Risk factors, microbial profiles and prognosis of microbial keratitis-associated endophthalmitis in high-risk eyes

Ocular surface immune transcriptome and tear cytokines in corneal infection patients

Background

Microbial keratitis is one of the leading causes of blindness globally. An overactive immune response during an infection can exacerbate damage, causing corneal opacities and vision loss. This study aimed to identify the differentially expressed genes between corneal infection patients and healthy volunteers within the cornea and conjunctiva and elucidate the contributing pathways to these conditions' pathogenesis. Moreover, it compared the corneal and conjunctival transcriptomes in corneal-infected patients to cytokine levels in tears.

Methods

Corneal and conjunctival swabs were collected from seven corneal infection patients and three healthy controls under topical anesthesia. RNA from seven corneal infection patients and three healthy volunteers were analyzed by RNA sequencing (RNA-Seq). Tear proteins were extracted from Schirmer strips via acetone precipitation from 38 cases of corneal infection and 14 healthy controls. The cytokines and chemokines IL-1β, IL-6, CXCL8 (IL-8), CX3CL1, IL-10, IL-12 (p70), IL-17A, and IL-23 were measured using an antibody bead assay.

Results

A total of 512 genes were found to be differentially expressed in infected corneas compared to healthy corneas, with 508 being upregulated and four downregulated (fold-change (FC) <-2 or > 2 and adjusted p <0.01). For the conjunctiva, 477 were upregulated, and 3 were downregulated (FC <-3 or ≥ 3 and adjusted p <0.01). There was a significant overlap in cornea and conjunctiva gene expression in patients with corneal infections. The genes were predominantly associated with immune response, regulation of angiogenesis, and apoptotic signaling pathways. The most highly upregulated gene was CXCL8 (which codes for IL-8 protein). In patients with corneal infections, the concentration of IL-8 protein in tears was relatively higher in patients compared to healthy controls but did not show statistical significance.

Conclusions

During corneal infection, many genes were upregulated, with most of them being associated with immune response, regulation of angiogenesis, and apoptotic signaling. The findings may facilitate the development of treatments for corneal infections that can dampen specific aspects of the immune response to reduce scarring and preserve sight.

Infectious and Noninfectious Corneal Ulcers in Ocular Graft-Versus-Host Disease: Epidemiology, Clinical Characteristics, and Outcomes

PURPOSE

To evaluate the incidence, clinical characteristics, microbiological profile, and therapeutic outcomes of corneal ulcers in individuals with chronic ocular graft-vs-host disease (coGVHD).

DESIGN

Retrospective clinical cohort study.

METHODS

Review of individuals diagnosed with coGVHD following hematopoietic stem cell transplantation (HSCT) who were seen at the Bascom Palmer Eye Institute between May 2010 and November 2021. Baseline demographics, clinical characteristics, microbiological profile, risk factors for corneal ulceration, and treatment outcomes were collected. Etiology was deemed infectious in individuals with a positive culture or appropriate clinical scenario (presence of stromal infiltrate or hypopyon); otherwise, ulcers were presumed to be noninfectious. Treatment success was defined as reepithelialization with infiltrate resolution, and treatment failure as progression to corneal perforation or keratoplasty. Kaplan-Meier survival analysis estimated the incidence of ulceration. Cox regression analyses examined demographic and risk factors. Infectious and noninfectious ulcer groups were compared using 2-way independent t tests, 1-way analysis of variances, and χ2 tests, as appropriate.

RESULTS

173 individuals were included (53.7±14.4 years old; 59.0% male). Thirty-three individuals developed an ulcer 74.5±54.3 months after HSCT, with estimated 5- and 10-year incidences of 14% and 30%, respectively. Twenty-two (66.6%) ulcers were deemed infectious (15 microbiologically confirmed, 7 clinically) and 11 (33.3%) were deemed noninfectious. Risk factors for corneal ulceration included Black race (hazards ratio [HR] 2.89, 95% CI 1.30-6.42, P < .01), previous ocular surgery (HR 9.16, 95% CI 3.86-21.72, P < .01), eyelid margin abnormalities (HR 3.44, 95% CI 1.69-6.99, P < .01), and topical steroid use (HR 2.74, 95% CI 1.33-5.62, P < .01). Conversely, contact lens use reduced the risk of corneal ulceration (HR 0.29, 95% CI 0.13-0.66, P < .01). Infectious ulcers had a significantly higher frequency of treatment failure than noninfectious ulcers (57.1% vs 20.0%, P = .04).

CONCLUSION

Corneal ulceration is a potential complication of coGVHD, with several clinical features identified as risk factors. Infectious ulcers had worse outcomes than noninfectious ulcers.

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.

PM10 and Pseudomonas aeruginosa: effects on corneal epithelium

Purpose

In vivo data indicate that mouse corneas exposed to PM10 showed early perforation and thinning after infection with Pseudomonas aeruginosa. To understand the mechanisms underlying this finding, we tested the effects of PM10 and the mitochondria targeted anti-oxidant SKQ1 in immortalized human corneal epithelial cells (HCET) that were challenged with Pseudomonas aeruginosa strain 19660.

Methods

Mouse corneas were infected with strain 19660 after a 2 week whole-body exposure to PM10 or control air and assessed by clinical scores, slit lamp photography and western blot. HCET were exposed to 100μg/ml PM10 for 24h before challenge with strain 19660 (MOI 20). A subset of cells were pre-treated with 50nM SKQ1 for 1h before PM10 exposure. Phase contrast microscopy was used to study cell morphology, cell viability was measured by an MTT assay, and ROS by DCFH-DA. Levels of pro-inflammatory markers and anti-oxidant enzymes were evaluated by RT-PCR, western blot and ELISA. Reduced glutathione (GSH) and malondialdehyde (MDA) levels were evaluated by assay kits.

Results

In vivo, whole body exposure to PM10 vs. control air exposed mouse corneas showed early perforation and/or corneal thinning at 3 days post infection, accompanied by increased TNF-α and decreased SOD2 protein levels. In vitro, PM10 induced a dose dependent reduction in cell viability of HCET and significantly increased mRNA levels of pro-inflammatory molecules compared to control. Exposure to PM10 before bacterial challenge further amplified the reduction in cell viability and GSH levels. Furthermore, PM10 exposure also exacerbated the increase in MDA and ROS levels and phase contrast microscopy revealed more rounded cells after strain 19660 challenge. PM10 exposure also further increased the mRNA and protein levels of pro-inflammatory molecules, while anti-inflammatory IL-10 was decreased. SKQ1 reversed the rounded cell morphology observed by phase contrast microscopy, increased levels of MDA, ROS and pro-inflammatory molecules, and restored IL-10.

Conclusions

PM10 induces decreased cell viability, oxidative stress and inflammation in HCET and has an additive effect upon bacterial challenge. SKQ1 protects against oxidative stress and inflammation induced by PM10 after bacterial challenge by reversing these effects. The findings provide insight into mechanisms underlying early perforation and thinning observed in infected corneas of PM10 exposed mice.

Microbiological Characteristics and Risk Factors Involved in Progression from Fungal Keratitis with Hypopyon to Keratitis-Related Endophthalmitis

PURPOSE

To investigate the differences in microbiological characteristics, risk factors, drug resistance, and visual outcomes in three infections: fungal keratitis with hypopyon (FKH), keratitis-related fungal endophthalmitis (FKE), and fungal endophthalmitis without keratitis (FE).

METHODS

An analytical cross-sectional study.

RESULTS

In total, 14.57% of eyes with FKH progressed to endophthalmitis. Hypopyon, pre-existence of lens problems, topical steroid use and sever keratitis were significantly associated with the development of FKE. The risk factors of the FKH and FE group were mainly plant trauma and open globe trauma, respectively. Keratitis-related endophthalmitis (FKE) showed a significantly higher resistance than the other two groups. The FKH group had the best final visual acuity, while the FKE group had the worst.

CONCLUSION

Hypopyon height, pre-existing lens problems, topical steroid use and sever keratitis are risk factors for progression to endophthalmitis in eyes with fungal keratitis, and its progression is not affected by a single fungus. The antifungal drugs resistance in patients with endophthalmitis related to keratitis was significantly higher than that associated with other reasons. Timely diagnosis and risk factor assessment are essential for ensuring early treatment of FKE.

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.

Controlling the Evolution of Selective Vancomycin Resistance through Successful Ophthalmic Eye-Drop Preparation of Vancomycin-Loaded Nanoliposomes Using the Active-Loading Method

Vancomycin is the front-line defense and drug of choice for the most serious and life-threatening methicillin-resistant Staphylococcus aureus (MRSA) infections. However, poor vancomycin therapeutic practice limits its use, and there is a consequent rise of the threat of vancomycin resistance by complete loss of its antibacterial activity. Nanovesicles as a drug-delivery platform, with their featured capabilities of targeted delivery and cell penetration, are a promising strategy to resolve the shortcomings of vancomycin therapy. However, vancomycin's physicochemical properties challenge its effective loading. In this study, we used the ammonium sulfate gradient method to enhance vancomycin loading into liposomes. Depending on the pH difference between the extraliposomal vancomycin-Tris buffer solution (pH 9) and the intraliposomal ammonium sulfate solution (pH 5-6), vancomycin was actively and successfully loaded into liposomes (up to 65% entrapment efficiency), while the liposomal size was maintained at 155 nm. Vancomycin-loaded nanoliposomes effectively enhanced the bactericidal effect of vancomycin; the minimum inhibitory concentration (MIC) value for MRSA decreased 4.6-fold. Furthermore, they effectively inhibited and killed heteroresistant vancomycin-intermediate S.aureous (h-VISA) with an MIC of 0.338 μg mL^-1. Moreover, MRSA could not develop resistance against vancomycin that was loaded into and delivered by liposomes. Vancomycin-loaded nanoliposomes could be a feasible solution for enhancing vancomycin's therapeutic use and controlling the emerging vancomycin resistance.

Ocular streptococcal infections: A clinical and microbiological review

Streptococcus is a diverse bacterial genus that is part of the ocular surface microbiome implicated in conjunctivitis, keratitis, endophthalmitis, dacryocystitis, and orbital cellulitis which can lead to decreased visual acuity and require surgical intervention. The pathophysiology of S. pneumoniae is well established and the role of the polysaccharide capsule, pneumolysin, neuraminidases, and zinc metalloproteinases in ocular infections described. Additionally, key virulence factors of the viridans group streptococci such as cytolysins and proteases have been outlined, but there is a paucity of research on the remaining streptococcus species. These virulence factors tend to result in aggressive disease. Clinically, S. pneumoniae is implicated in 2.7-41.2% of bacterial conjunctivitis cases, more predominant in the pediatric population, and is implicated in 1.8-10.7% of bacterial keratitis isolates. Streptococcus bacteria are significantly implicated in acute postoperative, post-intravitreal, and bleb-associated endophthalmitis, responsible for 10.3-37.5, 29.4, and 57.1% of cases, respectively. Group A and B streptococcus endogenous endophthalmitis is rare, but has a very poor prognosis. Inappropriate prescription of antibiotics in cases of non-bacterial aetiology has contributed to increasing resistance, and a clinical index is needed to more accurately monitor this. Furthermore, there is an increasing need for prospective, surveillance studies of antimicrobial resistance in ocular pathogens, as well as point-of-care testing using molecular techniques.

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.

Endophthalmitis Caused by Pseudomonas aeruginosa: Clinical Characteristics, Outcomes, and Antibiotics Sensitivities

Purpose

The aim of this study is to report the clinical characteristics, visual outcomes, and antibiotic susceptibilities of patients with Pseudomonas aeruginosa endophthalmitis.

Methods

The medical records of patients with culture-proven Pseudomonas aeruginosa endophthalmitis treated from June 2013 to December 2019 were reviewed.

Results

This study included 36 eyes of 36 patients. The clinical settings included ocular trauma (15/36), corneal ulcer (9/36), postoperative endophthalmitis (5/36), endogenous (3/36), and unknown (4/36). Sixteen patients underwent evisceration, 13 patients underwent pars plana vitrectomy (PPV), 2 patients were treated with only intravitreal antibiotics, and 5 patients did not undergo surgery. Only one patient achieved a visual acuity of 20/400, and the others had all counting fingers or below. The cultured Pseudomonas aeruginosa was 100% sensitive to gentamicin, tobramycin, amikacin, ciprofloxacin, and levofloxacin and, approximately 95% sensitive to meropenem, imipenem, and aztreonam.

Conclusion

The visual outcomes of Pseudomonas aeruginosa endophthalmitis were very poor, and the evisceration rate remained high. Pseudomonas aeruginosa has good susceptibility to gentamicin, tobramycin, amikacin, ciprofloxacin, and levofloxacin.

Microorganisms and Antibiotic Resistance of Bacterial Keratitis at a Rural County Hospital in Seville

PURPOSE

To review the incidence, resistance patterns, and management of bacterial keratitis during the past 4 years.

METHODS

We retrospectively reviewed the clinical records of microbiological isolates from patients with a clinical diagnosis of bacterial keratitis.

RESULTS

A total of 159 patients were analyzed, and 102 microorganisms were isolated from 129 cultures. In these cultures, 23.7% of the microorganisms were gram positive, 60.8% were gram negative, and 15.5% were fungi. Pseudomonas aeruginosa was the most common bacteria (9.2%), followed by Serratia marcescens (4.4%) and Staphylococcus aureus (4%). Resistance to fluoroquinolones and aminoglycosides was found to be 23.1% and 53.1% in gram-positive and 2.8% and 13.9% in gram-negative bacteria, respectively. Resistance to ceftazidime against gram-negative bacteria was 13.9%. No resistance to vancomycin was observed.

CONCLUSIONS

A high resistance rate to aminoglycosides and fluoroquinolones was observed in gram-positive bacteria. We concluded that fluoroquinolones or aminoglycosides may not be suitable for initial monotherapy in patients with severe bacterial keratitis.

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.

Update on diagnosis and management of refractory corneal infections

Infectious keratitis is a medical emergency resulting in significant visual morbidity. Indiscriminate use of antimicrobials leading to the emergence of resistant or refractory microorganisms has further worsened the prognosis. Coexisting ocular surface diseases, delay in diagnosis due to inadequate microbiological sample, a slow-growing/virulent organism, or systemic immunosuppressive state all contribute to the refractory response of the ulcer. With improved understanding of these varied ocular and systemic factors contributing to the refractory nature of the microbes, role of biofilm formation and recent research on improving the bioavailability of drugs along with the development of alternative therapies have helped provide the required multidimensional approach to effectively diagnose and manage cases of refractory corneal ulcers and prevent corneal perforations or further dissemination of disease. In this review, we explore the current literature and future directions of the diagnosis and treatment of refractory keratitis.

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.

Condensins are essential for Pseudomonas aeruginosa corneal virulence through their control of lifestyle and virulence programs

Pseudomonas aeruginosa is a significant opportunistic pathogen responsible for numerous human infections. Its high pathogenicity resides in a diverse array of virulence factors and an ability to adapt to hostile environments. We report that these factors are tied to the activity of condensins, SMC and MksBEF, which primarily function in structural chromosome maintenance. This study revealed that both proteins are required for P. aeruginosa virulence during corneal infection. The reduction in virulence was traced to broad changes in gene expression. Transcriptional signatures of smc and mksB mutants were largely dissimilar and non-additive, with the double mutant displaying a distinct gene expression profile. Affected regulons included those responsible for lifestyle control, primary metabolism, surface adhesion and biofilm growth, iron and sulfur assimilation, and numerous virulence factors, including type 3 and type 6 secretion systems. The in vitro phenotypes of condensin mutants mirrored their transcriptional profiles and included impaired production and secretion of multiple virulence factors, growth deficiencies under nutrient limiting conditions, and altered c-di-GMP signaling. Notably, c-di-GMP mediated some but not all transcriptional responses of the mutants. Thus, condensins are integrated into the control of multiple genetic programs related to epigenetic and virulent behavior of P. aeruginosa.

Post penetrating keratoplasty infectious keratitis: Clinico-microbiological profile and predictors of outcome

PURPOSE

To study the clinico-microbiological profile, outcomes and prognostic factors of post penetrating keratoplasty (PKP) infectious keratitis.

METHODS

Retrospective review of medical records of 78 patients with post PKP infectious keratitis presenting between January 2014 and December 2018. Demographic, clinical and microbiological profile was documented and predictors of treatment and graft success were evaluated using univariate and subsequent multivariate logistic regression analysis.

RESULTS

Mean age of patients was 52.17 ± 15.51 years and mean infiltrate size was 19.39 ± 19.68 mm². Mean duration of presentation with infection post PKP was 11.66 ± 10.65 months. Culture positivity was seen in 64 eyes (82.05%). Bacterial growth was observed in 47 eyes (60.25%), fungal growth in 17 (21.79%) and no microbiological growth in 14 eyes (17.94%). At 3 months the visual acuity (VA) improved in 37 eyes (47.44%), did not change in 27 (34.62%) and deteriorated in 14 (17.95%). Graft failure was noted in 53 eyes (73.08%). Surgical intervention was needed in 47 (60.25%) eyes of which most common was therapeutic PKP in 32 eyes (41.02%). Treatment failure was noted with fungal infection (p = 0.05), poorer vision at presentation (p = 0.02), larger infiltrate area (p = 0.002) and graft infection developing before 1 year (p = 0.02). Graft failure was noted with associated endophthalmitis (p = 0.02), poorer VA at presentation (p = 0.01) and larger infiltrate area (p = 0.02).

CONCLUSION

Post PKP infectious keratitis is a sight threatening ocular condition. It is associated with high incidence of graft failure and frequently requires surgical intervention. Fungal etiology, larger infiltrate size, poorer vision at presentation and associated endophthalmitis carries a poorer prognosis.

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.

Endophthalmitis with opaque cornea managed with primary endoscopic vitrectomy and secondary keratoplasty: Presentations and outcomes

Purpose:

To describe the outcomes of endophthalmitis with opaque cornea managed with primary endoscopic vitrectomy and secondary keratoplasty.

Methods:

Retrospective consecutive interventional case series. All cases of endophthalmitis with opaque cornea which underwent endoscopic vitrectomy followed by secondary keratoplasty were analyzed. The study period was from Jan 2015 to March 2019. The outcome measures were resolution of infection, the magnitude of unnecessary keratoplasties avoided and corneal graft survival. The final anatomic and functional outcomes were reported and compared with relevant literature.

Results:

Seventy-eight eyes of 78 patients underwent endoscopic pars plana vitrectomy for endophthalmitis with the opaque cornea, of these 14 eyes of 14 patients were deemed eligible for further corneal intervention and were included in the study. The mean age at presentation was 42.27 ± 21.6 years (median 36 years). Etiology-wise, eight cases (57.14%) were post-trauma, three cases (21.42%) post-keratoplasty, two cases (14.28%) were endogenous, and one case (7.14%) following corneal dermoid excision and wound melt. Culture positivity was in 5/14 (35.71%). The mean interval between endoscopic vitrectomy and keratoplasty was 5.42 ± 2.69 months (median 3.5 months). The mean follow-up noted was 20.42 ± 11.45 months (median 17.5 months). The infection resolved in 100% of cases. Unnecessary keratoplasties were avoided in 64/78 (82%) cases due to the primary endoscopic intervention. The favorable anatomic outcome was seen in 11/14 (78.57%) of cases and favorable functional outcome in 8/14 (57.14%) cases.

Conclusion:

Endoscopic vitrectomy allows for early intervention in endophthalmitis with the opaque cornea. This facilitates early settlement of infection, globe preservation, greater graft survival, and lesser repeat posterior segment procedures.

Quantitative Ocular Ultrasound Findings in Microbial Keratitis-Associated Endophthalmitis

PURPOSE

To assess how ocular ultrasound findings correlate with clinical parameters of patients with infectious keratitis and concern for endophthalmitis and to evaluate the usefulness of ultrasound in managing these patients.

DESIGN

Retrospective study.

PARTICIPANTS

Seventy-three eyes of 73 patients with microbial keratitis who underwent ultrasound to evaluate for endophthalmitis were included.

METHODS

Ultrasound images were graded in a masked fashion independently by 2 retina specialists. The degree of vitreous opacities, defined as the largest area within the vitreous cavity occupied by opacities on any single image, were categorized as less than 10%, 10% to less than 50%, 50% to 90%, and more than 90%. The diagnosis of endophthalmitis was defined as severe intraocular inflammation that necessitated obtaining an intraocular culture sample and injection of intravitreal antimicrobials. The demographic and clinical characteristics of this patient cohort were compared.

MAIN OUTCOME MEASURES

Vitreous opacities measured quantitatively on ocular ultrasound.

RESULTS

The incidence of endophthalmitis in our patients with microbial keratitis who underwent ultrasound was 20.5%. Corneal and intraocular cultures showed positive results in 66.7% and 26.7% of endophthalmitis patients, respectively. A 4-fold increase in the likelihood of treatment for endophthalmitis was observed with increasing vitreous opacity severity (odds ratio, 3.97; confidence interval, 1.9-8.5; P < 0.0001). Endophthalmitis was associated with 50% or more vitreous opacities (P < 0.001), older age (P < 0.001), pseudophakia (P = 0.001), and hypopyon height (P < 0.001). Eye pain, eyelid edema, poor presenting visual acuity, larger corneal ulcer diameter, and causative organisms were not associated with endophthalmitis.

CONCLUSIONS

Patients with more severe vitreous opacities on ultrasound were more likely to be treated for endophthalmitis. Patients with microbial keratitis, who were older and pseudophakic, were prone to have more severe vitreous opacities.

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.

[Depth Effect of Cold Atmospheric Pressure Plasma in Keratitis Therapy: A Corneal Stroma Tissue Model]

The incidence of microbial keratitis has been increasing and is now 28 cases/100,000 inhabitants; this may be due to the more frequent use of contact lenses. Keratitis can lead to visual impairment and in severe cases with endophthalmitis to enucleation of the affected eye. As microorganisms are becoming more resistant to antibiotic therapy, there is a need for new therapeutic strategies. Cold atmospheric pressure plasma has already been successfully used to disinfect surfaces. This study investigates the efficacy of cold atmospheric pressure plasma against Escherichia coli in a depth-resolved corneal stroma tissue model.

Clinical Review of Microbial Corneal Ulcers Resulting in Enucleation and Evisceration in a Tertiary Eye Care Center in Hungary

Purpose

To analyse the clinical and microbiological characteristics and preexisting ophthalmic and systemic conditions of infectious keratitis resulting in enucleation/evisceration in a large tertiary referral center in a developed country (Hungary) over a period of 12 years. Patients and Methods. A retrospective review of enucleated/eviscerated eyes undergoing surgery between 2007 and 2018 at the Department of Ophthalmology of Semmelweis University, Budapest, Hungary, with infectious keratitis as the primary indication for enucleation or evisceration. For each subject, clinical history, B-scan ultrasound report, and microbiological analyses were reviewed.

Results

There were 48 enucleated/eviscerated eyes from 47 patients (29 females (61.7%), age at the time of surgery 66.4 ± 18.5 years). Indication for surgery was hopeless, unmanageable keratitis (62.5%), and keratitis with endophthalmitis (37.5%). The most common preexisting ophthalmic conditions were previous cataract surgery (60.4%), previous therapeutic penetrating keratoplasty (PKP) (56.3%), corneal perforation (52.1%), glaucoma (41.7%), and long-term topical steroid usage (31.3%). In order to treat keratitis, before enucleation or evisceration, 20 eyes (41.7%) underwent PKP, 12 eyes (25.0%) amniotic membrane transplantation, 8 eyes (16.7%) conjunctival autograft transplantation, 6 eyes (12.5%) tarsorrhaphy, and 4 eyes (8.3%) vitrectomy to salvage the eye prior to the final treatment of enucleation or evisceration. The most frequent preexisting systemic diseases were hypertension (62.5%), cardiac disease (20.8%), diabetes mellitus (20.8%), and rheumatoid arthritis (14.6%). Staphylococcus aureus (17.0%) and Propionibacterium acnes (12.8%) were the most commonly isolated gram-positive bacteria, and Pseudomonas aeruginosa was the most frequently isolated gram-negative pathogen bacterium (10.6%). Six globes (12.5%) had positive fungal cultures (1 case of Candida albicans, Candida parapsilosis, Trichosporon inkin, Acremonium sp., Fusarium sp., and Penicillium sp.).

Conclusions

Staphylococcus aureus, Propionibacterium acnes, and Pseudomonas aeruginosa keratitis with or without endophthalmitis represent the most common indication for ocular enucleation/evisceration in patients with microbial keratitis in a tertiary referral center in Hungary. The incidence of enucleation and evisceration related to mycotic keratitis does not seem to have increased within the last decade. Most frequent preexisting systemic diseases in cases of enucleation and evisceration are hypertension, cardiac disease, diabetes mellitus, and rheumatoid arthritis.

Gram-negative endophthalmitis: A prospective study examining the microbiology, clinical associations and visual outcomes following infection

IMPORTANCE

This is the largest Gram-negative endophthalmitis specific series and provides important evidence to guide management.

BACKGROUND

Endophthalmitis is a sight-threatening emergency. Gram-negative infections are associated with poorer visual outcomes; however, there is limited literature pertaining to this uncommon condition.

DESIGN

Prospective case series.

PARTICIPANTS

All patients presenting with endophthalmitis to a tertiary institution over a 20-year period.

METHODS

Data were collected prospectively and entered into a registry. Patients with microbiological evidence of Gram-negative infection were included in the analysis.

MAIN OUTCOMES MEASURES

Final visual acuity (VA), precipitating events, causative organisms, antibiotic sensitivity profiles and risk factors for poor visual outcomes were reported.

RESULTS

One hundred Gram-negative organisms were isolated in 97 eyes. Final VA was worse than 6/60 in 65 (67.0%) eyes at follow-up and 29 (29.9%) eyes were eviscerated or enucleated. Microbial keratitis (26.8%, n = 26) and Pseudomonas aeruginosa (34.0%, n = 34) were the most common precipitating event and causative organism, respectively. Eight (8.0%) isolates were third-generation cephalosporin resistant; of which, 7 (88.0%) were sensitive to ciprofloxacin. Preceding microbial keratitis (OR = 13.16, P = .015) or P. aeruginosa infections (OR = 3.40, P = .045) were strongly associated with poorer visual outcomes (worse than 6/60).

CONCLUSIONS AND RELEVANCE

Visual outcomes following Gram-negative endophthalmitis are extremely poor, with almost 30% of patients being eviscerated or enucleated. A majority of ceftazidime resistant organisms are sensitive to ciprofloxacin, providing evidence to support the empirical use of quinolones. Clinicians should be mindful that infections secondary to P. aeruginosa or microbial keratitis carry a particularly poor prognosis.

A SYBR Green based multiplex Real-Time PCR assay for rapid detection and differentiation of ocular bacterial pathogens

PURPOSE

Ocular bacterial pathogenesis is a serious sight threatening infection due to several bacterial species like Staphylococcus aureus, Streptococcus pneumoniae and Pseudomonas aeruginosa which are predominant. It is necessary to expedite diagnosis of pathogens for early treatment. Hence, a SYBR Green based multiplex Real-Time PCR assay coupled with melting curve analysis has been developed for rapid detection and differentiation of Staphylococcus aureus, Streptococcus pneumoniae and Pseudomonas aeruginosa in a single reaction.

METHODS

The assay was designed for simultaneous detection and differentiation of pathogens based on their distinct melting curve. The analytical specificity, sensitivity and reproducibility of the assay were examined using various reference strains. Clinical validation was carried out with 100 ocular samples collected from patients suffering from ocular infections.

RESULT

Each reaction tested for the targets individually generated three non overlapping melting curves with well alienated peaks corresponding to each gene. Among 100 ocular samples tested, 40 samples diagnosed with positive results in RT-PCR. Thus assay showed 100% specificity with high sensitivity and reproducibility.

CONCLUSION

The developed assay consistently established as a rapid and accurate diagnosis of ocular bacterial pathogens compared to the conventional laboratory techniques. Such precise method would aid greatly in clinical management of devastating ocular infections.

Nine-Year Analysis of Isolated Pathogens and Antibiotic Susceptibilities of Infectious Endophthalmitis from a Large Referral Eye Center in Southern China

Purpose

To analyze the pathogen spectrum of isolated pathogens and antibiotic susceptibility trends of infectious endophthalmitis over 9 years from a large referral eye center in southern China.

Methods

Data from all inpatients who were clinically diagnosed with infectious endophthalmitis and underwent microbiological evaluation at the Zhongshan Ophthalmic Center from January 2010 to December 2018 were collected retrospectively and analyzed according to different clinical etiologies.

Results

A total of 816 cases were collected in the study. Open-globe injuries had caused 473 (57.97%) cases, 70 (8.58%) cases presented endophthalmitis after infectious keratitis, 156 (19.12%) cases were postoperative, and endogenous causes accounted for 117 (14.34%) cases. Among the 309 culture-positive cases, the predominant pathogen for both postoperative and posttraumatic endophthalmitis was gram-positive cocci (59.52% and 49.72%, respectively). Regarding keratitis-related endophthalmitis, the main pathogens were filamentous fungi (57.58%) and gram-negative bacilli (30.30%). The pathogens of endogenous endophthalmitis were almost evenly distributed among gram-positive cocci, gram-negative bacilli, and fungi. Eighty-five (10.42%) cases underwent evisceration/enucleation, including 42 cases secondary to keratitis-related endophthalmitis. The incidence of evisceration/enucleation was much higher in keratitis-related endophthalmitis than the total endophthalmitis population (χ² =123.61, P<0.001). Overall bacteria showed high susceptibility to fluoroquinolones (75.36–100.00%). Gram-positive cocci showed much higher sensitivity to cephalosporins compared to gram-negative bacilli (85.11–92.59% vs 25.42–35.72%). For the five first-line antibiotics analyzed for time trend of susceptibility, four exhibited a significant decrease of susceptibility from 2010–2014 to 2015–2018.

Conclusion

Between 2010 and 2018, posttraumatic endophthalmitis was the most common form of the treated endophthalmitis in Zhongshan Ophthalmic Center. The causative pathogens varied according to different clinical settings. Even though the overall antibiotic susceptibilities were fairly high, we observed a substantial decrease of susceptibility for most first-line antibiotics.

Endophthalmitis in HIV Infection

Purpose: The role of HIV infection in exogenous and endogenous endophthalmitis has not been clarified. We aim to assess the potential role of HIV as a risk factor or a poor prognostic feature in this sight-threatening condition. Methods: Literature review. Review of evidence: Evidence for endophthalmitis in HIV patients is based on scarce retrospective case series and case reports. Infrequency of literature on this topic is owed to the diversity of the different types of endophthalmitis as well as the rarity of the coexistence of the two conditions. Conclusions: Endophthalmitis in HIV patients are a rare but potentially devastating condition. Many forms of endophthalmitis tend to occur in severely immunosuppressed HIV patients with low CD4 counts. Therefore, the early introduction of cART with full immune reconstitution is an essential part of the prevention of endophthalmitis in the HIV population.

Innovative Cold Atmospheric Plasma (iCAP) Decreases Mucopurulent Corneal Ulcer Formation and Edema and Reduces Bacterial Load in Pseudomonas Keratitis

Purpose

To evaluate the effect of application of 3% air in helium cold atmospheric plasma jet, using an inexpensive device termed iCAP, in corneal scratch wound closure in vitro and the treatment of Pseudomonas aeruginosa (P. aeruginosa) keratitis in vivo.

Methods

Thermal imaging to measure temperature of surfaces to which iCAP was applied and UV energy density delivered by iCAP were measured. Scratch wounds inflicted on in vitro cultures of a human corneal epithelial cell line were treated with iCAP and wound widths at various times post-application were measured. Rabbit eyes infected with P. aeruginosa were treated with iCAP and slit lamp biomicroscope examination conducted to determine corneal health outcomes 25h post infection. Corneal homogenates were plated on agar and viable bacterial colonies enumerated to determine the effect of iCAP on bacterial load in vivo in P. aeruginosa keratitis.

Results

iCAP was shown to operate in the non-thermal regime and also shown to deliver much lower UV energy density than that necessary to cause harmful effects on ocular tissue. iCAP treatment significantly improved the rate of scratch wound gap closure in vitro in a human corneal epithelial cell line compared to controls. In vivo, iCAP treatment of P. aeruginosa keratitis infection in the rabbit eyes (N = 20) significantly reduced the incidence of corneal ulcer (P = 0.003) and corneal edema (P = 0.011) and significantly improved total cornea health (P = 0.034) compared to untreated (N = 10). Finally, in vivo iCAP treatment of P. aeruginosa keratitis infection in the rabbit eyes (N = 19) significantly reduced bacterial loads (P = 0.012) compared to untreated (N = 9).

Conclusion

Our results strongly suggest that iCAP treatment was effective in improving corneal epithelial defect closure in vitro, reducing ulcer formation and decreasing inflammation in P. aeruginosa infected corneas in vivo and decreasing bacterial loads in P. aeruginosa infected corneas in vivo which led to improved overall cornea health outcomes in vivo. Further studies to investigate iCAP's safety and efficacy against other infectious microbes responsible for causing ulcerative keratitis, with and without co-treatment with antimicrobial therapies are warranted.

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.

Non-viral microbial keratitis in adults: clinical and laboratory aspects

This study compares patients with and without non-viral microbial keratitis in relation to sociodemographic variables, clinical aspects, and involved causative agent. Clinical aspects, etiology and therapeutic procedures were assessed in patients with and without keratitis that were diagnosed in an Eye Care Center in Campo Grande, MS, Brazil. Patients were divided into two groups: (a) cases: 64 patients with non-viral microbial keratitis diagnosed at biomicroscopy; and (b) controls: 47 patients with other eye disorders that were not keratitis. Labor activity related to agriculture, cattle raising, and contact lens use were all linked to keratitis occurrence (p < 0.005). In patients with keratitis, the most common symptoms were pain and photophobia, and the most frequently used medicines were fourth-generation fluoroquinolones (34.4%), amphotericin B (31.3%), and natamycin (28.1%). Microbial keratitis evolved to corneal perforation in 15.6% of cases; transplant was indicated in 10.9% of cases. Regarding the etiology of this condition, 23 (42.2%) keratitis cases were caused by bacteria (Pseudomonas aeruginosa, 12.5%), 17 (39.1%) by fungi (Fusarium spp., 14.1% and Aspergillus spp., 4.7%), and 4 (6.3%) by Acanthamoeba. Patients with keratitis present with a poorer prognosis. Rapid identification of the etiologic agent is indispensable and depends on appropriate ophthalmological collection and microbiological techniques.

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.

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.

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.

Glycyrrhizin Reduces HMGB1 and Bacterial Load in Pseudomonas aeruginosa Keratitis

Purpose

High mobility group box 1 (HMGB1) contributes to poor disease outcome in Pseudomonas aeruginosa keratitis. This study tests the prophylactic effect of treatment with HMGB1 inhibitors, glycyrrhizin (GLY) and its derivative, carbenoxolone (CBX), for Pseudomonas keratitis.

Methods

We treated C57BL/6 (B6) mice subconjunctivally with GLY or CBX, infected with a noncytotoxic clinical isolate (KEI 1025) or a cytotoxic strain (ATCC 19660) of P. aeruginosa, and injected intraperitoneally with either agent. Clinical score, photography with a slit lamp, real-time RT-PCR, ELISA, myeloperoxidase (MPO) assay, bacterial plate count, histopathology, and absorbance assays were used to assess treatment efficacy and bacteriostatic activity.

Results

After KEI 1025 infection, GLY treatment reduced HMGB1 (mRNA and protein levels) and improved disease outcome with significant reduction in mRNA levels of IL-1β, TLR4, CXCL2, and IL-12; protein expression (IL-1β, CXCL2); neutrophil infiltrate; and bacterial load. Treatment with GLY enhanced antimicrobial proteins, including CRAMP and mBD2, but not mBD3. Glycyrrhizin also reduced clinical scores and improved disease outcome in corneas infected with strain 19660. However, neither HMGB1 mRNA or protein levels were reduced, but rather, CXCL2 expression (mRNA and protein), neutrophil infiltrate, and bacterial load were reduced statistically. Treatment with GLY initiated 6 hours after infection reduced plate count; GLY also was bacteriostatic for KEI 1025 and ATCC 19660.

Conclusions

Glycyrrhizin reduces HMGB1 and is protective against P. aeruginosa-induced keratitis with a clinical isolate that is noncytotoxic. It was similar, but less effective when used after infection with a cytotoxic strain, which did not reduce HMGB1.

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.

Thrombomodulin Protects Against Bacterial Keratitis, Is Anti-Inflammatory, but Not Angiogenic

PURPOSE

Thrombomodulin (TM) is a multidomain, transmembrane protein with anti-inflammatory properties. Thrombomodulin domain (D) 1 is lectin-like, interacting with Lewis Y antigen on lipopolysaccharide, and with HMGB1, while TMD23 is associated with angiogenic and anti-inflammatory functions. Thus, we tested if TM is protective against Pseudomonas aeruginosa keratitis and whether it enhanced corneal vascularity.

METHODS

Eyes of C57BL/6 (B6) mice were injected with recombinant TM (rTM), rTMD1, or PBS subconjunctivally before and intraperitoneally after infection with P. aeruginosa. Clinical scores, photography with a slit lamp, RT-PCR, ELISA, myeloperoxidase (MPO) assay, viable bacterial plate counts, and India ink perfusion were used to assess the disease response and corneal vascularity (rTM only).

RESULTS

Recombinant TM versus PBS treatment reduced clinical scores and corneal opacity. Corneal mRNA levels for HMGB1 were unchanged, but proinflammatory molecules IL-1β, CXCL2, NF-κB, TLR4, and RAGE were decreased; anti-inflammatory molecules SIGIRR and ST2 were increased. ELISA confirmed the mRNA data for HMGB1, IL-1β, and CXCL2 proteins. Both neutrophil influx and viable bacterial plate counts also were decreased after rTM treatment. Protein levels for angiogenic molecules VEGF, VEGFR-1, and VEGFR-2 were measured at 5 days post infection and were not different or reduced significantly after rTM treatment. Further, perfusion with India ink revealed similar vessel ingrowth between the two groups. Similar studies were performed with rTMD1, but disease severity, mRNA, proteins, MPO, and plate counts were not changed from controls.

CONCLUSIONS

These data provide evidence that rTM treatment is protective against bacterial keratitis, does not reduce HMGB1, and is not angiogenic.

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.

ENDOPHTHALMITIS CAUSED BY PSEUDOMONAS AERUGINOSA: Clinical Features, Antibiotic Susceptibilities, and Treatment Outcomes

PURPOSE

To report the clinical features, antibiotic susceptibilities, and visual outcomes associated with endophthalmitis caused by Pseudomonas aeruginosa.

METHODS

A consecutive case series. Microbiology database records were retrospectively reviewed for all patients with endophthalmitis caused by P. aeruginosa from January 1, 2002, to December 31, 2012, at a large university referral center. The corresponding clinical records were then reviewed to evaluate the endophthalmitis clinical features and treatment outcomes.

RESULTS

In the 12 patients identified, clinical settings included postcataract surgery (n = 4), postpenetrating keratoplasty (n = 3), endogenous source (n = 2), post-pars plana vitrectomy (n = 1), trabeculectomy bleb-associated setting (n = 1), and glaucoma drainage implant-associated setting (n = 1). All patients presented with hypopyon. Presenting visual acuity was hand motions or worse in all cases. All isolates were susceptible to ceftazidime and levofloxacin. When comparing isolates in this study with isolates from a previous study (1987 to 2001), the minimal inhibitory concentration required to inhibit 90% of isolates (MIC 90, in micrograms per milliliter) remained the same for ceftazidime (8), ciprofloxacin (0.5), imipenem (4), tobramycin (0.5), and amikacin (4). Initial treatment strategies were vitreous tap and injection (n = 9) and pars plana vitrectomy with intravitreal antibiotics (n = 3). Final visual acuity was light perception or worse in 11 of the 12 patients (92%). Five patients underwent enucleation (42%).

CONCLUSION

All isolates were susceptible to ceftazidime and levofloxacin, and all MIC 90s for isolates in the current period compared with isolates from 1987 to 2001 remained identical. Despite early and appropriate treatment, outcomes were generally poor with a high rate of enucleation.

Presentation and Management Outcomes of Corneal and Scleral Perforations in Geriatric Nursing Home Residents

We compared the clinical presentation and treatment outcomes of corneal and scleral perforations in geriatric nursing home residents, geriatric community residents, and non-geriatric population. The medical records of patients who were treated for corneal and scleral perforations at the Prince of Wales Hospital, Hong Kong between January 1, 2004 and May 1, 2013, were reviewed retrospectively. Of 144 cases, 53 (37%) occurred in the geriatric population, of which 16 (11%) lived in nursing homes, and 37 (26%) were community residents. There were 91 (63%) patients in the non-geriatric group. The mean age of the patients in nursing home geriatric group was 86.5 years (87.5% females). The most common etiology of perforation was trauma. Rupture due to fall was more common in geriatric patients (P < 0.001) whereas laceration due to penetrating eye injury was more common in non-geriatric patients (P < 0.001). There were more cases of infection leading to spontaneous perforation in geriatric nursing home group compared to the other groups (P = 0.001). In the geriatric nursing home group, visual acuity at presentation (P < 0.001) and postoperative visual acuity (P = 0.012) was worse compared to the other groups. Our study showed that corneal and scleral perforations in the geriatric nursing home residents carry a poor visual prognosis. The causes and anatomical outcomes of such events in geriatric age group differ from those in the general population. In our study, geriatric patients residing in nursing homes had worse baseline as well as posttreatment visual acuity, compared to community residents.