Persistently Vitreous Culture-Positive Exogenous Bacterial Endophthalmitis

[Distribution and Antibiotic Resistance Analysis of Ocular Bacterial Pathogens at a Tertiary Hospital From 2012 to 2021]

Objective

To analyze the distribution of ocular bacterial pathogens and their antibiotic resistance status at a tertiary-care hospital and to provide a reference for the appropriate use of antibiotics.

Methods

Retrospective analysis was conducted with bacteria isolated from the ophthalmic samples sent for lab analysis at a tertiary-care hospital from 2012 to 2021. The suspected bacterial strains were identified with automated systems for microbial identification and susceptibility analysis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometer. VITEK 2 Compact, an automated microbial identification and antibiotic susceptibility analysis system, was used for antimicrobial susceptibility testing.

Results

A total of 1556 ophthalmology bacteria culture samples were collected, 574 of which showed bacterial growth, presenting an overall positive rate of 36.89%. Of the isolated bacteria, Gram-positive cocci, Gram-positive bacilli, Gram-negative bacilli, and Gram-negative cocci accounted for 63.15% (377/597), 18.76% (112/597), 17.09% (102/597), and 1.00% (6/597), respectively. Among the bacteria isolated in different years over the course of a decade, Gram-positive cocci always turned out to be the main cause of eye infections. Of the Gram-positive cocci, 73.47% (277/377) were isolated from patients with endophthalmitis, with the most important species being Staphylococcus epidermidis, which was followed by Streptococcus viridans. The rest, or 26.53% (100/377), of the Gram-positive cocci were isolated from patients with external eye infections, with the main isolated strains being Staphylococcus epidermidis, Streptococcus viridans, and Staphylococcus aureus. More than 70% of Staphylococcus epidermidis isolated from both endophthalmitis and external eye infections were resistant to methicillin. No strains resistant to vancomycin, linezolid, or tigecycline were detected. Staphylococcus epidermidis isolated from patients with external eye infections had a low rate of resistance to levofloxacin (2/27 or 7.41%), whereas those isolated from patients with endophthalmitis had a higher resistance rate (43/127 or 33.86%). The difference in drug resistance rate between the two groups was statistically significant (P<0.05).

Conclusion

The chief ocular bacterial pathogens identified in a tertiary-care hospital were Gram-positive cocci, among which, Staphylococcus epidermidis was the most common species. The Staphylococcus epidermidis identified in the hospital had a high rate of resistance to oxacillin, but remained highly sensitive to vancomycin, linezolid, and tigecycline. The endophthalmitis caused by Staphylococcus epidermidis in the hospital can be treated empirically with vancomycin and then the treatment plan can be further adjusted according to the results of the drug susceptibility test. However, the establishment of the breakpoint of drug susceptibility test is mainly based on the model of bloodstream infection and has limited reference value for the treatment of eye infection. The required drug distribution concentration at the infection site can be achieved by dose increase or local administration.

The Effectiveness and Safety of Intravitreal Injections of Voriconazole in the Treatment of Fungal Endophthalmitis: A Systematic Review

Background: Fungus endophthalmitis is a rare and serious infection that is treated with systemic and topical antifungal drugs. There is no clear consensus on the treatment of fungal endophthalmitis with intravitreal injections (IVIs) of voriconazole. This systematic review aims to summarize the literature on IVIs of voriconazole for fungal endophthalmitis. Methods: We conducted a systematic review of the literature to determine the effectiveness and safety of IVIs of voriconazole in the treatment of fungal endophthalmitis. We searched databases such as PubMed and Embase using the following search terms "Endophthalmitis" AND "Intravitreal Injections" AND "Voriconazole" with date limits of January 1, 1900, to December 31, 2022. We included all reports on humans, which described clinical outcomes of IVIs of voriconazole in the treatment of fungal endophthalmitis, including randomized controlled trials (RCTs) and case series. A descriptive synthesis of the data was conducted with a pooling of data for interventions. Results: One RCT and 21 retrospective studies were analyzed in this review. In these reports, a wide range of heterogeneous treatment regimens was used, including IVI in combination with other drugs, systemic therapy in combination with other agents, and surgery. Combined with other treatments, intravitreal voriconazole results in a favorable anatomical and clinical cure that was well tolerated. Conclusions: Reports on IVIs of voriconazole for fungal endophthalmitis demonstrate a heterogeneous approach to treatment. Of these, IVIs of voriconazole in anatomical and clinical outcomes appeared to be highly effective, although more data on its safety are needed.

Clinical Practice Update: Management of Infectious Endophthalmitis After Intravitreal Anti-VEGF Injection

Although infectious endophthalmitis after intravitreal antivascular endothelial growth factor injections is rare, it is the most feared and potentially devastating complication of this procedure. There is no high-level evidence to provide definitive guidance on the management of endophthalmitis occurring after intravitreal injection (IVI). This clinical practice update reviews the published literature regarding post-IVI endophthalmitis and highlights areas in which further research is needed to better guide its management.

Endophthalmitis at a tertiary referral center: Characteristics and treatment outcomes over three decades

Purpose: To explore the incidence, pathogens, treatment, and prognosis of endophthalmitis.

Methods: Patients who were diagnosed with endophthalmitis from January 1990 to October 2020 at Peking Union Medical College Hospital were retrospectively reviewed and examined. Subgroup analysis was conducted regarding different initial treatment methods for eyes without concurrent retinal detachment (RD) at presentation.

Results: A total of 249 eyes of 233 patients were included in this retrospective study. The most common clinical scenario was exogenous endophthalmitis (60.6%). The most frequent bacteria and fungi were coagulase-negative staphylococci (10.0%) and candida (6.8%), respectively. Retinal with/without choroid detachment was the most common complication after treatment. Patients with endogenous endophthalmitis were more likely to have binocular involvement; there were also more patients with diabetes mellitus or immunosuppressive diseases, and the prognosis of visual acuity (VA) was poorer. There were more eyes with concurrent RD at presentation that underwent serious complications after treatment (p < 0.05), and the visual outcome was worse than that without concurrent RD (p < 0.05). Subgroup analysis was conducted according to different initial treatments in eyes without concurrent RD. Group 1 received pars plana vitrectomy (PPV) with intravitreal injection of antibiotics (IVI) as initial treatment, Group 2 was initially treated with IVI only, and Group 3 was initially treated with nonsurgical treatment. More eyes that initially received IVI alone and nonsurgical treatment required additional treatments, especially additional PPV. VA in both Groups 1 and 2 significantly improved by the final VA. However, there was no significant difference in final VA between the two groups. There was an insignificant trend that serious posttreatment complications were more common in Group 1. In Group 1, 17 eyes received silicone oil or gas tamponade at the same time, whereas 62 did not. Eyes that were initially treated with PPV + IVI while without tamponade needed more additional treatments and additional IVI.

Conclusion: Endophthalmitis is a devastating intraocular disease and requires early intervention. Endogenous endophthalmitis has a poorer visual prognosis than exogenous entity. PPV + IVI as an initial treatment may reduce additional therapy.

Application Progress of High-Throughput Sequencing in Ocular Diseases

Ocular diseases affect multiple eye parts and can be caused by pathogenic infections, complications of systemic diseases, genetics, environment, and old age. Understanding the etiology and pathogenesis of eye diseases and improving their diagnosis and treatment are critical for preventing any adverse consequences of these diseases. Recently, the advancement of high-throughput sequencing (HTS) technology has paved wide prospects for identifying the pathogenesis, signaling pathways, and biomarkers involved in eye diseases. Due to the advantages of HTS in nucleic acid sequence recognition, HTS has not only identified several normal ocular surface microorganisms but has also discovered many pathogenic bacteria, fungi, parasites, and viruses associated with eye diseases, including rare pathogens that were previously difficult to identify. At present, HTS can directly sequence RNA, which will promote research on the occurrence, development, and underlying mechanism of eye diseases. Although HTS has certain limitations, including low effectiveness, contamination, and high cost, it is still superior to traditional diagnostic methods for its efficient and comprehensive diagnosis of ocular diseases. This review summarizes the progress of the application of HTS in ocular diseases, intending to explore the pathogenesis of eye diseases and improve their diagnosis.

Early and complete vitrectomy versus tap and inject in acute post cataract surgery endophthalmitis presenting with hand motion vision; a quasi-experimental study

BACKGROUND

Based on endophthalmitis vitrectomy study, intravitreal injection of antibiotics is preferred for initial management of cases of acute post cataract surgery endophthalmitis (APCE) with presenting vision of hand motions (HM). This study aimed to compare outcomes of early and complete vitrectomy (VIT) and vitreous tap and antibiotic injection (T&I) in cases of APCE presented with vision of HM.

METHODS

In this prospective study, cases of APCE with vision of HM between 2018 and 2020 were enrolled. According to the time of presentation, the patients were arranged into two groups (VIT vs. T&I). Demographic data, elapsed time to developing endophthalmitis, past medical history, microbiology results, complications, and final visual acuity were recorded and analyzed.

RESULTS

Seventy-six eyes of 76 patients were enrolled. Fifty-three eyes underwent T&I and twenty-three were arranged into the VIT group. Past medical history of 34.2% of patients was significant for diabetes mellitus. There was a statistically significant lower logMAR in VIT group compared to T&I group (diff = 0.14, 95% CI: 0.04 to 0.24, P-value = 0.007). The comparison of the diabetic and non-diabetic patients in both groups showed that the visual outcome was better in non-diabetic cases compared to the diabetic subjects. There was no statistically significant difference between the diabetic and non-diabetic groups regarding the superiority of procedure.

CONCLUSION

Based on our results, we could recommend that it's maybe better to do early and complete vitrectomy as the initial management of APCE with the vision of HM. Past medical history of diabetes mellitus is not a determining factor for choosing initial management between vitrectomy and antibiotic injection.

Atypical Microbiological Feature of Infectious Endophthalmitis on Jeju Island: A 10-Year Study at a Single Tertiary Referral Center

Background

To analyze the microbiological causes of infectious endophthalmitis on an isolated island over ten years.

Methods

A retrospective review of the medical records of 49 eyes clinically diagnosed with infectious endophthalmitis between January 2009 and December 2018 was done. The subjects were recruited from a single tertiary referral center on Jeju Island. The baseline characteristics of all subjects were investigated, and a culture examination was performed. The isolated pathogens were analyzed to determine how their microbiological features differed from those in regions with different geographical conditions.

Results

Of the 49 eyes, causative microorganisms were identified in 27 eyes (55.1%). Bacteria were found in 24 cases and fungi in 3 cases. Among the exogenous causes, Staphylococcus species (Staphylococcus aureus, S. epidermidis, and S. hominis) were the most common pathogens (7 cases). Achromobacter xylosoxidans was the second most common causative pathogen (4 cases) followed by Moraxella species (3 cases). The most frequent endogenous origin was due to Klebsiella pneumoniae (6 cases). The subjects were divided into two groups according to the treatment results and analyzed for predisposing factors related to visual outcomes. The presence of diabetes mellitus (P = 0.038) and initial visual acuity (P ≤ 0.001) were significant predisposing factors for visual outcomes.

Conclusion

The causative microorganisms of endogenous endophthalmitis on Jeju Island were not different from those reported previously. However, isolated exogenous microorganisms were different from those reported in other studies from inland areas. A high incidence and atypical clinical features of Achromobacter xylosoxidans and Moraxella in exogenous endophthalmitis were observed, reflective of the distinct climatic features of Jeju Island: high humidity and temperature. Therefore, considering the causative microorganisms of exogenous endophthalmitis, it may be assumed that the causative microorganisms of exogenous endophthalmitis and its clinical manifestations differ according to the region.

Comparative Outcomes of Primary Vitrectomy Versus Tap and Inject for Endophthalmitis Following Phacoemulsification Cataract Surgery

PURPOSE

To compare functional and anatomical outcomes, rates of culture positivity and number of procedures in eyes with endophthalmitis following phacoemulsification surgery, treated with either primary vitrectomy and intravitreal antibiotics or vitreous tap and antibiotic injection (T&I).

METHODS

Patients developing endophthalmitis after phacoemulsification surgery between 2007 and 2016 were identified, and outcomes were compared between the two treatment groups.

RESULTS

19 patients underwent a primary vitrectomy and 22 underwent a T&I. There was a significant improvement in visual acuity after T&I (p=.003) and primary vitrectomy (p=.00005). The median improvement in visual acuity was significantly greater for the primary vitrectomy group than the T&I group (p=.024). 64% of eyes were culture positive with the initial T&I, and 63% with primary vitrectomy (p=1.00). Two eyes initially culture negative with a T&I, and three eyes that were culture positive with a T&I were subsequently culture positive with a vitrectomy 24-72 hours later. 68% of patients who underwent a T&I required an additional procedure, compared to 26% of the vitrectomy group (p=.01). The T&I group underwent a mean of 2.3 procedures each, and the primary vitrectomy group underwent 1.5 (p=.03).

CONCLUSIONS

Eyes with endophthalmitis treated with a primary vitrectomy demonstrated greater visual improvement and needed fewer procedures than those initially treated with a T&I. Viable bacteria were only seen in subsequent procedures in the T&I group, indicating that primary vitrectomy was superior at sterilizing the eye.

Clinical Course and Characteristics of Eyes with Recurrent Episodes of Endophthalmitis

PURPOSE

Infectious endophthalmitis is a devastating, yet rare, complication after intraocular surgery, trauma, and systemic illness. Given its rare incidence, few patients would be expected to experience more than 1 episode of infectious endophthalmitis in their lifetime. We reviewed our patients who were diagnosed with and treated for at least 2 separate episodes of endophthalmitis.

DESIGN

A retrospective, consecutive case series was conducted of patients managed at Associated Retinal Consultants PC (Royal Oak, Michigan) from January 2013 through December 2019.

PARTICIPANTS

Patients were identified with the diagnosis of endophthalmitis by International Classification of Diseases, Ninth and Tenth Editions, codes.

METHODS

Those diagnosed and then treated either with a vitreous tap and intravitreal injection of antibiotics or with pars plana vitrectomy at least twice were included. Those treated multiple times for the same episode of endophthalmitis were excluded.

MAIN OUTCOME MEASURES

Cause and risk factors for recurrent endophthalmitis.

RESULTS

Charts of 535 patients were reviewed, and 12 patients met inclusion criteria. The median age at initial presentation was 72.5 years, and 33.3% were men. Eight of the 12 patients (66%) experienced recurrent endophthalmitis in the same eye, and 4 of the 12 patients (33%) experienced separate episodes in different eyes. The average time between episodes was 604 days (range, 90-2366 days). The average follow-up from the second episode was 492 days (range, 119-1185 days). The most common cause for both the first and second episodes was recent intravitreal injection (50% and 58.3%, respectively) followed by surgery associated (41.6% and 33.3%, respectively). The cause was the same for the first and second episodes of 8 patients (75%). Of the 24 recorded episodes of endophthalmitis, culture results were positive in 41.6%, with coagulase-negative Staphylococcus being the most common bacteria identified.

CONCLUSIONS

Recurrent endophthalmitis is rare and seen most commonly after intravitreal injections. Most patients in this series showed culture-negative results. Each successive episode of endophthalmitis was associated with a worse final visual outcome. The cumulative number of intravitreal injections may be an independent risk factor for recurrent postinjection endophthalmitis.

Clinical Features, Antibiotic Susceptibilities, and Treatment Outcomes of Endophthalmitis Caused by Staphylococcus epidermidis

PURPOSE

To report the clinical features, antibiotic susceptibilities, and visual acuity outcomes with endophthalmitis caused by methicillin-sensitive Staphylococcus epidermidis and methicillin-resistant S. epidermidis.

DESIGN

Retrospective case series.

PARTICIPANTS

All patients seeking treatment at a tertiary referral center between 2006 and 2016 with endophthalmitis caused by S. epidermidis.

METHODS

All records were reviewed for patients with a clinical diagnosis of endophthalmitis and positive vitreous culture results for S. epidermidis. Data were compared with the prior series at the same institution.

MAIN OUTCOME MEASURES

Clinical settings, antibiotic susceptibilities, and visual acuity.

RESULTS

Among 96 eyes of 96 patients, the most common postprocedural clinical settings were cataract surgery (47/96 [49%]), intravitreal injection (21/96 [22%]), trauma (8/96 [8%]), glaucoma surgery (7/96 [7%]), and penetrating keratoplasty (5/96 [5%]). The initial treatment included intravitreal vancomycin and ceftazidime in 89 of 96 eyes (93%) and intravitreal vancomycin and amikacin in 7 of 96 eyes (7%). A vitreous tap and injection with antibiotics was performed as the initial treatment in 83 of 96 eyes (86%) and pars plana vitrectomy was performed in 13 of 96 eyes (14%). All isolates were sensitive to vancomycin in both decades. In the most recent series, visual acuity at last follow-up was 5/200 or better in 68 of 96 eyes (71%) compared with 71 of 86 eyes (83%) in the prior study. In the current study, susceptibility to methicillin and moxifloxacin was present in 45 of 96 eyes (47%) and 29 of 85 eyes (34%), respectively, compared with 34 of 86 eyes (40%) and 27 of 39 eyes (69%) in the prior study. Final visual acuity was not significantly different between those eyes that were methicillin or fluoroquinolone sensitive and those that were resistant.

CONCLUSIONS

In the current and prior series, all S. epidermidis isolates were sensitive to vancomycin. Visual acuity outcomes were not dependent on methicillin or fluoroquinolone sensitivity.