thickening and retinal detachment were more common in the endophthalmitis group (26.7% vs. 3.4%, P = 0.01 and 13.3% vs. 8.4%, P = 0.04) in addition to the expected preponderance of membranous and dispersed vitreous opacities in that group. Final visual acuity was worse in the endophthalmitis group (2.3 vs. 3.5 LogMAR, P = 0.02).

CONCLUSIONS

Diagnosing endophthalmitis can be difficult in eyes with advanced microbial keratitis, and the visual outcomes are often extremely poor. Clinicians should have a particularly high index of suspicion in eyes presenting with light perception or no light perception vision, history of cataract extraction, full thickness ulcer or perforation, or choroidal thickening or retinal detachment on ultrasound.

The Spectrum of Microbial Keratitis: An Updated Review

Background:

In microbial keratitis, infection of the cornea can threaten vision through permanent corneal scarring and even perforation resulting in the loss of the eye. A literature review was conducted by Karsten, Watson and Foster (2012) to determine the spectrum of microbial keratitis. Since this publication, there have been over 2600 articles published investigating the causative pathogens of microbial keratitis.

Objective:

To determine the current spectrum of possible pathogens implicated in microbial keratitis relative to the 2012 study.

Methods:

An exhaustive literature review was conducted of all the peer-reviewed articles reporting on microbial pathogens implicated in keratitis. Databases including MEDLINE, EMBASE, Scopus and Web of Science were searched utilising their entire year limits (1950-2019).

Results:

Six-hundred and eighty-eight species representing 271 genera from 145 families were implicated in microbial keratitis. Fungal pathogens, though less frequent than bacteria, demonstrated the greatest diversity with 393 species from 169 genera that were found to cause microbial keratitis. There were 254 species of bacteria from 82 genera, 27 species of amoeba from 11 genera, and 14 species of virus from 9 genera, which were also identified as pathogens of microbial keratitis.

Conclusion:

The spectrum of pathogens implicated in microbial keratitis is extremely diverse. Bacteria were most commonly encountered and in comparison, to the review published in 2012, further 456 pathogens have been identified as causative pathogens of microbial keratitis. Therefore, the current review provides an important update on the potential spectrum of microbes, to assist clinicians in the diagnosis and treatment of microbial keratitis.

A Pyrrhic Victory: The PMN Response to Ocular Bacterial Infections

Some tissues of the eye are susceptible to damage due to their exposure to the outside environment and inability to regenerate. Immune privilege, although beneficial to the eye in terms of homeostasis and protection, can be harmful when breached or when an aberrant response occurs in the face of challenge. In this review, we highlight the role of the PMN (polymorphonuclear leukocyte) in different bacterial ocular infections that invade the immune privileged eye at the anterior and posterior segments: keratitis, conjunctivitis, uveitis, and endophthalmitis. Interestingly, the PMN response from the host seems to be necessary for pathogen clearance in ocular disease, but the inflammatory response can also be detrimental to vision retention. This “Pyrrhic Victory” scenario is explored in each type of ocular infection, with details on PMN recruitment and response at the site of ocular infection. In addition, we emphasize the differences in PMN responses between each ocular disease and its most common corresponding bacterial pathogen. The in vitro and animal models used to identify PMN responses, such as recruitment, phagocytosis, degranulation, and NETosis, are also outlined in each ocular infection. This detailed study of the ocular acute immune response to infection could provide novel therapeutic strategies for blinding diseases, provide more general information on ocular PMN responses, and reveal areas of bacterial ocular infection research that lack PMN response studies.

Trends in microbiological spectrum of endophthalmitis at a single tertiary care ophthalmic hospital in India: a review of 25 years

PURPOSE

To determine trends in the microbial spectrum of endophthalmitis over the past 25 years and to review its antibiotic susceptibility patterns over the last 10 years.

METHODS

Microbiology records of culture-positive endophthalmitis cases from 1991 to 2015 were reviewed. Additionally, data between 2005 and 2015 was also analyzed for trends in antibiotic susceptibility.

RESULTS

Of the total of 9278 patients, 3319 (35.7%) were culture positive and included bacteria (2840/3319, 85.56%), fungi (387/3319, 11.66%), and mixed cultures (92/3319, 2.7%). Gram-positive bacteria accounted for 67.68% (1922/2840) of the total bacteria seen, with the most prevalent pathogen being Streptococcus pneumoniae and Staphylococcus epidermidis. Among the gram-negative organisms Pseudomonas aeruginosa was the most prevalent while. Aspergillus flavus was the most common fungus isolated and Candida sp. accounted for 6.9% of the total fungi isolated. There was no significant change in the trends of bacteria isolated during the study period. Overall susceptibility patterns showed that gram-positive bacteria were most susceptible to vancomycin (96%) and fluoroquinolones (89%). The resistance to ceftazidime increased from 31% in 2005 to 62% in 2015 (P = 0.006) and amikacin decreased from 36% in 2005 to 33% in 2015 (P = 0.782). Although a significant trend (P < 0.001) toward increasing microbial resistance against cephalosporins and fluoroquinolones was observed, decreasing microbial resistance against glycopeptides and aminoglycosides was also detected.

CONCLUSION

The spectrum of pathogens causing endophthalmitis at our institute remained similar over the study period. These findings impact the empiric treatment and choice of antibiotics in patients with endophthalmitis.

Endoscopic vitrectomy in endophthalmitis: initial experience of 33 cases at a tertiary eye care center

Purpose

To report the presentation and management outcomes of endophthalmitis with endoscopic vitrectomy.

Methods

This is a retrospective interventional case series conducted at a tertiary eye care center in south India. Thirty three eyes of 33 patients were included. The medical records of the patients who underwent endoscopic vitrectomy for endophthalmitis from April 2014 to March 2018 were reviewed. Data with regard to age, gender, etiology of endophthalmitis, corneal and retinal examination, type of intervention, final anatomic and visual outcome, and the total follow-up were collected. The main outcome measures were the final visual acuity and evisceration rates.

Results

The mean age at presentation was 46.84±19.89 years, with a median age of 50 years. Based on etiology, 13 eyes (39.4%) were post-trauma endophthalmitis, eleven eyes (33.33%) were post-cataract surgery, three eyes (9.09%) were endogenous, three eyes (9.09%) were post-perforated corneal ulcer, two eyes (6.06%) were post-retinal surgery, and one eye (3.03%) was post-combined cataract and corneal surgery. Twenty-four eyes (72.72%) had a favorable anatomic outcome at the last visit, and five eyes (15.15%) had a favorable visual outcome. Of those with unfavorable visual outcome, ten eyes had further visual potential. Sixteen eyes (48.48%) showed a positive culture on microbiologic evaluation. The predominant organism isolated was Pseudomonas aeruginosa. Evisceration was required only in one eye (3.03%).

Conclusion

Endoscopic vitrectomy allows early management of endophthalmitis in spite of hazy media. This ensures a reasonable visual outcome, controls the infection, and reduces the incidence of evisceration in these eyes.

Clinical Analysis of 1593 Patients with Infectious Endophthalmitis: A 12-Year Study at a Tertiary Referral Center in Western China

Background:

Infectious endophthalmitis is a severe ocular inflammation which can cause devastating visual loss. The aim of the study was to identify the demographic and clinical features of infectious endophthalmitis in Western China for better prophylaxis and treatment of this disease.

Methods:

A retrospective, cross-sectional study was conducted based on the medical records of inpatients having infectious endophthalmitis in a tertiary referral center in Western China between 2005 and 2016.

Results:

The common cause of infectious endophthalmitis was trauma (82.6%), endogenous (7.8%), ophthalmic surgery (6.9%), and corneal ulcer with perforation (2.7%). These four etiological groups differed in age, gender, enucleation rate, visual outcome, etc. The number of cases in the first 6 years accounted for 38.7% of the total collection, which in the second 6 years accounted for 61.3%. The etiology patterns were different between these two periods. Altogether 51.3% of patients received pars plana vitrectomy, 13.9% of patients underwent evisceration, and the remaining 34.8% received other treatments. Of the 670 cases that had culture results, 266 (39.7%) were culture positive and 177 (66.5%) were Gram-positive organisms, 64 (24.1%) were Gram-negative organisms, 11 (4.1%) had fungal infection, and 14 (5.3%) were infected by multiple pathogens.

Conclusions:

There was an upward trend of the occurrence of infectious endophthalmitis in Western China for the past decade. The demographic and clinical characteristics of infectious endophthalmitis in Western China had its own characteristics and differed from those of developed countries. Here, open globe trauma was the most common cause of endophthalmitis, most traumatic endophthalmitis patients were male, and most of the injuries were work related, implicate that we should strengthen the education and application of ocular safety regulation specifically targeting the workplace.

Outcomes of combined keratoplasty and pars plana vitrectomy for endophthalmitis with compromised corneal clarity

IMPORTANCE

Studies evaluating combined penetrating keratoplasty and pars plana vitrectomy for infectious aetiologies are limited.

BACKGROUND

To evaluate the outcomes of combined penetrating keratoplasty and pars plana vitrectomy in patients with endophthalmitis and poor corneal clarity.

DESIGN

Retrospective interventional case series conducted at a tertiary care eye hospital in North India.

PARTICIPANTS

Review of records of 43 eyes of 43 patients. Mean age of patients was 53.39 ± 12.94 years (26 males). Patients with age > 14 years with minimum follow-up of 6 months were included.

METHODS

Combined penetrating keratoplasty and pars plana vitrectomy was performed in all eyes.

MAIN OUTCOME MEASURES

We analysed the preoperative, intraoperative and microbiological characteristics of patients undergoing combined surgeries. Anatomic and functional success and failure were pre-defined.

RESULTS

Aetiology for corneal opacification was corneal ulcer in 30(69.7%) eyes, corneal graft infection in eight(18.6%) eyes, bullous keratopathy in four (9.3%) eyes and corneal scar in one eye. Postoperative visual acuity improved in 20(46.5%) eyes, did not change in 14 (32.5%) eyes and deteriorated in nine eyes (20.9%). Anatomical failure (uncontrolled infection leading to phthisis bulbi or evisceration) was seen in 15 (34.8%) eyes. Microbiological analysis revealed bacterial growth in 26, fungal in 14 and no growth in three eyes. Fungal infection had a poorer outcome (P = 0.03). Six out of 11 monoocular patients regained ambulatory vision.

CONCLUSIONS AND RELEVANCE

Combined penetrating keratoplasty and pars plana vitrectomy is a complex but globe salvaging procedure for poor prognosis eyes which otherwise may need evisceration. Fungal infection carries a poorer prognosis.

Successful management of bee sting induced Aspergillus fumigatus endophthalmitis and scleritis

Ocular bee stings are known to cause corneal melts, corneal infiltrates, cataracts, and secondary glaucoma. Our patient presented with scleritis, corneal infiltrates, and endophthalmitis after a ocular bee sting. Topical treatment led to resolution of anterior segment inflammation, but the scleritis and vitreous inflammation worsened. Vitrectomy with intravitreal antibiotics was done and scrapings from the scleral abscess showed growth of Aspergillus fumigatus on culture. Repeat vitrectomy with silicone oil was needed for retinal detachment. Oral and intravitreal antifungals led to resolution of inflammation with attached retina. This is the first reported case of bee sting-induced fungal endophthalmitis with scleritis.

Microbial keratitis-induced endophthalmitis: incidence, symptoms, therapy, visual prognosis and outcomes

BACKGROUND

To evaluate symptoms, therapies and outcomes in rare microbial keratitis-induced endophthalmitis.

METHODS

Retrospective study with 11 patients treated between 2009 and 2014. Clinical findings, corneal diseases, history of steroids and trauma, use of contact lenses, number and type of surgical interventions, determination of causative organisms and visual acuity (VA) were evaluated.

RESULTS

The incidence of transformation from microbial keratitis to an endophthalmitis was 0.29% (n = 11/3773). In 90.9% (n = 10/11), there were pre-existent eyelid and corneal problems, in 45.5% (n = 5/11) rubeosis iridis with increased intraocular pressure and corneal decompensation, and in 18.2% (n = 2/11), ocular trauma. Specimens could be obtained in 10 of 11 samples: 33.3% of those 10 specimens were Gram-positive coagulase-negative Staphylococci (n = 3/10) or Gram-negative rods (n = 3/10) and 10.0% Staphylococcus aureus (n = 1/10). In 30% (n = 3/10), no pathogens were identifiable. 72.7% (n = 8/11) of all keratitis-induced endophthalmitis were treated with vitrectomy and 9.1% (n = 1/11) with amniotic-membrane transplantation. In 27.3% (n = 3/11) the infected eye had to be enucleated - 18.2% (n = 2/11) primarily, 9.1% (n = 1/11) secondarily. No patient suffered from sympathetic ophthalmia. The median initial VA was 2.1 logMAR (n = 11/11). At one month, median VA was 2.0 logMAR (n = 7/11), after three months 2.0 logMAR (n = 6/11), and after one year 2.05 logMAR (n = 6/11). The change in VA was not significant (p > 0.99). 36.4% (n = 4/11) of the cases resulted in blindness.

CONCLUSIONS

The overall outcome is poor. Enucleation should be weighed against the risk of local and systemic spread of the infection, prolonged rehabilitation and sympathetic ophthalmia.

Evaluation of the Effect of Topical Cyclosporine a with Impression Cytology in Dry Eye Patients

Purpose.

This study evaluated the efficacy of topical cyclosporine A 0.05% treatment with impression cytology in dry eye patients.

Methods.

Forty eyes of 40 patients with dry eye were included. Schirmer, tear break-up time, and Ocular Surface Disease Index (OSDI) scores and goblet cell densities were noted before and after 6 months of topical cyclosporine A treatment. Patients were graded clinically and biomicroscopically as follows: grade 1, 12 patients; grade 2, 18; and grade 3, 10 patients.

Results.

Mean age was 57.1±11.8 (23.0–80.0) years. A total of 36 (90%) of the patients were female and 4 (10%) were male. Mean Schirmer test value was 3.2±1.6 (0.0–8.0) mm in the beginning and was 8.4±4.3 (1.0–19.0) mm after 6 months of cyclosporine A topical treatment (p=0.00). At the first visit, mean tear break-up time was 4.4±1.8 (2.0–8.0) seconds. It increased to 11.8±4.8 (2.0–20.0) seconds at the end of the sixth month (p=0.00). Mean clinical grading was 1.9±0.8 (1.0–3.0) and this value regressed to 0.8±1.2 (0.0–3.0) after the treatment (p=0.00). Mean OSDI score was 30.0±11.7 (9.0–50.0) before the treatment and 21.3±11.0 (4.0–47.0) after the treatment (p=0.00). Mean goblet cell density of all cases was 12.3±8.7 before the treatment (2.0–28.0). It increased to 33.0±25.4 (6–70) after the treatment (p=0.04).

Conclusions.

Topical cyclosporine A treatment is effective in grade 1 and grade 2 dry eye patients but results are poor in grade 3 patients.

The Pathogenesis of Staphylococcus aureus Eye Infections

Staphylococcus aureus is a major pathogen of the eye able to infect the tear duct, eyelid, conjunctiva, cornea, anterior and posterior chambers, and the vitreous chamber. Of these infections, those involving the cornea (keratitis) or the inner chambers of the eye (endophthalmitis) are the most threatening because of their potential to cause a loss in visual acuity or even blindness. Each of these ocular sites is protected by the constitutive expression of a variety of antimicrobial factors and these defenses are augmented by a protective host response to the organism. Such infections often involve a predisposing factor that weakens the defenses, such as the use of contact lenses prior to the development of bacterial keratitis or, for endophthalmitis, the trauma caused by cataract surgery or intravitreal injection. The structural carbohydrates of the bacterial surface induce an inflammatory response able to reduce the bacterial load, but contribute to the tissue damage. A variety of bacterial secreted proteins including alpha-toxin, beta-toxin, gamma-toxin, Panton-Valentine leukocidin and other two-component leukocidins mediate tissue damage and contribute to the induction of the inflammatory response. Quantitative animal models of keratitis and endophthalmitis have provided insights into the S. aureus virulence and host factors active in limiting such infections.

Bacterial Contamination of Multi-dose Eye Drops at Ophthalmology Department, University of Gondar, Northwest Ethiopia

PURPOSE:

Ophthalmic solutions used for both diagnostic and therapeutic purposes were found to be contaminated with bacteria pathogens and caused serious ocular infections such as keratitis and endophthalmitis. The objective was to assess the magnitude and pattern of bacterial contamination of multi-dose ophthalmic medications and investigate the drug susceptibility pattern of the isolates in the Department of Ophthalmology at Gondar University Teaching Hospital.

METHODS:

A total of 100 ophthalmic medications in-use by patients and eye-care workers have been taken and cultured for potential bacterial contamination in the Microbiology Department after 1 week and >1 week of use. The dropper tip and the residual eye medications were examined for contamination. The contaminating bacteria were identified using a standard procedure and drug susceptibility testing to selected antimicrobial agents was done.

RESULTS:

Eleven ophthalmic medications were contaminated by different bacterial species with a prevalence of 11%. Multi-use and longer duration of use of eye medications were associated with higher rate of contamination. The contamination level ranges from 0% for antibiotics, 20% for local anesthetics, and 40% for povidone iodine. Among bacteria identified, Staphylococcus aureus and coagulase-negative Staphylococcus species were resistant to methicillin while others were sensitive to the antibiotics tested.

CONCLUSION:

The prevalence of contamination was low, but methicillin-resistant Staphylococcus was a potential risk. It is recommended that the Department of Ophthalmology should design set of rules about duration of use and safe handling of ophthalmic medications by the staff and patients.

Microbial characteristics of post-traumatic infective keratitis

PURPOSE

To determine the demographics, risk factors, clinical and microbiological characteristics, and treatment outcome of post-traumatic infective keratitis.

METHODS

Consecutive patients with post-traumatic infective keratitis presenting to the Ophthalmology Department of a tertiary referral hospital in Singapore between March 2012 and March 2016 were prospectively identified. A standardized data collection form was used to document patient demographics, microbiological diagnosis, antibiotic sensitivity, and pretreatment and posttreatment ocular characteristics. Any contact lens-induced keratitis was excluded from the study.

RESULTS

In total, 26 patients were included for analysis. The mean age was 40.0 years (SD ± 19.4) and 84.6% of the patients were male. The majority of the patients (69.2%, n = 18) had sustained work-related injury in their eyes. Gram-negative organisms were predominant isolates (75.0%, n = 12) in culture-positive corneal scrapings (n = 16). Pan-sensitive Pseudomonas aeruginosa was the commonest organism isolated among the culture-positive cases (56.2%, n = 9). Three patients (18.7%) had developed fungal keratitis and Acanthamoeba was isolated in 1 patient (6.2%) with polymicrobial keratitis. Infections resolved with medical treatment in 22 eyes (84.6%) and 4 eyes (15.3%) required therapeutic corneal transplantation.

CONCLUSIONS

A shift of practice in post-traumatic infective keratitis should be considered in tropical countries to include Gram-negative cover. Work safety practices with vigilance in initiating treatment and education by front-line physicians such as ophthalmology and general practitioners should be reinforced.

Risk factors for endophthalmitis requiring evisceration or enucleation

Endophthalmitis has devastating sequelae resulting in blindness and even loss of eyeball. Although the prognosis of endophthalmitis has much improved with the advances of antibiotics and vitreoretinal surgery, of the number of patients that required evisceration or enucleation is still significant. We retrospectively reviewed the charts of 210 eyes of 210 patients with endophthalmitis andcompared the group that required evisceration or enucleation with those that received salvaging therapies. Regression analysis was used to identify the risk factors for evisceration or enucleation. Thirty eyes (14.3%) underwent enucleation or evisceration. The group of eviscerated or enucleated eyes were older (58.7 vs. 42.2 years, p < 0.001), had more women (56.7% vs. 22.2%, p = 0.003), had poorer initial visual acuity (2.79 vs. 2.10 LogMAR, p < 0.001), and had longer duration before intervention (18.03 vs. 5.74 days, p = 0.031). The most common primary indications for endophthalmitis were infections from corneal ulcer (50.0% vs. 4.4%, p < 0.001) andfrom endogenous source (23.3% vs. 5.6%, p < 0.001). Less common indications were trauma (26.7% vs. 67.8%, p < 0.001) and postoperative (6.7% vs. 22.2%, p = 0.049) endophthalmitis. After adjusting for confounding factors, corneal ulcer-related endophthalmitis, endogenous endophthalmitis and initial visual acuity were the independent risk factors for evisceration or enucleation.

Current Perspectives of Prophylaxis and Management of Acute Infective Endophthalmitis

Endophthalmitis is an intraocular inflammatory condition which may or may not be caused by infective agents. Noninfectious (sterile) endophthalmitis may be attributable to various causes including postoperative retained soft lens matter or toxicity following introduction of other agents into the eye. Infectious endophthalmitis is further subdivided into endogenous and exogenous. In endogenous endophthalmitis there is hematogenous spread of organisms from a distant source of infection whereas in exogenous endophthalmitis direct microbial inoculation may occur usually following ocular surgery or penetrating eye injury with or without intraocular foreign bodies. Acute infective endophthalmitis is usually exogenous induced by inoculation of pathogens following ocular surgery, open-globe injury and intravitreal injections. More infrequently the infective source is internal and septicemia spreads to the eye resulting in endogenous endophthalmitis. Several risk factors have been implicated including immunosuppression, ocular surface abnormalities, poor surgical wound construction, complicated cataract surgery with vitreous loss and certain types of intraocular lens. Comprehensive guidelines and recommendations on prophylaxis and monitoring of surgical cases have been proposed to minimize the risk of acute endophthalmitis. Early diagnosis and prompt management of infective endophthalmitis employing appropriately selected intravitreal antibiotics are essential to optimize visual outcome.

Efficacy and Safety of Topical 0.05% Cyclosporine Eye Drops in the Treatment of Dry Eye Syndrome: A Systematic Review and Meta-analysis

A systematic review was performed to evaluate the safety and efficacy of topical 0.05% cyclosporine in treating patients with dry eye syndrome (DES). Twelve qualified randomized-controlled trials incorporating 1367 patients were analyzed. In comparison to controls, patients who were on topical 0.05% cyclosporine eye drops had lower Ocular Surface Disease Index scores (mean difference [MD]=4.10, 95% CI: 0.25-7.96, P=.04), longer tear film breakup time (MD=2.30 seconds, 95% CI: 0.75-3.86, P=.004), improved Schirmer I scores (MD=2.77 mm/5min, 95% CI: 1.63-3.91, P=.00001), reduced corneal fluorescein staining (standardized mean difference [SMD]=0.61, 95% CI: 0.07-1.15, P=.03), and higher goblet cell densities (SMD=1.68, 95% CI: 0.54-2.81, P=.004). However, there were more adverse effects in the cyclosporine patient group (odds ratio=1.64, 95% CI: 1.17-2.30, P=.004). Topical 0.05% cyclosporine eye drops twice daily significantly improved both the objective and subjective outcomes in DES patients. The study limitations in the clinical, methodological and statistical heterogeneities are discussed.

[Purulent corneal ulcers: clinical presentation, diagnosis, and conservative treatment]

This is a detailed review of purulent corneal ulcer signs and symptoms, problems in diagnosis, and conservative treatment options.

Aspergillus flavus endophthalmitis after penetrating keratoplasty combined with cataract phacoemulsification and IOL implantation

To report the clinical findings and management of a case of Aspergillus flavus endophthalmitis following penetrating keratoplasty (PKP) and combined cataract extraction. Clinical cornea appearance was evaluated by slit-lamp examination. Ocular ultrasonography was performed to evaluate the anterior chamber and vitreous cavity. The cornea was scraped. The corneal-scleral donor rim and media were cultured. The diagnosis of A. flavus infection was made. The patient received fortified antifungal drops (voriconazole 1 % solution) plus systemic voriconazole 400 mg/die. A second corneal transplant was performed, and the anterior chamber was cleaned and washed with a solution of voriconazole 1 %. At the end of follow-up, CDVA was 20/20 and slit-lamp examination showed a clear cornea graft. This case illustrates a severe A. flavus endophthalmitis after PKP and demonstrates the possibilities of visual function restoration. Furthermore, this case describes the different sources of fungal infection after PKP and the different clinical appearances.

Pharmacokinetics of intravenously administered tigecycline in eye compartments: an experimental study

PURPOSE

The purpose of this study was to evaluate the ocular distribution of intravenously administered tigecycline in a rabbit uveitis model.

METHODS

Tigecycline, which has a broad spectrum of activity against many gram-positive, gram-negative, and anaerobic organisms, was given intravenously to rabbits at 7 mg/kg of body weight starting 24 h after induction of uveitis by intravitreal endotoxin injection. Tigecycline concentrations were determined by high performance liquid chromatography-mass spectrometry (LC-MS/MS) assay in the aqueous humor, vitreous humor, and plasma 1, 3, 6, and 24 h after administration of a single dose.

RESULTS

The maximum concentrations were found within 1 h after the end of the intravenously given tigecycline, and were 1,308.60 ± 301.76 ng/mL in plasma, 181.40 ± 51.32 ng/mL in vitreous humor and 145.00 ± 55.29 ng/mL in aqueous humor of the inflamed eye. After 24 h, no drug was detectable in the aqueous and vitreous of the normal eyes, whereas small amounts of drug were detectable in inflamed eyes and in plasma.

CONCLUSIONS

Tigecycline did not reach therapeutically significant levels in the aqueous and the vitreous humor of rabbit eyes. The findings suggest a limited role for intravenously administered tigecycline in the treatment of bacterial endophthalmitis.

Aggressive Debridement Improves Outcome of Fungal Keratitis

PURPOSE

To study surgical debridement in the management of fungal keratitis in 44 patients.

DESIGN

A prospective randomized study.

METHODS

Patients with presumed fungal keratitis were randomized into 2 groups. The first group had diagnostic corneal scraping with a Kimura spatula while the second group underwent surgical debridement utilizing a motorized drill with attached diamond burr. Material obtained from both methods was plated on Sabaurauds medium, blood agar and stained for bacteria and fungi. Topical and systemic antifungal therapy was instituted, and patients were examined until resolution.

RESULTS

Pathogens were identified to a greater degree in the aggressive debridement group than in the Kimura spatula group. Patients who had aggressive debridement had a significant reduction in time to re-epithelialization and keratitis resolution (9.4 days) compared with the scraping group (17.1 days, P < 0.001). Mean uncorrected visual acuity (UCVA) in the surgical group was 1.02 logarithm of the minimal angle of resolution (logMAR) preoperatively and 0.43 logMAR postoperatively (P < 0.001). Mean UCVA in the Kimura spatula group was 1.20 logMAR before and 0.58 logMAR after scraping (P = 0.03). A single incidence of perforation occurred in the scraping group with the diagnosis of Fusarium made from the corneal button.

CONCLUSIONS

Aggressive debridement and debulking of fungal keratitis provides a faster clinical resolution with no reduction in visual potential. The acquisition of pathogens is more accurate with surgical debridement as compared with conventional scraping. Aggressive surgical debridement of keratitis not only aids in diagnosis but may also be therapeutic.

Infectious keratitis progressing to endophthalmitis: a 15-year study of microbiology, associated factors, and clinical outcomes

PURPOSE

To describe the incidence, microbiology, associated factors, and clinical outcomes of patients with infectious keratitis progressing to endophthalmitis.

DESIGN

Nonrandomized, retrospective, consecutive case series.

PARTICIPANTS

All patients treated for culture-proven keratitis and endophthalmitis between January 1, 1995 and December 31, 2009, at the Bascom Palmer Eye Institute.

METHODS

Ocular microbiology and medical records were reviewed on all patients with positive corneal and intraocular cultures over the period of the study. Univariate analysis was performed to obtain P values described in the study.

MAIN OUTCOME MEASURES

Microbial isolates, treatment strategies, and visual acuity (VA) outcomes.

RESULTS

A total of 9934 corneal cultures were performed for suspected infectious keratitis. Only 49 eyes (0.5%) progressed to culture-proven endophthalmitis. Fungi (n = 26) were the most common responsible organism followed by gram-positive bacteria (n = 13) and gram-negative bacteria (n = 10). Topical steroid use (37/49 [76%]) was the most common associated factor identified in the current study, followed by previous surgery (30/49 [61%]), corneal perforation (17/49 [35%]), dry eye (15/49 [31%]), relative immune compromise (10/49 [20%]), organic matter trauma (9/49 [18%]), and contact lens wear (3/49 [6%]). There were 27 patients in whom a primary infectious keratitis developed into endophthalmitis, and 22 patients in whom an infectious keratitis adjacent to a previous surgical wound progressed into endophthalmitis. Patients in the primary keratitis group were more likely to be male (22/27 [81%] vs 8/22 [36%]; P = 0.001), have history of organic matter trauma (8/27 [30%] vs 1/22 [5%]); P = 0.030), and have fungal etiology (21/27 [78%] vs 5/22 [23%]; P<0.001). Patients in the surgical wound-associated group were more likely to use topical steroids (20/22 [91%] vs 17/27 [63%]; P = 0.024). A VA of ≥ 20/50 was achieved in 7 of 49 patients (14%), but was <5/200 in 34 of 49 (69%) at last follow-up. Enucleation or evisceration was performed in 15 of 49 patients (31%).

CONCLUSIONS

Progression of infectious keratitis to endophthalmitis is relatively uncommon. The current study suggests that patients at higher risk for progression to endophthalmitis include patients using topical corticosteroids, patients with fungal keratitis, patients with corneal perforation, and patients with infectious keratitis developing adjacent to a previous surgical wound. Patients with sequential keratitis and endophthalmitis have generally poor visual outcomes.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Optimization and application of a reverse transcriptase polymerase chain reaction to determine the bacterial viability in infectious endophthalmitis

PURPOSE

To develop RNA based assay - reverse transcriptase polymerase chain reaction (RT-PCR) to detect viable bacteria in intraocular specimens obtained from patients with infectious endophthalmitis.

MATERIALS AND METHODS

Thirty-five intraocular specimens (19 vitreous fluid and 16 aqueous humor) collected from patients with typical infectious endophthalmitis were subjected to conventional and molecular microbiological investigations. Culture negative, eubacterial genome PCR positive intraocular specimens were subjected to denaturing high performance liquid chromatography (dHPLC) for separation of mixed genomes and subsequently identified by PCR based DNA sequencing. In parallel, RT-PCR was performed to detect the presence of viable bacteria in intraocular specimens.

RESULTS

Among 35 intraocular specimens, single bacterial genome was detected in 9 (25.7%) and two or more genomes in 26 (74.28%) intraocular specimens. Eubacterial genome was detected by RT-PCR in 29 (82.85%) specimens. PCR based dHPLC followed by PCR based DNA sequencing revealed the presence of 65 bacterial genomes in 35 intraocular specimens. Five novel genera namely Terrabacter species, Facklamia species, Xylella fastidiosa, Duganella species and Synechococcus species were detected.

CONCLUSION

RT-PCR serves as a rapid and reliable tool to detect viable bacteria causing endophthalmitis.

Endophthalmitis: A review of recent trends

Endophthalmitis is a feared complication of trauma, surgical procedures and septicemia. Although uncommon, its potential for significant visual loss is well recognized. Especially over the past decade, complicated surgeries and medical techniques have increased and seriously ill patients are being sustained in ever increasing numbers. New pathogens are being recognized and known ones reclassified thanks to advances in molecular analysis. Continuously evolving PCR methodologies also add a new dimension to the diagnosis of infectious endophthalmitis. As well, medical literature is now truly international, encompassing studies from around the world that expand our understanding of ocular infectious disease. This report reviews some of these changes as they relate to endophthalmitis and particularly to the spectrum of organisms involved.

[Therapeutic penetrating keratoplasty: indications and results in Tunisia]

PURPOSE

To report the experience of the Tunis Institute of Ophthalmology (Tunisia) in therapeutic penetrating keratoplasty.

METHODS

We retrospectively analyzed 35 patients after therapeutic penetrating keratoplasty over a period of 6 years (between September 2002 and September 2008).

RESULTS

The mean patient age was 49.3 years. Men outnumbered women by a ratio of 2.5 to 1. The mean follow-up was 13.5 months. Corneal diseases within a therapeutic penetrating keratoplasty were divided into infectious keratitis (21 eyes) and noninfectious diseases (14 eyes). Herpetic keratitis was the most common etiology (11 eyes). The anatomical success rate was 92.4%, with infection eradicated in 80% of cases. The graft clarity at the end of follow-up was 54.2%. Rejection was the leading cause of graft opacification (50%). Final visual acuity was better than 1/10 in 25.7% of patients. Recovery of useful vision was observed in 45.7% of patients.

CONCLUSION

Therapeutic penetrating keratoplasty is a surgical technique that has proved its effectiveness in maintaining the integrity of the eyeball. The prognosis for this intervention would probably be better if it could be postponed.