Endophthalmitis: Pathogenesis, clinical presentation, management, and perspectives

Endophthalmitis in Eyes Treated with the Port Delivery System with Ranibizumab: Summary of Cases during Clinical Trial Development

PURPOSE

The Port Delivery System with ranibizumab (PDS) is approved in the United States for neovascular age-related macular degeneration. The United States Prescribing Information has a Boxed Warning for endophthalmitis and reports the incidence rate in patients developing endophthalmitis after receiving the PDS compared with monthly intravitreal ranibizumab. Endophthalmitis cases noted in the Boxed Warning, treatment outcomes, potential contributing factors, and potential mitigations are summarized.

DESIGN

Retrospective review of endophthalmitis cases in PDS-treated patients in the phase II Ladder (NCT02510794) and phase III Archway (NCT03677934) and Portal (NCT03683251) trials.

PARTICIPANTS

Endophthalmitis cases in the pooled all-PDS safety population (N = 555) including PDS patients in Ladder, Archway, or Portal.

METHODS

Ladder patients received PDS (10, 40, or 100 mg/ml) with pro re nata refill-exchanges. Archway patients received PDS 100 mg/ml with fixed refill-exchanges every 24 weeks (PDS Q24W). Portal patients received PDS Q24W from day 1.

MAIN OUTCOME MEASURES

Clinical features, management, and visual outcomes were summarized. Cases were summarized by date of PDS implant and/or refill, other prior invasive procedures/refills, and preceding/concurrent conjunctival complications.

RESULTS

Twelve endophthalmitis events were reported in 11 patients (11/555 [2.0%]) through March 12, 2021. All were cultured (3 were culture positive) and treated with intravitreal antibiotics. Two cases (2/555 [0.4%]) occurred in the immediate postoperative period (days 5 and 6). Nine cases occurred later (day range: 57-853), including 4 before the first refill-exchange (day range: 57-161). Five patients received between 1 and 11 refill-exchanges before the event (onset: 6-168 days after last refill-exchange). Seven cases (7/11 [63.6%]) had preceding/concurrent conjunctival complications. At last follow-up, 7 patients recovered vision to study baseline levels or ≥20/40; 4 patients experienced vision loss of ≥15 ETDRS letters.

CONCLUSIONS

Endophthalmitis is a serious complication that can endanger vision after any ocular procedure, including PDS implantation. Most, but not all, of this limited series of endophthalmitis cases were late onset, associated with conjunctival breach, and recovered vision with treatment. Meticulous attention to PDS surgical techniques with vigilant monitoring of conjunctiva during follow-up may minimize risk of endophthalmitis. Prompt treatment is critical for optimizing patient outcomes.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Bacterial pathogens and antimicrobial susceptibility in ocular infections: A study at Boru-Meda General Hospital, Dessie, Ethiopia

INTRODUCTION

The eye consists of both internal and external compartments. Several variables, including microbes, dust, and high temperatures can cause eye illnesses that can result in blindness. Bacterial eye infections continue to be a major cause of ocular morbidity and blindness, and their prevalence is periodically rising. The objective of the study was to detect bacterial pathogens and assess their susceptibility profiles to antibiotics in the ophthalmology unit of Boru-meda Hospital in Dessie, Ethiopia.

METHODS

A hospital-based cross-sectional study was conducted from February 1 to April 30, 2021, among 319 study participants with symptomatic ocular or peri-ocular infections who were enrolled using a consecutive sampling technique. After proper specimen collection, the specimen was immediately inoculated with chocolate, blood, and MacConkey agar. After pure colonies were obtained, they were identified using standard microbiological methods. The Kirby Bauer disk diffusion method was used to test antimicrobial susceptibility patterns, based on the guidelines of the Clinical and Laboratory Standards Institute.

RESULTS

The majority of participants developed conjunctivitis 126 (39.5%), followed by blepharitis 47 (14.73%), and dacryocystitis 45 (14.1%). Overall, 164 (51.4%) participants were culture positive, six (1.9%) participants had mixed bacterial isolates, giving a total of 170 bacterial isolates with an isolation rate of 53.3%. The predominant species was CoNS 47 (27.6%), followed by S. aureus 38 (22.4%) and Moraxella species 32 (18.8%). The overall Multi-Drug Resistance (MDR) rate was 62.9%, with 33 (44.6%) being gram-negative and 74 (77.1%) being gram-positive isolates.

CONCLUSION

Conjunctivitis was the dominant clinical case and CoNS, was the predominant isolate. A higher rate of MDR isolates, particularly gram-positive ones, was observed. Efficient peri-ocular or ocular bacterial infection surveillance, including microbiological laboratory data, is necessary for monitoring disease trends.

Endogenous bacterial endophthalmitis in an HIV patient with uncontrolled diabetes: A case of rare ocular complication

Endogenous bacterial endophthalmitis (EE) is an intraocular infection with a poor prognosis. Timely diagnosis and prompt treatment are crucial to prevent vision loss. In this communication, we describe a case of EE caused by Streptococcus pyogenes (Group A Streptococcus [GAS]) in an HIV-positive patient with poorly controlled type 2 diabetes mellitus (DM). A 60-year-old man with a history of HIV and poorly controlled type 2 diabetes, presented with progressive blurry vision, left eye pain, redness, and headache. EE was diagnosed based on the clinical presentation and gram stain analysis of blood culture. Treatment with vitreous tap, intravitreal, topical antibiotics, and systemic antibiotics significantly improved the patient's symptoms. The case highlights the rarity of GAS as a causative agent of EE, particularly in patients with risk factors such as HIV infection and DM.

A clinical metagenomic study of biopsies from Mexican endophthalmitis patients reveals the presence of complex bacterial communities and a diversity of resistance genes

Infectious endophthalmitis is a severe ophthalmic emergency. This infection can be caused by bacteria and fungi. For efficient treatment, the administration of antimicrobial drugs to which the microbes are susceptible is essential. The aim of this study was to identify micro-organisms in biopsies of Mexican endophthalmitis patients using metagenomic next-generation sequencing and determine which antibiotic resistance genes were present in the biopsy samples. In this prospective case study, 19 endophthalmitis patients were recruited. Samples of vitreous or aqueous humour were extracted for DNA extraction for metagenomic next-generation sequencing. Analysis of the sequencing results revealed the presence of a wide variety of bacteria in the biopsies. Resistome analysis showed that homologues of antibiotic resistance genes were present in several biopsy samples. Genes possibly conferring resistance to ceftazidime and vancomycin were detected in addition to various genes encoding efflux pumps. Our findings contrast with the widespread opinion that only one or a few bacterial strains are present in the infected tissues of endophthalmitis patients. These diverse communities might host many of the resistance genes that were detected, which can further complicate the infections.

Endogenous Fungal Endophthalmitis: A Single-Center Retrospective Study and Review of the Literature

PURPOSE

To evaluate factors that inform systemic antifungal choices in patients with endogenous fungal endophthalmitis (EFE).

DESIGN

Single-institution retrospective case series.

METHODS

Charts of EFE patients from 2010 to 2023 were reviewed. Patients treated systemically for EFE with a minimum of 14 days of follow-up were included. Outcome measures included time to improvement in vitritis or chorioretinitis, systemic therapy modification, and need for surgical intervention.

RESULTS

A total of 20 eyes of 16 patients were included. Candida species were most common (43.8%), followed by culture-negative EFE (37.5%) and Aspergillus species (18.8%). In all, 90% of eyes had vitritis and/or macula-involving chorioretinitis. The majority of Candida infections (60%) or culture-negative EFE (75%) were treated initially with oral antifungals. Patients with a history of immune compromise, positive fungal culture, or positive Fungitell assay were more likely to be treated with early intravenous (IV) antifungal therapy. Two patients required systemic antifungal therapy modification because of worsening chorioretinitis, in 1 case due to voriconazole-resistant Aspergillosis that demonstrated chorioretinal lesion growth despite intravitreal amphotericin B injections and systemic voriconazole, and in the second case due to worsening chorioretinitis from Candida dubliniensis infection that regressed upon switch from oral to IV fluconazole.

CONCLUSIONS

Initial systemic treatment decisions in patients with EFE were driven by systemic culture positivity, systemic symptoms, or comorbidities. Intravitreal antifungal therapy may be insufficient to arrest progression of chorioretinal lesions in some cases. Larger studies are needed to determine whether visible end-organ damage in the form of chorioretinitis may be useful for guiding systemic therapy changes.

Complement Cascade 8 - Alpha and Calpain-2 in Extracellular Vesicles of Human Vitreous as Biomarkers of Infectious Endophthalmitis

Purpose

Extracellular vesicles (EVs) are messenger pigeons of the cells that communicate about cellular microenvironment. In this study, we evaluated the expression of C8α and calpain-2 in EVs from vitreous of patients with bacterial endophthalmitis to assess its utility as a diagnostic marker.

Methods

EVs were isolated from vitreous of patients with bacterial endophthalmitis (culture positive and culture negative) and noninfectious control by exosome isolation reagent and characterized, and the levels of C8α and calpain-2 was assessed by enzyme-linked immunosorbent assay in isolated EVs and direct vitreous. The receiver operating characteristic curve was generated to assess the diagnostic performance.

Results

Scanning electron microscopy (SEM) and dynamic light scattering (DLS) confirmed the presence of EVs having a diameter (nm) of 275.2 ± 93, 92 ± 22, and 77.28 ± 12 in culture-positive (CP), culture-negative (CN), and control respectively. The expression level (ng/mL) of C8α in the EVs obtained from CP was 144 ± 22 and CN was 31.2 ± 9.8, which was significantly higher (P < 0.01) than control 3.7 ± 2.4. Interestingly, C8α is not expressed directly in the vitreous of CN and controls. Calpain-2 was significantly downregulated (P ≤ 0.0001) in CP (0.94 ± 0.16) and CN (0.70 ± 0.14) than control. The sensitivity and specificity of 1 for C8α and calpain-2 in the EVs implied that its diagnostic accuracy was significant.

Conclusions

This study showed that the EV proteins C8α and calpain-2 could be suitable diagnostic markers for endophthalmitis. However, the presence of C8α in the EVs of CN samples but not in direct vitreous promises EVs as the future of diagnostics.

Translational Relevance

Expression levels of EV-calpain-2 and EV-C8α could diagnose CN bacterial endophthalmitis.

The impact of antibiotic prophylaxis with intracameral cefuroxime on postoperative infectious endophthalmitis rates in a high-volume cataract surgery center

Our purpose was to compare postoperative infectious endophthalmitis rates before and after the introduction of antibiotic prophylaxis via intracameral with cefuroxime (ATB-P IC) in a high-volume cataract surgery service. Retrospective cohort study considering patients who underwent cataract surgery at Ophthal Hospital Especializado, São Paulo, Brazil, from January/2011 to December/2019. Patients operated from 2013 to 2019 comprised the ATB-P IC group while those operated from 2011 to 2013 formed the control group without the ATB-P IC protocol. A total of 23,184 cataract surgeries were included, with 6,207 in the Control Group and 16,977 in the ATB-P Group. A significantly higher rate of endophthalmitis was observed in the control group (0.0967%) when compared to the ATB-P group (0.0177%) (p = 0.014). Surgeries performed with ATB-P showed 80% less chance of reported endophthalmitis (OR = 0.20; 95% CI 0.05-0.72; p = 0.014) than those without ATB-P. Of the six cases confirmed by culture in the control group, all tested positive for Pseudomonas aeroginosa and the only case confirmed by culture in the ATB-P group was positive for Staphylococcus epidermidis. Our findings strongly support the use of intracameral antibiotic prophylaxis with cefuroxime to reduce postoperative infectious endophthalmitis rates, and we recommend its incorporation into cataract surgery protocols.

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.

A Novel and Low-cost Approach for Intravitreal Injection in an Experimental Model of Endophthalmitis

Purpose

Animal models are necessary in understanding the pathogenesis of endophthalmitis and are also necessary to assist the development of new therapeutics for this sight-threatening ocular inflammation. Hamilton syringes are usually preferred to inject pathogens when performing experiments on test subjects, however, this method has technical and financial disadvantages. In this study, we report the findings and assess the related benefits of applying a novel low-cost intravitreal injection technique to initiate endophthalmitis in a mouse model while using the Eppendorf tip and a 26G needle.

Methods

The 18-hr culture of clinical isolates of bacteria (Staphylococcus aureus and Pseudomonas aeruginosa) and fungus (Aspergillus flavus and Candida albicans) were resuspended to a final concentration of 10,000 colony forming units (CFU)/1 µL which were separately injected intravitreally into C57BL/6 mice (6-8 weeks) using a 0.1-2.5µL pipette attached to the modified Eppendorf tip with a 26G needle. The contralateral eye served as vehicle/uninjected control. Disease progression was determined by assessing the corneal haze, opacity, bacterial burden, and retinal histology of the eyes used in the model. Following euthanization, bacteria-infected mice were enucleated after 24 hr of the initial injection, and fungus-infected mice after 72 hr.

Results

Of the 50 mice injected, the modified technique was successful in 48 mice. Two mice were excluded due to cataract formed by accidental injury to the lens. The experimental endophthalmitis mice model successfully mimicked the natural clinical course. Clinical assessment and histopathology confirmed the influx of inflammatory cells into the posterior segment of the eye along with dissolution of retinal architecture.

Conclusion

Our novel method of injection using a modified Eppendorf tip and 26G needle yielded a cost-effective mouse model of clinical endophthalmitis, resulting in reproducible infection for understanding various aspects of its pathobiology.

Meibomian gland dysfunction and blepharitis: A common and still unsolved ophthalmic problem

Blepharitis and meibomian gland dysfunction (MGD) are very common, usually underdiagnosed and underappreciated diseases. More than 50% of patients seeking ophthalmologic consultations have symptoms and signs indicating one or both entities. We summarize the key points of diagnosis and management of both diseases, comparing the work of Dry Eye Workshop II (2017) with the dry eye blepharitis syndrome unification theory. The impact of MGD/blepharitis on ocular surgery also is described. Although MGD and blepharitis seem to be uncurable, most of the time they can be successfully controlled. Different management options are available, but the key to success remains simple-routine eyelid hygiene and moisturizing with the use of preservative-free lubricants.

Bilateral endogenous fungal endophthalmitis: A case report

RATIONALE

Endogenous fungal endophthalmitis is a challenging condition. There are no universally accepted diagnostic or management protocols. We share a case of endogenous fungal endophthalmitis who was successfully treated, focusing on the diagnostic and treatment procedures.

PATIENT CONCERNS

A 31-year-old female with a history of fungal vaginitis and tinea corporis presented with progressive visual decrease in both eyes after having an induced abortion. Her best corrected visual acuity at presentation was 20/1000 in her right eye and 20/250 in her left eye. Upon slit lamp examination, mild inflammatory reaction in the anterior chamber was found. Dilated fundus examination revealed a hazy view of the optic disc and posterior retina, and there was a whitish mass with "string and pearls" just in front of the macular region in each eye.

DIAGNOSES

Bilateral fungal endogenous endophthalmitis was diagnosed empirically, which was confirmed later by deoxyribonucleic acid sequencing and culture of intraocular fluid.

INTERVENTIONS

Oral itraconazole and intravitreal voriconazole were administered to the patient at first. The intraocular inflammation was partially responsive to the medication, yet the visual acuity persisted to deteriorate and the vitreous whitish masses became more prominent. Then vitrectomy procedures were carried out and oral itraconazle was switched to intravenous fluconazole. The antifungal treatment lasted for 8 weeks.

OUTCOMES

The intraocular inflammation alleviated and visual acuity improved after vitrectomy. At the 9-month follow-up visit, the patient's best corrected visual acuity was 20/40 in the right eye and 20/30 in the left eye. There was no intraocular inflammatary reaction, and retinal scar was noticed in each eye.

LESSON

Early and correct diagnosis, coupled with prompt and aggressive treatment, is crucial for cases of fungal endogenous endophthalmitis. Deoxyribonucleic acid sequencing techniques can contribute to early diagnosis, while vitrectomy may be necessary when antifungal medication is insufficient in controlling the condition.

Potential Strategies to Control the Risk of Antifungal Resistance in Humans: A Comprehensive Review

Fungal infections are becoming one of the main causes of morbidity and mortality in people with weakened immune systems. Mycoses are becoming more common, despite greater knowledge and better treatment methods, due to the regular emergence of resistance to the antifungal medications used in clinical settings. Antifungal therapy is the mainstay of patient management for acute and chronic mycoses. However, the limited availability of antifungal drug classes limits the range of available treatments. Additionally, several drawbacks to treating mycoses include unfavourable side effects, a limited activity spectrum, a paucity of targets, and fungal resistance, all of which continue to be significant issues in developing antifungal drugs. The emergence of antifungal drug resistance has eliminated accessible drug classes as treatment choices, which significantly compromises the clinical management of fungal illnesses. In some situations, the emergence of strains resistant to many antifungal medications is a major concern. Although new medications have been developed to address this issue, antifungal drug resistance has grown more pronounced, particularly in patients who need long-term care or are undergoing antifungal prophylaxis. Moreover, the mechanisms that cause resistance must be well understood, including modifications in drug target affinities and abundances, along with biofilms and efflux pumps that diminish intracellular drug levels, to find novel antifungal drugs and drug targets. In this review, different classes of antifungal agents, and their resistance mechanisms, have been discussed. The latter part of the review focuses on the strategies by which we can overcome this serious issue of antifungal resistance in humans.

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.

Endogenous endophthalmitis due to Serratia marcescens secondary to late-onset empyema Post-Cardiac surgery in an End-Stage renal disease patient on peritoneal dialysis

Endogenous bacterial endophthalmitis results from bacterial seeding of the eye during bacteremia. A diagnosis of endogenous bacterial endophthalmitis requires clinical findings such as vitritis or hypopyon along with positive blood cultures. Serratia marcescens is the second most common pathogen causing hospital-acquired ocular infections. This report describes a case of endogenous bacterial endophthalmitis caused by S. marcescens in an older adult with end-stage renal disease (ESRD) on peritoneal dialysis, who had late-onset pleural empyema secondary to coronary artery bypass grafting (CABG). A 61-year-old gentleman presented with a two-day history of cloudy vision, black floaters, pain, swelling, and gradual vision loss in his right eye. There was no history of trauma, ocular surgeries, or previous similar episodes. He had myocardial infarction treated with CABG 3 months back. Examination showed a 3 mm hypopyon in the anterior chamber. He had classic signs of endophthalmitis with positive blood cultures for S. marcescens. He was treated with high-dose intravenous meropenem and intravitreal ceftazidime without vitrectomy. Endophthalmitis progressed to complete vision loss in his right eye, requiring evisceration. Endophthalmitis caused by S. marcescens is rare, but long-term outcomes can be severe, causing complete vision loss in about 60% of the patients. It is usually hospital-acquired, and the source can be late-onset empyema several months after cardiac surgery, in an immunocompromised patient. Systemic antibiotics should be supplemented with intravitreal agents with or without pars plana vitrectomy.

Endogenous Endopthalmitis in Disseminated Methicillin-Sensitive Staphylococcus aureus (MSSA) Bacteremia

Endogenous endophthalmitis (EE) is an ocular infection resulting from hematogenous spread from the remote primary source. Risk factors include endocarditis, bacteria meningitis, immunosuppressive state, and invasive procedures in patients with sepsis. We present a case of a 43-year-old gentleman with poorly controlled diabetes mellitus who was admitted for bilateral nasoseptal cellulitis with a right nasal wall abscess and right vocal cord palsy. At presentation, he just had preseptal cellulitis without any posterior segment involvement. He underwent incision and drainage under the Otorhinolaryngology team. Unfortunately, postoperatively he developed sepsis with a hematogenous spread of infection systemically involving his right eye (endophthalmitis) and his heart valve (infective endocarditis). Blood culture revealed Methicillin Sensitive Staphylococcus Aureus (MSSA) infection. He had six weeks of intravenous cloxacillin and three times intravitreal injections of vancomycin and ceftazidime with complete resolution of signs and symptoms. In the case of a poorly controlled diabetic patient with an extensive regional infection, the presence of ocular symptoms and signs that are suggestive of EE must be taken seriously and warrant a complete eye examination as early detection and treatment of EE is crucial for better prognosis.

Visual Outcomes and Prognostic Factors of Traumatic Endophthalmitis Treated by Pars Plana Vitrectomy: 11 Years Retrospective Analysis

Aim: To evaluate the visual outcome of traumatic endophthalmitis and describe the risk factors associated with poor visual acuity and retinal detachment (RD) development over an 11-year period. Methods: Medical records of 34 patients with traumatic endophthalmitis who underwent PPV over a period of 11 years (1 January 2010−31 December 2020) were reviewed. We extracted details regarding demographic data, initial and final best corrected visual acuity (BCVA) using a standard Snellen chart, wound and IOFB characteristics, ocular associated lesions, and treatment. The outcome was evaluated according to the final BCVA which was defined as poor < 0.1 or good ≥ 0.1 Results: Endophthalmitis rate was 29.8% in open globe injuries. The mean age was 43.6 ± 16.5 years and the majority of patients were males (32 out of 34, 94.1%). All patients received systemic (moxifloxacin) and intravitreal antibiotherapy. We performed pars plana vitrectomy (PPV) in all cases. Poor visual outcome was associated with wound size ≥ 3 mm (p = 0.02), the association of IOFB (p = 0.016), and the development of RD (p = 0.00). The presence of IOFB (p = 0.01) and wound size ≥ 3 mm (p = 0.01) were statistically associated with RD development. After treatment, 47.05% of patients achieved final BCVA ≥ 0.1. Conclusion: Wound size ≥ 3 mm, IOFB and RD were risk factors for poor visual outcomes in traumatic endophthalmitis.

Recent Advances and Ongoing Challenges in the Diagnosis of Culture Negative Endophthalmitis

BACKGROUND

Culture negative (CN) but presumed infectious endophthalmitis poses a huge diagnostic challenge in terms of clinical management. This article outlines the current state of knowledge of infectious endophthalmitis with negative cultures and summarizes the recommendations for the work up of this condition along with providing a simple algorithm, by putting into context the recent concerns about over-diagnosing endophthalmitis.

METHODS

We searched the PubMed and Scopus databases for large hospital based studies on diagnosis of endophthalmitis, with emphasis on culture-negative infections in October 2021. Only clinical studies written in English were included. Basic science studies, letters to the editor and case reports on endophthalmitis were excluded.

RESULTS

Twenty studies were included in this study. The prevalence of CN endophthalmitis ranged from 40% to 70%. Recent advances in PCR along with high throughput sequencing have helped identify the etiological agent in most cases but these technologies are not easily available, requires advanced bioinformatic analysis and are not cost effective. Role of other inflammatory and relatively low-cost biomarkers in diagnosing a presumed infection is yet to be validated clinically but hold promise in helping ophthalmologists identify the causative agent.

CONCLUSIONS

CN endophthalmitis is a relatively frequent finding and should not be labelled as sterile endophthalmitis. Recent advances provide a new perspective for ophthalmologist in diagnosis of presumed infectious endophthalmitis and further studies are needed to confirm their utility in clinical settings.

Age-related macular degeneration: A disease of extracellular complement amplification

Age-related macular degeneration (AMD) is a major cause of vision impairment in the Western World, and with the aging world population, its incidence is increasing. As of today, for the majority of patients, no treatment exists. Multiple genetic and biochemical studies have shown a strong association with components in the complement system and AMD, and evidence suggests a major role of remodeling of the extracellular matrix underlying the outer blood/retinal barrier. As part of the innate immune system, the complement cascade acts as a first-line defense against pathogens, and upon activation, its amplification loop ensures a strong, rapid, and sustained response. Excessive activation, however, can lead to host tissue damage and cause complement-associated diseases like AMD. AMD patients present with aberrant activation of the alternative pathway, especially in ocular tissues but also on a systemic level. Here, we review the latest findings of complement activation in AMD, and we will discuss in vivo observations made in human tissue, cellular models, the potential synergy of different AMD-associated pathways, and conclude on current clinical trials and the future outlook.

Early Vitrectomy: An Effective Treatment for Acute Postcataract Surgery Endophthalmitis

Background

Endophthalmitis is a rare but a high morbid complication after cataract surgery, and a gold standard treatment is not recommended yet. In this study, we aim to evaluate the effect of early vitrectomy on the visual acuity of patients with postcataract endophthalmitis.

Materials and Methods

This study was a single-arm clinical trial on 27 patients with postcataract surgery endophthalmitis. Early vitrectomy was the intervention. Visual acuity as the primary outcome was evaluated and compared at baseline, at discharge, and 1 and 3 months after the intervention.

Results

From 27 patients who included in our study, six patients gain favorable visual acuity of 5/10 and above (success rate = 22%), and four of them have no improvement in their visual acuity. Retinal detachment was reported as a complication in just one case. Negative culture was a predictor for success in terms of visual acuity after the surgery. All patients who gain favorable results, presented in the first 15 days after the cataract surgery.

Conclusion

The result of our study showed that, considering complete, early vitrectomy for the treatment of postcataract surgery endophthalmitis, especially for those who presented in the first 15 days of cataract surgery and for those who have negative culture is promising.

Temporal Transcriptome Analysis Suggests Modulation of Key Pathways and Hub Genes in a Mice Model of Multi-Drug Resistant (MDR) Pseudomonas aeruginosa Endophthalmitis

PURPOSE

Increasing incidence of multidrug-resistant Pseudomonas aeruginosa (MDR-PA) causing endophthalmitis challenges our ability to manage this vision-threatening condition. In this study, temporal dynamics of immune response in a mouse model of MDR-PA endophthalmitis was investigated by whole transcriptome analysis.

METHODS

C57BL/6 mice were infected with MDR-PA and antibiotic susceptible (S-PA) clinical strains and disease severity were monitored at 6 and 24-h postinfection (p.i), following which eyeballs were enucleated. Microarray analysis was performed using SuperPrint G3 Mouse Gene Expression v2 chip and the differential gene expression analysis was performed with limma package in R (v4.0.0.)/Bioconductor (v3.11).

RESULTS

Histopathological analysis revealed a significant difference in retinal architecture and vitreous infiltrates at 6 and 24 h. In comparison to S-PA, MDR-PA revealed altered expression of 923 genes at 6 h and 2220 genes at 24 h. Further, 23 and 76% of these altered genes and its downstream interacting proteins showed time-specific expression (6 and 24 h respectively), indicating their association with disease progression. At 24 hours, MDR-PA induced endophthalmitis showed aberrant immune response with the enrichment inflammasome signalling, dysregulated ubiquitination, complement cascade, MMPs NF-κβ and IL-1 signalling.

CONCLUSION

The rapid development of transcriptional differences between the two-time points reveals that distinct genes contribute to disease severity. The results from this study highlighted a link between innate and adaptive immune responses and provided novel insights in the pathogenesis of MDR-PA endophthalmitis by extending the number of molecular determinants and functional pathways that underpin host-associated damage.

Proteome profiling of Extracellular Vesicles in Pseudomonas aeruginosa endophthalmitis: Prognostic and therapeutic significance in a mouse model

Endophthalmitis is a sight-threatening infection and a serious consequence of complications during intraocular surgery or penetrating injury of which Pseudomonas aeruginosa is an important etiology. Extracellular vesicles (EVs) have evolved as a promising entity for developing diagnostic and therapeutic biomarkers due to their involvement in intracellular communication and pathogenesis of diseases. We aimed to characterise the protein cargo of extracellular vesicles, isolated from a murine (C57BL/6) model of P. aeruginosa endophthalmitis by LC-MS/MS at 24 h post infection (p.i). EVs were extracted by ultracentrifugation, characterized by Dynamic Light Scattering (DLS) and western blotting with tetraspannin markers, CD9 and CD81 and quantified by the ExoCet quantification kit. Multiplex ELISA was performed to estimate the levels of TNF-α, IL-6, IFN-γ and IL-1β. Proteomic analysis identified 2010 proteins (FDR ≤0.01) in EVs from infected mice eyes, of which 137 were differentially expressed (P-value ≤ 0.05). A total of 101 proteins were upregulated and 36 were downregulated. Additionally, 43 proteins were exclusive to infection set. KEGG and Gene Ontology revealed, Focal adhesion, Phagosome pathway, Complement cascade and IL-17 signalling pathway are crucial upregulated pathways involving proteins such as Tenascin, caveolin 1, caveolin 2, glutamine synthetase, microtubule-associated protein, C1, C8 and IL-17. Tenascin and caveolins are known to suppress anti-inflammatory cytokines further exacerbating the disease. The result of this study provides insight into the global extracellular vesicle proteome of P. aeruginosa endophthalmitis with their functional correlation and distinctive pattern of expression and tenascin, caveolin 1 and caveolin 2 are attractive biomarkers for P. aeruginosa endophthalmitis.

Endophthalmitis: Ursachen, Erreger, Therapie und Visusverlauf mit Fokus auf Glaukompatienten

Hintergrund Endophthalmitiden stellen einen der schwerwiegendsten Notfälle in der Ophthalmologie dar. Um deren Prävalenz zu minimieren, ist eine möglichst genaue Kenntnis auslösender Faktoren von Bedeutung. Eine chirurgische Therapie mit gezielter, Erreger-spezifischer Medikation und ein intaktes Immunsystem sind die Basis für den Visuserhalt. Ferner stellt sich die Frage, ob anhand zugrundeliegender Erkrankungen am Auge ein ungünstiger Verlauf prognostiziert werden kann, sodass ein Vergleich zwischen Glaukom- (G) und Nicht-Glaukompatienten (NG) im Hinblick auf ursächliche Faktoren, Erreger, Therapie und Visusverlauf gezogen wurde. Da bei Glaukompatienten eine potentielle Alteration des lokalen Immunsystems diskutiert wird, ist von Interesse, ob sich die klinischen Verläufe einer Endophthalmitis von Nicht-Glaukompatienten unterscheiden. Patienten und Methoden Es handelt sich um eine retrospektive Analyse von 75 Augen (13 G, 62 NG), die in einem 5-Jahres-Zeitraum aufgrund einer Endophthalmitis an der Augenklinik des Universitätsklinikums Erlangen-Nürnberg behandelt wurden. Auszuwertende Parameter waren u.a. das klinische Bild, operative und medikamentöse Behandlungen, das mikrobielle Spektrum und der Visusverlauf bei Glaukom- sowie Nicht-Glaukompatienten. Ergebnisse Bei Erstvorstellung dominierte bei allen Patienten eine akute Visusverschlechterung (44%) mit Vorderkammerreiz (62,7%), Hypopyon (52%) und reduziertem (40%) oder fehlendem (26,7%) Funduseinblick. Vorangehende intraokulär-chirurgische Eingriffe wurden bei insgesamt 53,3% beobachtet, insbesondere Kataraktoperationen. In beiden Gruppen konnten gram-positive Kokken als häufigster Erreger identifiziert werden (G: 23,1%; NG: 38,7%), wohingegen seltene Keime nur bei Glaukompatienten vorkamen. Bei 76% aller Patienten wurde eine pars-plana-Vitrektomie durchgeführt, eine Enukleation bei 20%, letzteres signifikant häufiger bei Glaukompatienten (p=0,01). Postoperativ konnte eine signifikante Visusverbesserung bei Nicht-Glaukompatienten erzielt werden (p<0,001); im Direktvergleich stellte sich ein schlechteres visuelles Outcome bei glaukomatös vorerkrankten Augen dar. Schlussfolgerung Stellt die Endophthalmitis eine sehr seltene Erkrankung dar, ist eine frühzeitige Diagnosestellung und Behandlung dennoch für die Prognose entscheidend. In der vorliegenden Kohorte zeigt sich ein schlechterer Endvisus bei Glaukompatienten als bei Nicht-Glaukompatienten. Background Endophthalmitis is one of the most serious emergencies in ophthalmology. In order to lower their prevalence, the most accurate knowledge of potential risk factors is important. Surgical therapy with targeted, pathogen-specific medication and an intact immune system are fundamental to preserve visual acuity. Furthermore, the question arises whether an unfavorable course can be predicted on the basis of underlying diseases of the eye, therefore a comparison between glaucoma patients (G) and non-glaucoma patients (NG) with regard to causative factors, pathogens, therapy and visual acuity course was drawn. Since a potential alteration of the local immune system in glaucoma disease has been described, it is of interest whether the clinical courses of endophthalmitis differ from non-glaucoma patients. Patients and methods A retrospective analysis of 75 eyes (13 G, 62 NG) who underwent treatment and surgery due to the diagnosis of endophthalmitis in the Department of Ophthalmology, University of Erlangen-Nuremberg has been evaluated over a period of 5 years. Clinical characteristics, surgical treatment, microbial spectrum and visual acuity in glaucoma and non-glaucoma eyes were investigated. Results A drastic vision impairment (44%) with inflammation of the anterior chamber (62.7%), hypopyon (52%) and reduced (40%) or complete missing sight (26.7%) of the fundus were predominantly present at first diagnosis in all patients. A previous eye surgery was observed in a total of 53%, especially cataract surgery. Gram-positive cocci were seen as the most common causing agent in both groups, (G: 23.1%; NG: 38.7%), whereas other rare pathogens were present only in glaucoma eyes. Pars-plana-vitrectomy was performed in 76% and enucleations in 20% of all patients, the latter significantly increased in glaucomateous eyes (p=0.01). A significant postoperative improvement of visual acuity was yielded in non-glaucoma patients (p<0.001); visual acuity outcome was worsen in glaucoma eyes. Conclusion Despite its rareness, early diagnosis and treatment of endophthalmitis is crucial for prognosis. In the present cohort, a worse visual acuity outcome was yielded in glaucoma patients in comparison to non-glaucoma patients.

Aspergillus Endophthalmitis: Epidemiology, Pathobiology, and Current Treatments

Fungal endophthalmitis is one of the leading causes of vision loss worldwide. Post-operative and traumatic injuries are major contributing factors resulting in ocular fungal infections in healthy and, more importantly, immunocompromised individuals. Among the fungal pathogens, the Aspergillus species, Aspergillus fumigatus, continues to be more prevalent in fungal endophthalmitis patients. However, due to overlapping clinical symptoms with other endophthalmitis etiology, fungal endophthalmitis pose a challenge in its diagnosis and treatment. Hence, it is critical to understand its pathobiology to develop and deploy proper therapeutic interventions for combating Aspergillus infections. This review highlights the different modes of Aspergillus transmission and the host immune response during endophthalmitis. Additionally, we discuss recent advancements in the diagnosis of fungal endophthalmitis. Finally, we comprehensively summarize various antifungal regimens and surgical options for the treatment of Aspergillus endophthalmitis.

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.

Emerging antimicrobial resistance and need for antimicrobial stewardship for ocular infections in India: A narrative review

Patients with ocular infections are at increased risk of vision impairment and may require immediate medical care to preserve their vision. Management of ocular bacterial infections has evolved in recent years and includes a pragmatic selection of broad-spectrum antibiotics based on the causative bacteria. Nevertheless, the treatment of bacterial ocular infections is increasingly becoming a challenge, as the causative bacterium acquires resistance to antibiotics through intrinsic and acquired methods. From an Indian perspective, along with the challenges of antibiotic resistance, there are other factors such as lack of knowledge on epidemiology, and lack of data on local susceptibility patterns of ocular pathogens that have significant impact on the management of ocular infections. This narrative review summarizes the available knowledge on prescribing antibiotics for five common ocular infections in India. It further highlights the significance of the understanding of antimicrobial susceptibility patterns across India as a cornerstone to promote rational use of ocular antibiotics. This review indicates that large-scale antimicrobial resistance surveillance studies can facilitate the synchronization of ophthalmic antimicrobial prescription policies with local antibiotic resistance patterns. Further, establishment of an antimicrobial stewardship program in ophthalmology can potentially increase the efficacy of diagnostic tools, and implement earlier adoption of effective antibiotics. Overall, this review provides consolidated information and key considerations for treatment decision-making of common ocular infections in India.

Postoperative Endophthalmitis After Cataract Surgery: An Update

Postoperative endophthalmitis is a serious complication that can happen after cataract surgery. It occurs mainly due to invasion of the globe by microbial flora, bacteria, or fungi from the adnexa and environment during the time of surgery. All patients undergoing cataract surgery should be evaluated for any potential risk factors that can enhance the development of postoperative endophthalmitis; managing the intraoperative risk and prophylaxis protocols should be considered in order to reduce the risk of endophthalmitis. Early follow-up after cataract surgery is highly recommended to detect any sign of endophthalmitis so as to treat it immediately and ensure patient compliance on post-surgery medication and precautions to reduce the serious complications caused by late diagnosis and treatment of post-cataract endophthalmitis.

Fungal Endophthalmitis: A Comprehensive Review

Endophthalmitis is a serious ophthalmologic condition involving purulent inflammation of the intraocular spaces. The underlying etiology of infectious endophthalmitis is typically bacterial or fungal. The mechanism of entry into the eye is either exogenous, involving seeding of an infectious source from outside the eye (e.g., trauma or surgical complications), or endogenous, involving transit of an infectious source to the eye via the bloodstream. The most common organism for fungal endophthalmitis is Candida albicans. The most common clinical manifestation of fungal endophthalmitis is vision loss, but other signs of inflammation and infection are frequently present. Fungal endophthalmitis is a clinical diagnosis, which can be supported by vitreous, aqueous, or blood cultures. Treatment involves systemic and intravitreal antifungal medications as well as possible pars plana vitrectomy. In this review, we examine these essential elements of understanding fungal endophthalmitis as a clinically relevant entity, which threatens patients’ vision.

Therapeutic Targeting of Inflammatory Pathways with Emphasis on NLRP3 Inflammasomes by Natural Products: A Novel Approach for the Treatment of Inflammatory Eye Diseases

There is an increase in the incidence of inflammatory eye diseases worldwide. Several dysregulated inflammatory pathways, including the NOD-like receptor protein 3 (NLRP3) inflammasome, have been reported to contribute significantly to the pathogenesis and progression of ophthalmic diseases. Although the available allopathic/conventional medicine has demonstrated effectiveness in managing eye diseases, there is an ongoing global demand for alternative therapeutics with minimal adverse drug reactions, easy availability, increase in patient-compliance, and better disease outcome. Therefore, several studies are investigating the utilization of natural products and herbal formulations in impeding inflammatory pathways, including the NLRP3 inflammasome, in order to prevent or manage eye diseases. In the present review, we highlight the recently reported inflammatory pathways with special emphasis on NLRP3 Inflammasomes involved in the development of eye diseases. Furthermore, we present a variety of natural products and phytochemicals that were reported to interfere with these pathways and their underlying mechanisms of action. These natural products represent potential therapeutic applications for the treatment of several inflammatory eye diseases.

FEATURES AND OUTCOMES OF EYES THAT UNDERWENT SURGICAL REPAIR OF RHEGMATOGENOUS RETINAL DETACHMENTS AFTER BEING TREATED FOR ACUTE ENDOPHTHALMITIS

PURPOSE

To evaluate the etiology, clinical course, and outcomes of eyes that suffered postendophthalmitis rhegmatogenous retinal detachments.

METHODS

A retrospective, consecutive case series was conducted of patients managed at Associated Retinal Consultants P.C. from January 2013 to December 2019. Patients were identified as having had endophthalmitis by ICD-9/10 codes. Those with endophthalmitis and/or rhegmatogenous retinal detachment not managed at Associated Retinal Consultants from January were excluded.

RESULTS

Charts of 413 patients were reviewed and 19 met inclusion criteria. Incidence of rhegmatogenous retinal detachment following infectious endophthalmitis was 4.6%. The most common inciting events for endophthalmitis was intravitreal injection (9 of 19) and cataract surgery (7 of 19). Fifteen of 19 patients were treated with an injection of intravitreal antibiotics and 4 underwent immediate vitrectomy with antibiotic injection. Biopsy cultures were obtained in 18 of 19 patients and yielded positive growth in 12 (66.7%). Seventeen of the 19 eyes were operable. Final retinal reattachment rate was 88.2% (15 of 17). Mean final logMAR visual acuity was 1.58 (Snellen 20/765). Factors associated with worse final visual acuity after surgical repair included preceding intravitreal injection (P = 0.001), streptococcus species (P = 0.024), presence of proliferative vitreoretinopathy (P = 0.015), and use of silicone oil during primary rhegmatogenous retinal detachment repair (P = 0.010).

CONCLUSION

Rhegmatogenous retinal detachments following endophthalmitis occur infrequently. Although most eyes can be repaired surgically, visual outcomes are often poor, particularly in eyes that were infected with streptococcal species and had associated proliferative vitreoretinopathy.

Macular and choroidal thickness after intracameral moxifloxacin for prevention of postcataract endophthalmitis

PURPOSE

To determine any changes in macular or choroidal thickness associated with the use of intracameral moxifloxacin as postcataract endophthalmitis prophylaxis.

SETTING

University of Campinas, Campinas, São Paulo, Brazil.

DESIGN

Prospective, randomized, partially masked, single-site clinical trial.

METHODS

Phacoemulsification surgery patients in the experimental group (Group A) received a 0.03 mL intracameral injection of undiluted moxifloxacin from a sealed bottle immediately after phacoemulsification surgery (150 μg in 0.03 mL-Vigamox solution), whereas the control group (Group B) did not. Investigators evaluated in masked fashion macular and choroidal thickness using spectral-domain optical coherence tomography preoperatively and postoperatively.

RESULTS

A total of 93 patients were included (48 in Group A and 45 in Group B). Baseline parameters were similar between the groups. Either of the 2 parameters assessed differed statistically between the groups or preoperatively vs postoperatively. On postoperative day 30, central macular thickness was 8.85 ± 14.78 μm in Group A and 10.26 ± 22.44 μm in Group B (P = .7232); choroidal thickness as measured by enhanced depth imaging (EDI) was 1.45 ± 16.13 μm in Group A and 3.74 ± 16.15 in Group B (P = .5017). On postoperative day 60, central macular thickness was 19.53 ± 39.28 μm in Group A and 17.14 ± 53.68 μm in Group B (P = .8363); EDI was 5.08 ± 21.96 μm in Group A and 5.24 ± 15.8 in Group B (P = .9752).

CONCLUSIONS

The application of intracameral injection of 0.03 mL of undiluted 0.5% moxifloxacin during phacoemulsification surgery as endophthalmitis prophylaxis induced no changes in macular or choroidal thickness.

A non-invasive nanoparticle-based sustained dual-drug delivery system as an eyedrop for endophthalmitis

Endophthalmitis is an infectious disease that affects the entire eye spreading to the internal retinal layers and the vitreous and causes severe sight-threatening conditions. Current treatment strategies rely on intraocular injections of antibiotics that are invasive, may lead to procedural complications and, ultimately, blindness. In this study, we developed a non-invasive strategy as an eyedrop containing nanoparticle-based dual-drug delivery system in which the hydrophobic poly-L-lactide core was loaded with azithromycin or triamcinolone acetonide, and the hydrophilic shell was made of chitosan. The developed nanoparticles were ~200-250 nm in size, spherical in shape, moderately hydrophilic, lysozyme tolerant, cytocompatible, and hemocompatible. Application of these chitosan-coated nanoparticles as eye drops to C57BL/6 mice showed higher bioavailability in choroid and retina when compared to the uncoated nanoparticles. The delivery system showed sustained release of drug for 300 h and exhibited antimicrobial effects against Gram-positive and Gram-negative bacteria and anti-inflammatory effects on activated microglial cells. Interestingly, the combination of the nanoparticles loaded with azithromycin and the nanoparticles loaded with triamcinolone acetonide acted synergistically as compared to either of the nanoparticles/drugs alone. Overall, the developed dual-drug delivery system is non-invasive, has antimicrobial and anti-inflammatory effects, and shows potential as an eye drop formulation against endophthalmitis.

The complement system in age-related macular degeneration

Age-related macular degeneration (AMD) is a chronic and progressive degenerative disease of the retina, which culminates in blindness and affects mainly the elderly population. AMD pathogenesis and pathophysiology are incredibly complex due to the structural and cellular complexity of the retina, and the variety of risk factors and molecular mechanisms that contribute to disease onset and progression. AMD is driven by a combination of genetic predisposition, natural ageing changes and lifestyle factors, such as smoking or nutritional intake. The mechanism by which these risk factors interact and converge towards AMD are not fully understood and therefore drug discovery is challenging, where no therapeutic attempt has been fully effective thus far. Genetic and molecular studies have identified the complement system as an important player in AMD. Indeed, many of the genetic risk variants cluster in genes of the alternative pathway of the complement system and complement activation products are elevated in AMD patients. Nevertheless, attempts in treating AMD via complement regulators have not yet been successful, suggesting a level of complexity that could not be predicted only from a genetic point of view. In this review, we will explore the role of complement system in AMD development and in the main molecular and cellular features of AMD, including complement activation itself, inflammation, ECM stability, energy metabolism and oxidative stress.

Effect of Taping Face Masks on Quantitative Particle Counts Near the Eye: Implications for Intravitreal Injections in the COVID-19 Era

Purpose

To determine the effect of taping the top of face masks on air particle counts directed toward the eye during simulated intravitreal injections.

Design

Prospective observational crossover study.

Methods

Thirteen healthy subjects were recruited. Each wore a cloth, surgical, or N95 mask in randomized order. The number of air particles were quantified by using a particle counter suspended over the right eye while each subject breathed normally, deeply, or spoke using a standardized script. Particle counts were obtained with the top of each mask taped and not taped. The main outcome measurements were particle counts of 0.3, 0.5, 1, 3, 5, and 10 μm and total particle counts.

Results

Taping cloth masks while subjects were speaking significantly reduced particle counts for the 0.3- (P = .03), 0.5- (P = .01), and 1-μm (P = .03) particles and total particle counts (P = .008) compared to no taping. Taping the top of cloth masks during normal or deep breathing did not significantly affect particle counts compared to no taping. Taping the top of surgical or N95 masks did not significantly alter particle counts for any breathing condition tested.

Conclusions

Taping the top of cloth masks prior to simulated intravitreal injections significantly reduced air particle counts directed toward the eye when subjects were speaking compared to no taping. This may have implications for decreasing air particles reaching the eye during intravitreal injections, including aerosolized droplets from a patient's mouth that may carry oral pathogens.

Intraocular lenses as drug delivery devices

Cataract surgery is one of the most common and safe surgical procedures nowadays. However, it is not free of risks as endophthalmitis, ocular inflammation and posterior capsule opacification (PCO) can appear as post-surgery complications. The usual eye drop therapy used as prophylaxis for the former two complications has limited bioavailability. In turn, the prevention of PCO involves an adequate surgical technique and a careful choice of intraocular lens (IOL) design and material. Also, different drugs have been tested to reduce incidence of PCO, but no prophylaxis demonstrated to be completely effective. In the past few years, IOLs have been proposed as drug delivery devices to replace or/assist the usual eye drop therapy in the post-operatory period. The great advantage of drug loaded IOLs would be to ensure a continuous drug delivery, independent of patient's compliance without requiring any further action besides IOL implantation. The biggest challenge of drug loaded IOLs production is to achieve a controlled and extended release that meet therapeutic needs without inducing toxicity to the surrounding ocular tissues or affecting the physical properties of the lens. This review starts by addressing the possible complications after cataract surgery, as well as the most commonly adopted prophylaxis for each of them. The various types of IOLs are described and their main advantages/disadvantages are discussed. The different strategies pursued to incorporate drugs into the IOLs and control their release, which include soaking the IOL in the drugs solution, supercritical impregnation, surface modifications, and attachment of drug reservoirs to the IOL, among others, are reported. For each strategy, a summary of the publications is presented, which includes the target complication, the types and amounts of released drugs and the IOL materials. A brief description of each individual study is given afterwards. Optimization of drug loaded IOLs through mathematical modelling and possible issues raised by their sterilization are also tackled. At the end, the future commercialization of drug loaded IOLs is commented.

Diagnostic value of culture results from aqueous tap versus vitreous tap in cases of bacterial endophthalmitis

OBJECTIVE

To investigate the concordance between aqueous and vitreous tap culture results among different types of bacterial endophthalmitis.

METHODS AND ANALYSIS

This retrospective cohort analysis included all cases diagnosed with endophthalmitis at Moorfields Eye Hospital between January 2008 and March 2020. Aqueous and vitreous samples obtained simultaneously at presentation. Samples were evaluated for sensitivity, specificity, negative and positive predictive values.

RESULTS

A total of 217 patients (217 eyes) were included in the study. Postsurgical endophthalmitis was the most common type of endophthalmitis and diagnosed in 35.9% of the cases. The rate of positive culture results was 32.2% from vitreous tap and 21.7% from aqueous tap. The culture yield through vitreous sampling was 15.7% when aqueous culture results were negative, and in 5.1%, the aqueous sample was positive when the vitreous tap results were negative. Considering the vitreous tap as the gold standard, aqueous sample culture results showed a statistically significant high specificity and positive predictive values in cases of postsurgical endophthalmitis, late-onset endophthalmitis associated with glaucoma procedures, postintravitreal injection and endophthalmitis associated with bacterial keratitis. Coagulase Negative Staphylococcus was the most common organism isolated from vitreous and aqueous samples.

CONCLUSIONS

Even though the sensitivity and specificity of aqueous tap are low, our results show that in a few cases it identified important organisms, otherwise missed by vitreous sampling alone. Culture of vitreous sample remains the gold standard for isolation of pathogen in bacterial endophthalmitis, but aqueous samples should also be obtained as an adjunct for the diagnosis.

Clarithromycin Solid Lipid Nanoparticles for Topical Ocular Therapy: Optimization, Evaluation and In Vivo Studies

Solid lipid nanoparticles (SLNs) are being extensively exploited as topical ocular carrier systems to enhance the bioavailability of drugs. This study investigated the prospects of drug-loaded SLNs to increase the ocular permeation and improve the therapeutic potential of clarithromycin in topical ocular therapy. SLNs were formulated by high-speed stirring and the ultra-sonication method. Solubility studies were carried out to select stearic acid as lipid former, Tween 80 as surfactant, and Transcutol P as cosurfactant. Clarithromycin-loaded SLN were optimized by fractional factorial screening and 3² full factorial designs. Optimized SLNs (CL10) were evaluated for stability, morphology, permeation, irritation, and ocular pharmacokinetics in rabbits. Fractional factorial screening design signifies that the sonication time and amount of lipid affect the SLN formulation. A 3² full factorial design established that both factors had significant influences on particle size, percent entrapment efficiency, and percent drug loading of SLNs. The release profile of SLNs (CL9) showed ~80% drug release in 8 h and followed Weibull model kinetics. Optimized SLNs (CL10) showed significantly higher permeation (30.45 μg/cm²/h; p < 0.0001) as compared to control (solution). CL10 showed spherical shape and good stability and was found non-irritant for ocular administration. Pharmacokinetics data demonstrated significant improvement of clarithromycin bioavailability (p < 0.0001) from CL10, as evidenced by a 150% increase in C_max (~1066 ng/mL) and a 2.8-fold improvement in AUC (5736 ng h/mL) (p < 0.0001) as compared to control solution (C_max; 655 ng/mL and AUC; 2067 ng h/mL). In summary, the data observed here demonstrate the potential of developed SLNs to improve the ocular permeation and enhance the therapeutic potential of clarithromycin, and hence could be a viable drug delivery approach to treat endophthalmitis.

Incidence of Endophthalmitis after Intravitreal Anti-Vascular Endothelial Growth Factor Injections in an Operating Room in China

Purpose

To evaluate the rate of presumed endophthalmitis (EO) after intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections performed in an operating room (OR) under sterile conditions in mainland China.

Methods

Retrospective single-center study between September 2012 and December 2017 at Beijing Tongren Eye Center, Beijing, China. Intravitreal injection database was reviewed. All anti-VEGF injections were performed using a standardized sterile technique in an OR. Injection protocols included antibiotics for 3 days pre-injection, topical 5% povidone-iodine rinsing before the procedure, and post-injection antibiotics for 3 days.

Results

A total of 37,830 intravitreal injections were performed at Beijing Tongren Eye Center. Three cases were managed as presumed EO (0.0079%). Positive cultures were documented in 2 of 3 cases. EO incidence following ranibizumab and conbercept administration was 0.0088% (3 in 33,930) and 0% (0 in 3,900), respectively. No significant difference was detected between the two drugs (P = 0.745).

Conclusions

Very low EO rates were seen in mainland China using a standardized sterile technique in an OR. However, EO could not be completely avoided.

Endophthalmitis After Descemet Stripping Endothelial Keratoplasty: Microbiological Yield and Visual Outcomes

PURPOSE

To describe the clinical presentation, management, and visual outcomes of 6 eyes with endophthalmitis after Descemet stripping endothelial keratoplasty (DSEK).

DESIGN

Retrospective case series.

METHODS

Setting: Tertiary, academic eye center. StudyPopulation: Individuals developing endophthalmitis after DSEK at the Duke Eye Center from January 1, 2009, to January 1, 2018, with at least 6 months of follow-up. ObservationProcedure: Retrospective chart review. OutcomeMeasures: Diagnostic procedures, microbiological yield, and visual outcomes.

RESULTS

Six eyes of 6 patients were identified. Mean time from surgery to presentation was 51 days (range, 4-137 days). Dense vitreous opacities were present in all cases. Five of 6 cases (83%) had culture-proven infectious endophthalmitis (2 Candida glabrata, 2 coagulase-negative Staphylococcus, 1 Streptococcus pneumoniae). Aqueous tap yielded positive culture in 2 of 2 cases with adequate sample (100%); needle vitreous tap yielded positive culture in 0 of 3 cases. One eye underwent vitrectomy on presentation, and 3 eyes (50%) underwent subsequent vitrectomy for persistent endophthalmitis after a mean of 37 days. Mean pre-endophthalmitis visual acuity (VA) was 20/64; mean VA at 6 months was 20/2069 (average 15 ETDRS lines lost). VA at 6 months was light perception or no light perception in 3 of 6 cases (50%). One eye underwent enucleation at 6 months, and 1 eye became phthisical 1 year after endophthalmitis.

CONCLUSIONS

DSEK-related endophthalmitis may lead to severe vision loss, even with prompt and appropriate treatment. Aqueous tap had a higher culture yield than needle vitreous tap in our series.

The ocular surface bacterial contamination and its management in the prophylaxis of post cataract surgery endophthalmitis

Objective: To investigate the recent pieces of evidence regarding the bacterial ocular surface contamination and its treatment in the prophylaxis of post-cataract surgery endophthalmitis. Methods: We conducted a literature research on the topic of interest and selected the most relevant data. Results: The studies reported a relatively high rate of positive conjunctival culture and the most frequently isolated organism was Coagulase negative Staphylococcus, which is also the most common etiological agent of the postoperative endophthalmitis. The bacterial ocular surface load is influenced by age, climate, associated diseases, topical and systemic medication. The use of povidone-iodine alone or in association with levofloxacin eyedrops as prophylactic method is effective in reducing the conjunctival bacterial contamination and consequently decreases the incidence of postoperative endophthalmitis. Conclusions: Based on the current pieces of evidence, adequate treatment of the bacterial ocular surface contamination prior to cataract surgery seems to be effective in preventing endophthalmitis after cataract surgery. Abbreviations: EU = European Union, Spp. = Species, HIV = Human Immunodeficiency Virus.

Endophthalmitis in Oman: A descriptive retrospective multi-center study

PURPOSE:

The aim of this study is to report the anatomical and functional outcome, microbiology profile and treatment used for endophthalmitis in Oman.

DESIGN:

The study design involves retrospective descriptive multicenter study.

METHODS:

Demographic and clinical data of patients diagnosed with endophthalmitis over a period of 9 years were collected in three tertiary hospitals in Oman.

RESULTS:

A total of 50 endophthalmitis cases were included in the study. Exogenous endophthalmitis was diagnosed in 48 cases, whereas 2 cases were endogenous endophthalmitis. Culture-positive cases constituted 16 cases (32%) out of these, 12 cases were Gram-positive, 3 cases were Gram-negative and one case had a positive fungal culture. Immediate first-line treatment was vitreous tap and inject in 33 eyes and vitrectomy in 13 eyes. In 45 eyes in which the visual acuity (VA) was recorded; VA after treatment improved in 22 eyes (49%), remained the same in 16 eyes (36%) and worsened in 7 eyes (16%).

CONCLUSION:

Although endophthalmitis is rare, it is a devastating ocular emergency. Early diagnosis and prompt intervention are crucial in management. Awareness among the patients undergoing intraocular surgeries about this rare condition is very crucial. Moreover, frontline health-care providers must be aware and critical if they encounter patients with suspicion of endophthalmitis as early recognition, prompt referral, and timely treatment are the key for better visual prognosis. Finally, establishing a National Endophthalmitis Registry is recommended as it will help analyze the incidence, treatment instituted and the outcome of this condition across Oman.

Antibacterial Nanopillar Array for an Implantable Intraocular Lens

Postsurgical intraocular lens (IOL) infection caused by pathogenic bacteria can result in blindness and often requires a secondary operation to replace the contaminated lens. The incorporation of an antibacterial property onto the IOL surface can prevent bacterial infection and postoperative endophthalmitis. This study describes a polymeric nanopillar array (NPA) integrated onto an IOL, which captures and eradicates the bacteria by rupturing the bacterial membrane. This is accomplished by changing the behavior of the elastic nanopillars using bending, restoration, and antibacterial surface modification. The combination of the polymer coating and NPA dimensions can decrease the adhesivity of corneal endothelial cells and posterior capsule opacification without causing cytotoxicity. An ionic antibacterial polymer layer is introduced onto an NPA using an initiated chemical vapor deposition process. This improves bacterial membrane rupture efficiency by increasing the interactions between the bacteria and nanopillars and damages the bacterial membrane using quaternary ammonium compounds. The newly developed ionic polymer-coated NPA exceeds 99% antibacterial efficiency against Staphylococcus aureus, which is achieved through topological and physicochemical surface modification. Thus, this paper provides a novel, efficient strategy to prevent postoperative complications related to bacteria contamination of IOL after cataract surgery.

Infectious endophthalmitis at a Philippine tertiary hospital: a ten-year retrospective study

Background

Endophthalmitis is a sight-threatening disease characterized by marked progressive inflammation of the vitreous and/or aqueous humors. Limited information is currently available regarding endophthalmitis in the Philippines. This study aimed to provide long-term summary data on endophthalmitis cases seen at the largest tertiary referral hospital in the Philippines.

Methods

All endophthalmitis cases diagnosed at the Philippine General Hospital from January 1, 2007 to December 31, 2016 were retrieved and classified by etiology. Data pertaining to history, associated risk factors, isolated microorganisms, management, and final visual outcomes for each patient were reviewed.

Results

A total of 202 cases diagnosed within the audit period were included in the study. These were classified as post-traumatic (55.94%), endogenous (14.36%), acute post-operative (10.40%), keratitis-induced (6.93%), chronic post-operative (5.44%), bleb-associated (3.96%), and suture-associated (2.97%) endophthalmitis. Males comprised 71.29% of the population, while the largest age group affected was 0–10 years (24.75%). The culture-positive rate was 57.89%. The predominant etiology was Gram-positive bacteria (38.18%), followed by Gram-negative bacteria and mixed pathogens (21.82% each), and fungi (18.18%). The most common organisms were Streptococcus, Staphylococcus, Pseudomonas, Aspergillus, and Candida, accounting for 56.45% of isolates. Pars plana vitrectomy was done for 62.87% of patients, intravitreal and other antibiotic therapy in 23.27%, and primary enucleation/evisceration in 10.89%. The final outcomes and best corrected visual acuities were: anophthalmia 11.86%, no light perception/no dazzle 27.84%, light perception 8.76%, hand motions 24.23%, counting fingers 5.15%, 3/200 to 20/50 12.89%, and 20/40 to 20/20 9.28%.

Conclusions

There was a higher proportion of post-traumatic endophthalmitis cases compared to traditional estimates but consistent with studies from China and Thailand. The majority of these cases involved younger children as well as young to middle-aged males engaged in carpentry and construction work, implying a need for increased public health awareness and strengthening of childcare and workplace safety policies. Our microbiologic profile showed a lower proportion of Gram-positive infections and a higher proportion of mixed pathogen infections compared to other studies. There was also a higher proportion of fungi associated with post-operative and keratitis-induced endophthalmitis. The best outcomes were seen in acute post-operative and bleb-associated endophthalmitis, and the worst outcomes in endogenous and keratitis-induced endophthalmitis. Visual outcomes were poorer compared to other Western and Asian countries, with only 21.7% of patients improving from presentation.

Time to Presentation after Symptom Onset in Endophthalmitis: Clinical Features and Visual Outcomes

PURPOSE

To investigate the impact of time from symptom onset to presentation on the clinical course and outcomes of eyes with endophthalmitis.

DESIGN

Retrospective, longitudinal cohort study.

PARTICIPANTS

One hundred thirty-three eyes of 130 patients with endophthalmitis.

METHODS

Adults diagnosed with endophthalmitis at the Duke Eye Center from January 1, 2009, through January 1, 2018, were identified using the Duke Enterprise Data Unified Content Explorer. Patient demographics, time of symptom onset, presenting clinical features, management, and outcomes were recorded by retrospective review. Patients were divided into those seeking medical care either early (within 2 days) or later (delayed, i.e., 3 days or longer) with regard to symptom onset. Clinical features, management, and visual outcomes of eyes with early or delayed presentation were compared.

MAIN OUTCOME MEASURES

Mean corrected visual acuity (VA) at presentation and at 6 months.

RESULTS

In eyes with delayed presentation, VA was significantly worse on initial examination (delayed, 20/2941 vs. early, 20/1124; P = 0.009) and at 6 months (delayed, 20/547 vs. early, 20/173; P = 0.01). When controlling for time to presentation, VA before endophthalmitis was correlated significantly with VA at 6 months (Pearson r = 0.55; R² = 29%; P < 0.0001). Eyes with glaucoma drainage device-related endophthalmitis were more likely to have a delayed presentation (P = 0.03). Eyes with delayed presentation were more likely to have conjunctival injection on initial examination (delayed, 73% vs. early, 52%; P = 0.01). Visual acuity before endophthalmitis, pain, and patient-reported blurred vision were not associated with early or delayed presentation (P > 0.05).

CONCLUSIONS

Delayed presentation was associated with worse VA on initial examination and at 6 months in eyes with endophthalmitis. Presence of pain did not prompt earlier presentation. Visual acuity before endophthalmitis was associated with VA at 6 months, regardless of time to presentation. Further investigation may help to improve anticipatory guidelines for at-risk patients.

Risk Factors for Post–Open-Globe Injury Endophthalmitis

Purpose:

The objective of our project is to use the National Inpatient Sample Database to identify risk factors for endophthalmitis in cases of open-globe injury (OGI).

Methods:

This is a cross-sectional observational study of 48 627 cases of OGI from the National Inpatient Sample Database. We performed regression analysis using IBM SPSS Statistics 23. Codes from the International Classification of Disease, Ninth Revision were used to identify ocular findings and conditions. Variables with P values less than .05 on univariate analysis were included in the multivariable regression model; Bonferroni correction was applied to these results.

Results:

Of the 48 627 cases of OGI, 37 440 (77.0%) occurred in the adult group (21 years and older). Overall, 1018 (2.1%) cases developed posttraumatic endophthalmitis, with 74.5% cases in the adult group. Endophthalmitis developed in 293 (4.5%) eyes with an intraocular foreign body (IOFB). Results of binary logistic regression showed the clinical findings of traumatic cataracts, hypopyon, vitreous inflammation, corneal ulcers, or IOFBs were associated with an increased risk of developing endophthalmitis after OGI. Conversely, orbital fractures, rupture-type injuries, and intraocular tissue prolapse were associated with a decreased likelihood of being diagnosed with endophthalmitis.

Conclusions:

Endophthalmitis developed in 2.4% of pediatric OGIs and 2.0% of adult OGIs. Traumatic cataract, hypopyon, vitreous inflammation, corneal ulcer, keratitis, retinal detachment, IOFB, and diabetes increased the risk of post-open-globe endophthalmitis.

Clinical Etiologies, Microbial Spectrum, Antibiotic Susceptibilities, and Visual Acuity Outcomes of Acute Endophthalmitis

Purpose: The purpose of this study was to report the clinical etiologies, microbial spectrum, antibiotic resistance, and visual acuity (VA) outcomes associated with acute endophthalmitis. Methods: A retrospective chart review of patients with International Classification of Diseases (ICD)-9 and ICD-10 codes for endophthalmitis over a 6-year period (2011-2016) at a tertiary referral center was performed. The clinical records were reviewed to evaluate clinical etiologies, microbial spectrum, antibiotic susceptibilities and resistance, and visual outcomes. Results: Medical records of 94 patients treated for culture-proven endophthalmitis were reviewed. The etiologies of endophthalmitis were exogenous in 68.8% of cases and endogenous in 31.2% of cases. The most common inciting factors for exogenous endophthalmitis were progression of corneal ulcer and postoperative infection after cataract extraction. The microbial spectrum of causative organisms was dominated by coagulase-negative Staphylococcus (30.9%), followed by Staphylococcus aureus (23.4%). The most frequent fungal isolates were Candida species. Antibiotic susceptibilities of gram-positive bacteria ranged from 96.7% for vancomycin to 28.8% for penicillin G. Antibiotic susceptibilities of gram-negative bacteria were overall very high, with >90% susceptibility among isolated culture samples. Final VA outcomes of 20/400 or better were reported in 62.5% of patients. Conclusions: The study demonstrates that the most frequent clinical etiology of endophthalmitis was exogenous due to progression of corneal ulcer and postoperative infection after cataract extraction. The spectrum of pathogens causing endophthalmitis is composed of mainly Gram-positive organisms (particularly coagulase-negative Staphylococcus). VA was improved in the majority of patients after treatment for endophthalmitis.

The cereus matter of Bacillus endophthalmitis

Bacillus cereus (B. cereus) endophthalmitis is a devastating intraocular infection primarily associated with post-traumatic injuries. The majority of these infections result in substantial vision loss, if not loss of the eye itself, within 12-48 h. Multifactorial mechanisms that lead to the innate intraocular inflammatory response during this disease include the combination of robust bacterial replication, migration of the organism throughout the eye, and toxin production by the organism. Therefore, the window of therapeutic intervention in B. cereus endophthalmitis is quite narrow compared to that of other pathogens which cause this disease. Understanding the interaction of bacterial and host factors is critical in understanding the disease and formulating more rational therapeutics for salvaging vision. In this review, we will discuss clinical and research findings related to B. cereus endophthalmitis in terms of the organism's virulence and inflammogenic potential, and strategies for improving of current therapeutic regimens for this blinding disease.

Noncompliance with Prescribed Eyedrop Regimens Among Patients Undergoing Cataract Surgery—Prevalence, Consequences, and Solutions

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