Specific PCR and Quantitative Real-Time PCR in Ocular Samples from Acute and Delayed-Onset Postoperative Endophthalmitis

Intravitreal Antibiotics versus Early Vitrectomy Plus Intravitreal Antibiotics for Postinjection Endophthalmitis: An IRIS® (Intelligent Research in Sight Registry) Analysis

PURPOSE

To determine if intravitreal injection of antibiotics alone versus early pars plana vitrectomy (PPV) plus injection of intravitreal antibiotics predicted better or worse visual outcomes for patients with endophthalmitis after anti-VEGF injections.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients developing endophthalmitis after receiving an intravitreal anti-VEGF injection from the American Academy of Ophthalmology IRIS® (Intelligent Research in Sight) Registry between 2016 and 2020.

METHODS

Inclusion criteria were endophthalmitis diagnosis within 1 to 28 days after anti-VEGF injection and a recorded visual acuity (VA) at baseline, on the day of diagnosis, and posttreatment. Patients in the Injection Only group underwent intravitreal injection of antibiotics alone and in the Early Vitrectomy group received PPV with intravitreal antibiotics or intravitreal injection followed by PPV within 2 days of diagnosis. Patients were excluded if they had cataract surgery during the study, intravitreal steroids before endophthalmitis, or intermediate/posterior uveitis or cystoid macular edema. The study created a 1:1 matched cohort using Mahalanobis distance matching, accounting for the differences in VA at baseline and diagnosis.

MAIN OUTCOME MEASURES

Posttreatment logarithm of the minimum angle of resolution (logMAR) VA.

RESULTS

A total of 1044 patients diagnosed with postinjection endophthalmitis met the inclusion and exclusion criteria. In the unmatched cohort, there were 935 patients in the Injection Only and 109 in the Early Vitrectomy group. In 1:1 matched cohort, 218 patients (109 in each group) were included; the median logMAR VAs were 0.32 (20/40-20/50) at baseline, 0.88 (∼20/150) at diagnosis, and 0.57 (20/70-20/80) posttreatment. There were no statistically significant differences in the visual outcomes between the 2 matched treatment groups (b = 0.05; P = 0.23); including the subgroup of patients with VA worse than 1.0 logMAR (b = 0.05; P = 0.452).

CONCLUSIONS

There was no significant difference in final VA outcomes between patients receiving Injection Only and those treated with Early Vitrectomy for postinjection endophthalmitis. The findings support the use of either treatment strategy.

FINANCIAL DISCLOSURE(S)

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

The diagnosis and treatment progress of infectious endophthalmitis

Endophthalmitis is a blinding disease that may lead to permanent vision loss. The diagnosis of endophthalmitis relies on clinical findings. It is crucial to identify causative microorganisms in time for subsequent treatment and saving vision. For a long time, cultures of vitreous and/or aqueous humours have been the gold standard for the diagnosis of endophthalmitis. The development of modern molecular diagnostic techniques has brought new opportunities for identifying pathogens rapidly and improving sensitivity. Intravitreal antibiotic injection has the become standard treatment option for infectious endophthalmitis in clinical practice, however, the role and timing of pars plana vitrectomy remains controversial. Moreover, the development of new drugs for intravitreal injection and posterior segment drug delivery systems is expected to achieve the transition from invasive to non-invasive management. Thus, endophthalmitis is an ophthalmic emergency and timely diagnosis and treatment are crucial for preserving vision.

Rapid, multiplex and automated detection of bacteria and fungi in endophthalmitis via a microfluidic real-time pcr system

BACKGROUND

Endophthalmitis is an ophthalmologic emergency requiring accurate and rapid diagnosis for treatment. Currently, the diagnosis commonly relies on culture and molecular biology, which falls short of clinical rapid diagnosis. The purpose of this study was to evaluate the feasibility of a self-build Microfluidic Real-time Polymerase Chain Reaction (RT-PCR) System for rapidly identifying potential pathogens of endophthalmitis.

METHODS

This study included 22 patients who presented to Shenzhen Eye Hospital and the Ophthalmology Department of the Affiliated Hospital of Guizhou Medical University in China between January 2023 and March 2024. The samples were cultured using conventional methods and underwent Microfluidic RT-PCR and metagenomic next-generation sequencing (mNGS).

RESULTS

The Microfluidic RT-PCR System identified pathogens in 11 of 22 cases (50.00%), compared with 40.91% for microbiology culture. 14 cases (63.64%) had concordant results, and 5 cases were positive for the microfluidic system only. The agreements between culture and microfluidic system, as well as culture and mNGS were 100.00% (6/6) and 50.00% (3/6), respectively. The average waiting time for the microfluidic system was about 30 min if excepting DNA extraction time, which was much shorter than 2.88 days for culture and 1.57 days for mNGS.

CONCLUSION

The microfluidic-based RT-PCR system was preliminarily proved to be a sensitive, easy-to-operate, and rapid in-hospital technology. It is expected to become a rapid diagnostic platform for endophthalmitis.

Comparison of the aetiology, microbiological isolates and antibiotic susceptibilities of endophthalmitis between children and adults in southern China: a retrospective, cohort study

OBJECTIVES

To compare aetiology, microbiological isolates and antibiotic susceptibilities of endophthalmitis between children and adults.

DESIGN

Retrospective observational study.

PARTICIPANTS

Patients admitted to Zhongshan Ophthalmic Center between January 2013 and December 2019 with clinically diagnosed endophthalmitis were included.

OUTCOME MEASURES

The aetiology, microbiological isolates and antibiotic susceptibilities of endophthalmitis were analysed.

RESULTS

Of 1803 patients, 430 (23.8%) were aged ≤16 years. In both children and adults, the main aetiology was trauma (85.6% vs 64.7%, p<0.05). Streptococcus species (spp.) (28.8%) were most prevalent in paediatric post-traumatic endophthalmitis; whereas, coagulase-negative staphylococci (36.9%) were dominant in adults. In postoperative endophthalmitis, all children had bacterial infections, while fungal infections accounted for 12.5% in adults. In endogenous endophthalmitis caused by fungi, Candida was most prevalent in adults (26.9%); whereas, all causative fungi involved filamentous fungi in children. Isolated bacteria in children presented a higher susceptibility in 7 of 11 antibiotics compared with those in adults. Levofloxacin had the highest susceptibility rate in children (97.9%), and ofloxacin had the highest susceptibility rate in adults (90.6%).

CONCLUSION

The main aetiology was trauma, with a higher proportion in children than in adults. The microbial profile of paediatric endophthalmitis was different from those of adults. Susceptibilities of causative bacteria to most antibiotics were higher in children than in adults.

Using Electronic Health Record Data to Determine the Safety of Aqueous Humor Liquid Biopsies for Molecular Analyses

Purpose

Knowing the surgical safety of anterior chamber liquid biopsies will support the increased use of proteomics and other molecular analyses to better understand disease mechanisms and therapeutic responses in patients and clinical trials. Manual review of operative notes from different surgeons and procedures in electronic health records (EHRs) is cumbersome, but free-text software tools could facilitate efficient searches.

Design

Retrospective case series.

Participants

A total of 1418 aqueous humor liquid biopsies from patients undergoing intraocular surgery.

Methods

Free-text EHR searches were performed using the Stanford Research Repository cohort discovery tool to identify complications associated with anterior chamber paracentesis and subsequent endophthalmitis. Complications of the surgery unrelated to the biopsy were not reviewed.

Main Outcome Measures

Biopsy-associated intraoperative complications and endophthalmitis.

Results

A total of 1418 aqueous humor liquid biopsies were performed by 17 experienced surgeons. EHR free-text searches were 100% error-free for surgical complications, >99% for endophthalmitis (<1% false positive), and >93.6% for anesthesia type, requiring manual review for only a limited number of cases. More than 85% of cases were performed under local anesthesia without ocular muscle akinesia. Although the most common indication was cataract (50.1%), other diagnoses included glaucoma, diabetic retinopathy, uveitis, age-related macular degeneration, endophthalmitis, retinitis pigmentosa, and uveal melanoma. A 50- to 100-μL sample was collected in all cases using either a 30-gauge needle or a blunt cannula via a paracentesis. The median follow-up was >7 months. There was only one minor complication (0.07%) identified: a case of a small tear in Descemet membrane without long-term sequelae. No other complications occurred, including other corneal injuries, lens or iris trauma, hyphema, or suprachoroidal hemorrhage. There was no case of postoperative endophthalmitis.

Conclusions

Anterior chamber liquid biopsy during intraocular surgery is a safe procedure and may be considered for large-scale collection of aqueous humor samples for molecular analyses. Free-text EHR searches are an efficient approach to reviewing intraoperative procedures.

Financial Disclosures

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

Risk Factors for Legal Blindness in 237 Japanese Patients with Exogenous Endophthalmitis: A Multicenter Cohort Study from J-CREST

PURPOSE

We investigated potential risk factors for visual prognosis in Japanese patients with exogenous endophthalmitis.

METHODS

In this retrospective observational multicenter cohort study, risk factors for legal blindness at 12 weeks after treatment initiation were evaluated based on patient characteristics, initial BCVA, causative events, pathogens, ocular symptoms, duration from symptom onset to initial treatment, and selected treatments.

RESULTS

Overall, 23.1% of eyes developed legal blindness. The six risk factors for legal blindness were presence of eye pain, pathogen identification, poor BCVA at the initial visit, longer duration from symptom onset to initial treatment, type of causative event, and type of causative pathogen. Regarding the type of causative pathogen, coagulase-negative staphylococci was associated with a better visual impairment outcome.

CONCLUSION

Exogenous endophthalmitis remains a severe ocular infection; however, it can be managed with rapid treatment, as well as other advances in medical knowledge and technology.

Utility of pan-bacterial and pan-fungal PCR in endophthalmitis: case report and review of the literature

BACKGROUND

Endophthalmitis is a clinical diagnosis but identification of the disease-causing agent or agents allows for a more tailored treatment. This is routinely done through intraocular fluid cultures and staining. However, culture-negative endophthalmitis is a relatively common occurrence, and a causative organism cannot be identified. Thus, further diagnostic testing, such as pan-bacterial and pan-fungal polymerase chain reactions (PCRs), may be required. BODY: There are now newer, other testing modalities, specifically pan-bacterial and pan-fungal PCRs, that may allow ophthalmologists to isolate a causative agent when quantitative PCRs and cultures remain negative. We present a case report in which pan-fungal PCR was the only test, amongst quantitative PCRs, cultures, and biopsies, that was able to identify a pathogen in endophthalmitis. Pan-PCR has unique advantages over quantitative PCR in that it does not have a propensity for false-positive results due to contamination. Conversely, pan-PCR has drawbacks, including its inability to detect viruses and parasites and its increased turnaround time and cost. Based on two large retrospective studies, pan-PCR was determined not to be recommended in routine cases of systemic infection as it does not typically add value to the diagnostic workup and does not change the treatment course in most cases. However, in cases like the one presented, pan-bacterial and pan-fungal PCRs may be considered if empiric treatment fails or if the infective organism cannot be isolated. If pan-PCR remains negative or endophthalmitis continues to persist, an even newer form of testing, next-generation sequencing, may aid in the diagnostic workup of culture-negative endophthalmitis.

CONCLUSION

Pan-bacterial and pan-fungal PCR testing is a relatively new diagnostic tool with unique advantages and drawbacks compared to traditional culturing and PCR methods. Similar to the tests' use in non-ophthalmic systemic infections, pan-bacterial and pan-fungal PCRs are unlikely to become the initial diagnosis test and completely replace culture methods. However, they can provide useful diagnostic information if an infectious agent is unable to be identified with traditional methods or if empiric treatment of endophthalmitis continues to fail.

Evaluation of Outcomes of Acute Cataract Surgery-Related Endophthalmitis Using a Novel Management Algorithm Based on Presenting Risk Factors

PURPOSE

Develop treatment algorithm for acute endophthalmitis (AE) following cataract surgery.

METHODS

Retrospective single-center, non-randomized interventional study involving patients with AE divided into cohorts according to our novel scoring system, the Acute Cataract surgery-related Endophthalmitis Severity (ACES) score. Total score ≥3 points indicated need for urgent pars plana vitrectomy (PPV; within 24 hours), whereas <3 points indicated urgent PPV was unnecessary. Patients were retrospectively evaluated for visual outcomes based on whether their clinical course followed with or deviated from ACES score recommendations. Main outcome was best-corrected visual acuity (BCVA) at 6-month or longer after treatment.

RESULTS

Total of 150 patients were analyzed. Patients whose clinical course followed the ACES score recommendation for immediate surgery had significantly (P < 0.01) better final BCVA (median = 0.18 logMAR, 20/30 Snellen) compared to those that deviated (median = 0.70 logMAR, 20/100 Snellen). For those where the ACES score deemed urgent PPV was unnecessary, no significant (P = 0.19) difference was observed between patients that followed with (median = 0.18 logMAR, 20/30 Snellen) and those that deviated from (median = 0.10 logMAR, 20/25 Snellen) recommendation.

CONCLUSIONS

The ACES score may potentially provide critical and updated management guidance at presentation for when to recommend urgent PPV for patients suffering from post-cataract surgery AE.

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.

The diagnostic utility of nanopore targeted sequencing in suspected endophthalmitis

PURPOSE

This paper aimed to assess the diagnostic utility of a newly developed gene-based technology-nanopore targeted sequencing (NTS) in suspected endophthalmitis patients.

METHODS

This retrospective study included 43 patients (44 eyes) with suspected endophthalmitis. NTS was applied along with microbiological culture to detect unknown pathogens in intraocular fluid samples. The diagnostic utility of NTS was mainly evaluated from three aspects, including the positivity rate of bacterial/fungal presence, diagnostic turnaround time and the frequency of change in treatment based on etiology test results. Non-parametric, two-sided Wilcoxon rank sum test, the McNemar's test and the kappa statistic were used for statistical comparisons.

RESULTS

NTS showed significant advantages over traditional culture in positivity rates and diagnostic time (P < 0.001, kappa = 0.082; Z = -5.805, P < 0. 001). As regards antibiotic strategy, 17 patients (39.53%) and 5 patients (11.63%) underwent medication change following NTS and culture results respectively (P < 0.001, kappa = 0.335). With reasonable use of antibiotic and surgical intervention, most patients responded favorably, judged by significantly improved visual acuity (Z = -4.249, P < 0.001). The mean duration of hospitalization was 8.49 ± 2.45 days (range, 1-16 days).

CONCLUSION

The high efficiency feature of NTS in pathogen detection renders it a valuable supplementary to traditional culture. Additionally, it has facilitated patients' management for the early and precise diagnosis of endophthalmitis.

An All-in-One Highly Multiplexed Diagnostic Assay for Rapid, Sensitive, and Comprehensive Detection of Intraocular Pathogens

PURPOSE

Intraocular infections are sight-threatening conditions that can lead to vision loss. Rapid identification of the etiologies plays a key role in early initiation of effective therapy to save vision. However, current diagnostic modalities are time consuming and lack sensitivity and inclusiveness. We present here a newly developed comprehensive ocular panel designed to improve diagnostic yields and provide a tool for rapid and sensitive pathogen detection.

DESIGN

Experimental laboratory investigation.

METHODS

A panel containing 46 pathogens and 2 resistance/virulence markers that are commonly detected in intraocular infections was developed. Genomic targets were scrutinized for stretches predicted to be specific for a particular species while being conserved across different strains. A set of primers for sample enrichment, and two 50mer NanoString compatible probes were then designed for each target. Probe-target hybrids were detected and quantified using the NanoString nCounter SPRINT Profiler. Diagnostic feasibility was assessed in a pilot clinical study testing samples from infectious retinitis (n = 15) and endophthalmitis (n = 12) patients, for which the etiologies were confirmed by polymerase chain reaction (PCR) or culture.

RESULTS

Analytical studies demonstrated highly sensitive detection of a broad spectrum of pathogens, including bacteria, viruses, and parasites, with limits of detection being as low as 2.5 femtograms per reaction. We also found excellent target specificity, with minimal cross-reactivity detected. The custom-designed NanoString ocular panel correctly identified the causative agent from all clinical specimens positive for a variety of pathogens.

CONCLUSION

This highly multiplexed panel for pathogen detection offers a sensitive, comprehensive, and uniform assay run directly on ocular fluids that could significantly improve diagnostics of sight-threatening intraocular infections.

Role of Recent PCR Tests for Infectious Ocular Diseases: From Laboratory-Based Studies to the Clinic

Infectious uveitis is a vision-threatening condition that requires prompt clinical diagnosis and proper treatment. However, rapid and proper diagnosis in infectious uveitis remains challenging. Several examination tests, including polymerase chain reaction (PCR) tests, are transitioning from laboratory-based basic research-level tests to bedside clinical tests, and recently tests have changed to where they can be performed right next to clinicians. In this review, we introduce an updated overview of recent studies that are representative of the current trends in clinical microbiological techniques including PCR tests for infectious uveitis.

Primary vitrectomy or intravitreal antibiotics followed by early vitrectomy for acute endophthalmitis: A prospective observational study

BACKGROUND/AIMS

To compare outcomes of acute endophthalmitis (EO) managed with either primary vitrectomy (PV) or primary intravitreal antibiotics (vancomycin and ceftazidime) followed by early vitrectomy (PIAEV) combined with polymerase chain reaction (PCR)-based diagnostics.

METHODS

This was a prospective, comparative observational study of acute EO cases admitted to a regional vitreoretinal service over 18 months. Depending on whether immediate vitrectomy (within 6 h) was achievable, the EO cases were treated with either (1) PV or (2) PIAEV. Microbiology samples were collected either (A) before or (B) after administration of intravitreal antibiotics. The samples were analysed with broad-range 16S PCR and culture.

RESULTS

The study included 41 EO cases. There were 19 post-injection EO, 18 post-cataract EO, three post-vitrectomy EO, and one blebitis-related EO. Fifteen of 19 PV cases and 15 of 21 PIAEV had a clinically meaningful improvement in best-corrected visual acuity (BCVA) of at least 15 letters at 3 months (p = 0.58). One patient was lost to follow-up. Twenty-three cases were culture- and PCR-positive, and seven additional cases were culture-negative but PCR-positive (p = 0.02). PCR increased the diagnostic yield for samples collected both before and after administration of intravitreal antibiotics.

CONCLUSION

Primary vitrectomy or PIAEV allowed for vitrectomy for all cases of acute EO in a large region. Most eyes in both groups achieved a clinically meaningful improvement in BCVA. By combining culture with PCR in connection with the vitrectomy procedure, intravitreal antibiotics could be injected before microbiological sampling, thereby improving the door-to-treatment time without sacrificing microbial identification.

Application of metagenomic next-generation sequencing in suspected intraocular infections

PURPOSE

To evaluate the efficacy of metagenomic next-generation sequencing (mNGS) and to explore its value in the diagnosis of intraocular infection.

METHODS

A retrospective case-series study of patients with suspected intraocular infection was performed. Intraocular fluid samples were collected from all the patients and sent for mNGS. Detailed clinical data, the results of mNGS and other laboratory examinations, the sequencing data of mNGS, and the final diagnosis were recorded.

RESULTS

Fifteen eyes of 15 patients were included in the study. Eight samples were identified as positive for different kinds of pathogens by mNGS, which were all confirmed by other laboratory examinations or effective diagnostic treatment. The mNGS results were negative in seven samples. The final diagnosis was still intraocular infection in four of the seven negative results. Of these, one patient was diagnosed with fungal endophthalmitis according to the clinical characteristics and good treatment response to the anti-fungal therapy, one patient underwent vitrectomy and the bacterial culture of the vitreous sample was positive for Brucella melitensis, and two patients were diagnosed with ocular tuberculosis according to the positive T-SPOT test and effective anti-tuberculous treatments.

CONCLUSIONS

mNGS could be helpful in determining pathogens in cases of suspected intraocular infection. The mNGS protocols should be optimized for the detection of intracellular bacterial and fungal pathogens.

Update on Current Microbiological Techniques for Pathogen Identification in Infectious Endophthalmitis

Infectious endophthalmitis is a vision-threatening medical emergency that requires prompt clinical diagnosis and the initiation of treatment. However, achieving precision in endophthalmitis management remains challenging. In this review, we provide an updated overview of recent studies that are representative of the current trends in clinical microbiological techniques for infectious endophthalmitis.

Acute postoperative endophthalmitis: Microbiology from the laboratory to the bedside

Postoperative endophthalmitis is a dreaded complication of intraocular surgery. Acute presentations need prompt management and good knowledge of differential diagnoses. In the last 10 years, progress in direct microbial detection and identification from intraocular samples included the use of blood culture systems and, more recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, improving the rate of bacterial identification. Whatever the method used, diagnostic sensitivity is better for vitreous samples than for aqueous humor samples. Besides, molecular biology techniques have further improved the identification rate of infectious agents in intraocular samples. They also provide faster results compared to culture-based techniques. Quantitative real-time PCR (qPCR) can also determine the bacterial load in intraocular samples. Several studies have shown that intraocular bacterial loads in endophthalmitis patients are usually high, which helps differentiating infection from contamination. The prognostic value of qPCR remains to be validated. Whole genome DNA sequencing technologies facilitate direct and sequencing of single DNA molecules. They have the potential to increase the rate of microbiological identification. Some antibiotic resistance markers (e.g., methicillin resistance in staphylococci and vancomycin resistance in enterococci) may be detected earlier using molecular techniques (usually real-time PCR tests). Early determination of the involved microorganism and their antibiotic resistances can help establishing an earlier therapeutic strategy.

Validation of a multi-species-specific PCR panel to diagnose patients with suspected postoperative bacterial endophthalmitis

INTRODUCTION

Currently, patients suspected of endophthalmitis are referred to a tertiary centre for a vitreous biopsy and bacterial culture, thereby causing a treatment delay for the intravitreal antibiotics injection. We developed a new diagnostic tool, multi-mono-PCR (mm-PCR), not requiring viable bacteria, allowing antibiotic injection without delay. Performance of mm-PCR was tested on biopsies from patients with suspected postoperative endophthalmitis with known bacterial culture results.

METHODS

Most frequently occurring pathogens in endophthalmitis were determined using published data and treatment logs of endophthalmitis patient of the Rotterdam Eye Hospital. Vitreous biopsies from patients with suspected endophthalmitis were aliquoted in two parts. One part was sent out for bacterial culture and another was stored at -80°C for mm-PCR analysis and, as a backup, also by panbacterial PCR. Twelve vitreous samples from patients not suspected of having endophthalmitis were added as control samples.

RESULTS

Concordancy between bacterial culture and mm-PCR was 89% (24 of 27). All twelve control samples were negative. In three nonconcordant samples, the PCR results were most likely the correct ones.

CONCLUSION

mm-PCR results are highly concordant with bacterial culture. mm-PCR with panbacterial PCR as backup could be considered a diagnostic tool in patients with endophthalmitis, which would allow us to reverse the order of diagnosis and treatment while maintaining diagnostic surveillance, thereby preventing treatment delay.

Diagnosis and Surveillance of Neonatal Infections by Metagenomic Next-Generation Sequencing

Microbial infections cause significant morbidity and mortality in neonates. Metagenomic next-generation sequencing is a hypothesis-free and culture-free test that enables broad identification of pathogens and antimicrobial resistance genes directly from clinical samples within 24 h. In this study, we used mNGS for etiological diagnosis and monitoring the efficacy of antibiotic treatment in a cohort of neonatal patients with severe infections. The median age was 19.5 (3–52) days, median gestational age was 37.96 (31–40⁺³) weeks, and the median birth weight was 3,261 (1,300–4,300) g. The types of infectious diseases included pneumonia, sepsis, and meningitis. mNGS reported microbial findings in all cases, which led to changes in antibiotic treatment. These included cases of Mycobacterium tuberculosis, Legionella pneumophila, and Bacillus cereus. Eight of ten infants recovered after antibiotic adjustment and showed normal development during follow-up. On the other hand, neurological retardation was seen in two infants with meningitis. mNGS enabled etiological diagnosis and guided antibiotic therapy when all conventional methods failed to discover the culprit. It has the potential to cut down the overall cost and burden of disease management in neonatal infections.

Evaluation of the MRSA/SA ELITe MGB Assay for the Detection of Staphylococcus aureus in Bone and Joint Infections

Bone and joint infections represent a potentially devastating complication of prosthetic orthopedic joint replacement, thus requiring both rapid and appropriate antibiotic treatment. Staphylococcus aureus is one of the most common pathogens involved in this pathology. Being able to assert its presence is the first step of efficient patient management. This monocenter study evaluated the MRSA/SA ELITe MGB assay for the molecular detection of S. aureus and methicillin-resistant S. aureus (MRSA) in bone and joint biopsy specimens and synovial fluids. This test, together with conventional techniques, including standard cultures and the 16S rRNA amplification assay, was performed on 208 successive perioperative samples collected prospectively for 1 year obtained from 129 patients. Using conventional techniques, we detected a microbial pathogen in 76 samples from 58 patients, 40 of which were identified as S. aureus. The limit of detection (LOD) of the MRSA/SA ELITe MGB assay was experimentally determined for bone and joint biopsy specimens and synovial fluids using negative samples spiked with S. aureus ATCC 43300. The sensitivities of S. aureus detection with the MRSA/SA ELITe MGB assay were 82.5% (33/40 samples) and 97.5% (39/40 samples) using the manufacturer's LOD and an experimentally determined LOD, respectively. Interestingly, using the osteoarticular specific LOD, 15 additional samples were determined to be positive for S. aureus DNA with the MRSA/SA ELITe MGB assay; in all cases, these samples were obtained from patients considered to be infected with S. aureus according to their clinical and microbiological records. The results were available within 24 h, which could help to expedite therapeutic decisions.

The effect of postoperative oral antibiotic therapy on the incidence of postoperative endophthalmitis after phacoemulsification surgery in dogs: 368 eyes (1997-2010)

Purpose

To assess the effectiveness of postoperative administration of oral antibiotics at reducing the incidence of endophthalmitis following phacoemulsification cataract extraction in dogs.

Methods

Medical records of the University of Tennessee College of Veterinary Medicine were reviewed for cases having undergone phacoemulsification and divided according to whether or not they had received oral antibiotics postoperatively. Records were then evaluated for a diagnosis of endophthalmitis and incidence rates between the group receiving postoperative oral antibiotics and the group not receiving postoperative oral antibiotics were compared.

Results

A total of 215 patients (368 eyes) were identified by the search. One-hundred twelve patients (197 eyes) were treated with oral antibiotics postoperatively. One-hundred and three patients (171 eyes) were not treated with oral antibiotics postoperatively. Three cases of endophthalmitis were identified, with one in the antibiotic-treated group and two in the non-antibiotic treated group (P > 0.05, Fisher’s exact test).

Conclusions

The overall incidence of endophthalmitis at the University of Tennessee from 1997–2010 was 0.82%. The rate of post-phacoemulsification endophthalmitis was unaffected by the postoperative administration of oral antibiotics.

Microbiological diagnosis of endophthalmitis using nanopore targeted sequencing

BACKGROUND

Microorganism identification is critical for the early diagnosis and management of infectious endophthalmitis, but traditional culture can yield false-negative results. Nanopore targeted sequencing (NTS) is a third-generation sequencing technique with multiple advantages. This study aimed to test aqueous humour or vitreous fluid samples from presumed cases of infectious endophthalmitis using NTS to evaluate the feasibility of NTS in diagnosing endophthalmitis, especially for culture-negative cases.

METHODS

This prospective study enrolled patients who presented to the Department of Ophthalmology of Union Hospital (Wuhan, China) between June 2018 and December 2020. The samples were sent immediately for routine microbiology culture processing and NTS assay.

RESULTS

NTS identified microorganisms in 17 of 18 cases (94.4%) (eight culture-positive cases, nine culture-negative cases, and one case unavailable for culture). There was a high-quality match between culture and NTS for culture-positive cases. In the eight culture-negative cases and the case unavailable for culture, NTS detected either bacteria, fungi, or a mixture of bacteria and fungi in the intraocular fluids. The average waiting times for the results of bacterial and fungal cultures were 48 and 72 h, respectively. The average time for the NTS results was 12 h.

CONCLUSIONS

NTS appears to be a promising diagnostic platform for diagnosing infectious endophthalmitis, even for culture-negative cases.

Clinical Characteristics and Outcomes in 314 Japanese Patients with Bacterial Endophthalmitis: A Multicenter Cohort Study from J-CREST

Bacterial endophthalmitis is an intraocular infection that causes rapid vison loss. Pathogens can infect the intraocular space directly (exogenous endophthalmitis (ExE)) or indirectly (endogenous endophthalmitis (EnE)). To identify predictive factors for the visual prognosis of Japanese patients with bacterial endophthalmitis, we retrospectively examined the bacterial endophthalmitis characteristics of 314 Japanese patients and performed statistics using these clinical data. Older patients, with significantly more severe clinical symptoms, were prevalent in the ExE group compared with the EnE group. However, the final best-corrected visual acuity (BCVA) was not significantly different between the ExE and EnE groups. Bacteria isolated from patients were not associated with age, sex, or presence of eye symptoms. Genus Streptococcus, Streptococcus pneumoniae, and Enterococcus were more prevalent in ExE patients than EnE patients and contributed to poor final BCVA. The presence of eye pain, bacterial identification, and poor BCVA at baseline were risk factors for final visual impairment.

Endophthalmitis after cataract surgery: an update on recent advances

PURPOSE OF REVIEW

Prevention and management of postcataract endophthalmitis remain quite relevant for anterior segment and vitreoretinal surgeons. Although the Endophthalmitis Vitrectomy Study, published in 1996, remains the only level 1 evidence for the management of postcataract endophthalmitis, recent advances have resulted in an evolution of practice patterns. The aim of this review is to summarize the literature regarding postcataract endophthalmitis with a focus on the last 18 months.

RECENT FINDINGS

The IRIS registry indicates the rates of endophthalmitis are decreasing in the United States, and the outcomes appear to be improving. Intracameral moxifloxacin has become more widely accepted and intracameral vancomycin has been shown to be associated with retinal vasculitis. The role of systemic antibiotics and vitrectomy is unclear and practice patterns vary widely.

SUMMARY

Although practice patterns vary, prevention and treatment of endophthalmitis after cataract surgery continues to improve. More uniform guidelines regarding surgical and medical therapy are necessary but the standard of prompt referral to a vitreoretinal specialist for immediate intravitreal antibiotics remains the most important intervention in the management of postcataract endophthalmitis.

Application of Metagenomic Sequencing in the Diagnosis of Infectious Uveitis

Purpose: to summarize the origin and very recent history of the use of metagenomic sequencing for the diagnosis of infectious uveitis, convey the technique as described by one of the primary institutions experimenting with the technology, and present recent successful applications of the technology as well as potential advantages and pitfalls compared to other current diagnostic tools.Methods: review of peer-reviewed literature concerning metagenomic sequencing for the diagnosis of infectious uveitis.Conclusion: compared to existing diagnostic methods, metagenomic deep sequencing is a sensitive, unbiased, and comprehensive technique with great potential for diagnosing the causative pathogens of cases of infectious uveitis. However, many issues remain to be addressed in the process of developing this technology, including but not limited to the potentially overwhelming amount of information generated, definition of diagnostic thresholds, demonstration of validity, contamination, and cost.

Post-intravitreal injection endophthalmitis secondary to Turicella otitidis: a case report

Background

Endophthalmitis is a rare but potentially devastating complication of intravitreal injection. The causative organism plays an important role in prognosis following endophthalmitis. Here we present the first reported case of Turicella otitidis endophthalmitis, which is notable for a delayed presentation.

Case presentation

A 71 year old male who was receiving intravitreal aflibercept injections for neovascular age-related macular degeneration presented 4 weeks after his most recent intravitreal injection and was found to have endophthalmitis. Polymerase chain reaction (PCR) testing of aqueous fluid was positive for Turicella otitidis. The endophthalmitis responded well to treatment with intravitreal antibiotics.

Conclusions

Coryneform bacteria are a rare cause of endophthalmitis, and this is the first reported case of endophthalmitis caused by the corynebacterium species Turicella otitidis. As in this case, post-intravitreal injection endophthalmitis may have a bacterial etiology even with delayed presentation. The relatively indolent disease course and excellent response to intravitreal antibiotics is consistent with previous ophthalmic reports regarding other corynebacteria, as well as with otolaryngology and hematology oncology reports addressing Turicella otitidis specifically. This case supports the growing body of evidence for pathogenicity of Turicella otitidis and demonstrates the utility of PCR for diagnosis in small volume aqueous specimens.