Endophthalmitis and Concurrent or Delayed-Onset Rhegmatogenous Retinal Detachment Managed With Pars Plana Vitrectomy, Intravitreal Antibiotics, and Silicone Oil

Characteristics and Risk Factors for Rhegmatogenous Retinal Detachment Related to Endophthalmitis

Purpose: To evaluate the risk factors for the development of concurrent or delayed-onset rhegmatogenous retinal detachment (RRD) related to endophthalmitis as well as the anatomic and visual outcomes with subsequent RRD repair. Methods: In this retrospective case study, a 2-tailed t test (continuous) and Fisher exact test were used to determine statistical significance of the observed findings. The relative risk (RR) and 95% CIs were calculated to assess statistical significance. Results: Of the 170 patients included, 22 were found to have a concurrent or subsequent RRD. Initial treatment with pars plana vitrectomy (PPV) (RR, 3.544; 95% CI, 1.650-7.614), aphakia (RR, 4.150; 95% CI, 1.434-12.011), endogenous endophthalmitis (RR, 2.684; 95% CI, 1.065-6.764), and posterior synechiae (RR, 3.026; 95% CI, 1.408-6.505) were statistically significant risk factors for RRD. Anatomically successful repair was achieved in 77.7% of patients. Conclusions: In addition to preexisting risk factors, the initial treatment of endophthalmitis may be a significant risk factor for RRD development, with a higher incidence of subsequent RRD in patients who have PPV as the initial treatment for endophthalmitis.

Postintravitreal Injection Endophthalmitis: Incidence, Characteristics, Management, and Outcome

Purpose

Postintravitreal injection (IVI) endophthalmitis is a rare but devastating complication. Herein, we report the incidence ,and clinical and microbiological characteristics, as well as the visual outcome, in IVIs endophthalmitis in two medical centers.

Methods

All patients undergoing intravitreal injections between 1/2018 and 12/2019 in two large medical centers were analyzed for post-IVI endophthalmitis.

Results

Of the total of 51,356 IVIs performed, 23 cases of post-IVI endophthalmitis were diagnosed, yielding an overall incidence of 0.045%. The median interval from IVI to symptoms onset was 2 days (IQR: 1-5). Cultures were positive in 56% of the cases (100% Gram-positive bacteria and 76% coagulase-negative staphylococcus). Parameters associated with higher culture-positive rates included samples taken during vitrectomy, WBC on vitreous smear, the number of IVIs in the 12 months prior to presentation, and the time interval from last IVI to diagnostic sampling. At 6- and 12-month follow-up, the median change in VA (logMAR) was -1.10 (IQR: (-1.32)-(-0.40)) and -1.02 (IQR: (-1.10)-(-0.30)), respectively. Younger age and better BCVA at presentation were associated with better VA outcome, while positive culture result and systemic steroids treatment were each associated with the worse visual outcome. We found no difference in visual outcomes between PPV and TAI as a primary procedure.

Conclusion

Post-IVI endophthalmitis is a rare complication, and most patients do not regain their initial VA. Certain parameters (clinical, microbiological, and therapeutic) may help anticipate the outcome and guide decision making regarding diagnosis and treatment.

Retinal detachment after post-operative endophthalmitis: clinical characteristics, outcomes and risk factors

PURPOSE

To describe clinical characteristics, risk factors, and outcomes of rhegmatogenous retinal detachment (RRD) following treatment of postoperative endophthalmitis (PE).

METHODS

Analysis of cross-referenced data from two service reviews of patients with RRD and bacterial PE treated between 01/01/2013 and 01/07/2020. The main outcome measure was final best-corrected visual acuity (BCVA). Secondary measures include proportion of patients with BCVA of ≤ 0.3 logMAR and ≥ 1.0 logMAR, rate of phthsis, and rate of eye removal.

RESULTS

Ninety-four cases of PE were analysed finding 21 cases of RRD (22%). Seven (35%) experienced recurrent RRD. Seven eyes (35%) were left with permanent silicone oil fill. All RRD cases had vitrectomy. After PE with RRD the median BCVA was 1.1 logMAR, compared with 0.4 logMAR for PE without RRD (p < 0.04). Fifty-seven percent (12/21) of RRD eyes attained BCVA of ≥ 1.0 logMAR vs. 29% (21/73) of PE without RRD (p = 0.01). Nineteen percent (4/21) of eyes with RRD attained BCVA of ≤ 0.3 logMAR, whereas those without RRD did so in 43% (31/73) of cases (p = 0.02). Five eyes with RRD (24%) and 2 eyes without RRD (3%) developed phthisis (p < 0.01). Three non-RRD cases required removal of the eye (4%, p = 0.46). Higher bacterial virulence was associated with worse final BCVA (2.1 logMAR vs. 0.3 logMAR; p < 0.01). RRD rate did not differ by bacterial virulence (OR 1.9; CI95: 0.6-6.9; p = 0.24).

CONCLUSIONS

RRD following PE leads to worse clinical outcomes. Eyes which developed RRD were more likely to have undergone vitrectomy. Final BCVA was worse in cases with more virulent micro-organisms.

MEDIUM-TERM PERFLUORO-N-OCTANE AS RESCUE POSTOPERATIVE TAMPONADE FOR VERY COMPLEX RETINAL DETACHMENTS: ANATOMICAL AND FUNCTIONAL OUTCOMES

PURPOSE

To report the anatomical and functional outcomes of medium-term perfluoro-n-octane (PFO) tamponade as a rescue procedure in very complex retinal detachments (RDs).

METHODS

We reviewed the case records of 35 consecutive patients who underwent vitrectomy for very complex RDs due to diverse etiologies. The surgical complexity was so graded because of the intraoperative failure to ascertain complete retinal reattachment; perfluoro-n-octane was used as rescue tamponade for 2 to 4 weeks. The second intervention included additional membrane peeling, retinectomy, endophotocoagulation, and gas/silicone oil tamponade. The minimum follow-up was 3 months after the final intervention: the primary outcome was retinal reattachment and the secondary outcome was change in best-corrected visual acuity (BCVA).

RESULTS

The most common presentations were severe trauma with retinal incarceration, preretinal and subretinal hemorrhage, or chronic/recurrent RDs with anterior proliferative vitreoretinopathy. Preoperative BCVA was ≤counting fingers in 31 (88.6%) patients. Complete retinal attachment without any tamponade was achieved in 33 (94.3%) eyes. best-corrected visual acuity improved in 30 (85.7%) eyes: 16 (45.7%) had BCVA ≥20/200 and 21 (60%) regained ambulatory vision (≥5/200). Two eyes developed keratopathy, and four needed antiglaucoma medications.

CONCLUSION

We achieved excellent anatomical outcomes and acceptable functional outcomes in nearly inoperable RDs with few side effects. Medium-term perfluoro-n-octane tamponade can be used as a salvage procedure in very complex RDs where intraoperative reattachment cannot be ensured.

Endophthalmitis in Silicone Oil-Filled Eyes

Incidences of post pars plana vitrectomy (PPV) endophthalmitis vary between 0.02% and 0.13%, and infectious endophthalmitis in silicone oil-filled eyes is even rarer. We performed a literature review to describe the incidence, protective and predisposing factors, causative pathogens, management options, and prognosis of infectious endophthalmitis in silicone oil-filled eyes. Various studies have elucidated different aspects of this condition. Causative pathogens commonly include commensals. Traditional management involves the removal of silicone oil (SO), intravitreal antibiotics and then SO re-injection. Alternatively, injecting intravitreal antibiotics into silicone oil-filled eyes has also been reported. Visual prognoses are uniformly guarded. Due to the uncommon nature of this condition, studies are limited either by their retrospective design or by small sample sizes. However, observational studies, case series, and case reports can play an important role in rare conditions until larger studies are conducted. This comprehensive review aims to summarise the information available in the literature, to act as a good source for ophthalmologists looking for answers on this topic, and to suggest areas for future development.

Epiretinal Amniotic Membrane in Complicated Retinal Detachment: a Clinical and In Vitro Safety Assessment

INTRODUCTION

Amniotic membrane (AM) is a popular treatment for external ocular diseases. First intraocular implantations in other diseases reported promising results. Here, we review three cases of intravitreal epiretinal human AM (iehAM) transplantation as an adjunct treatment for complicated retinal detachment and analyze clinical safety. Possible cellular rejection reactions against the explanted iehAM were evaluated and its influence was assessed on three retinal cell lines in vitro.

METHODS

Three patients with complicated retinal detachment and implanted iehAM during pars plana vitrectomy are retrospectively presented. After removal of the iehAM at subsequent surgery, tissue-specific cellular responses were studied by light microscopy and immunohistochemical staining. We investigated the influence of AM in vitro on retinal pigment epithelial cells (ARPE-19), Müller cells (Mio-M1), and differentiated retinal neuroblasts (661W) . An anti-histone DNA ELISA for cell apoptosis, a BrdU ELISA for cell proliferation, a WST-1 assay for cell viability, and a live/dead assay for cell death were performed.

RESULTS

Despite the severity of the retinal detachment, stable clinical outcomes were obtained in all three cases. Immunostaining of the explanted iehAM showed no evidence of cellular immunological rejection. In vitro, there was no statistical significant change in cell death or cell viability nor were proliferative effects detected on ARPE-19, Müller cells, and retinal neuroblasts exposed to AM.

CONCLUSION

iehAM was a viable adjuvant with many potential benefits for treatment of complicated retinal detachment. Our investigations could not detect any signs of rejection reactions or toxicity. Further studies are needed to evaluate this potential in more detail.

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.

Anatomical and Functional Outcomes in Delayed Onset versus Concurrent Retinal Detachment in Endophthalmitis

Purpose

To determine the functional and anatomical outcomes of patients with endophthalmitis with concurrent or delayed onset retinal detachment (RD), and compare the preoperative, intraoperative and postoperative features.

Patients and Methods

This was a retrospective review of 121 eyes in 121 patients presenting with endophthalmitis and RD. Subjects were categorized into two groups: endophthalmitis with delayed onset RD (group 1, N=76) and endophthalmitis with concurrent RD (group 2, N=45).

Results

The mean age of patients in groups 1 and 2 was 38.21±21.60 and 46.78±24.42 years, respectively (P=0.047). Exogenous endophthalmitis was common in both groups 1 and 2 (86.84% and 84.44%, respectively). No significant differences were found between the groups in the type of RD, retinal breaks, number of quadrants involved or proliferative vitreoretinopathy grade. In the overall cohort, visual acuity improved post-surgery in one-third of the patients who were in the near or total blindness category at presentation. We found good anatomical success rates of an attached retina in both groups 1 and 2 (84.3% and 77.7%, P=0.376).

Conclusion

Our study presents the results of patients with endophthalmitis and delayed onset RD or concurrent RD. It shows a few differences in presentation between the groups, but the anatomical and functional outcomes were almost the same.

Primary small gauge pars plana vitrectomy and silicone oil endotamponade for endophthalmitis after cataract surgery: Clinical and OCT findings

BACKGROUND

Retrospective analysis of morphological and functional outcomes after pars-plana vitrectomy and Silicone-Oil (SO) endotamponade in acute postoperative endophthalmitis (APOE).

METHODS

Minimum follow-up was 6 months. Every included patient received best-corrected visual acuity (BCVA) assessment, pre-operatively and at last follow-up. Spectralis OCT was used to investigate disorganization of inner (DRIL) and outer (DROL) retinal layers at 1, 3, 6 months and at last follow-up. OCT-A was performed to assess foveal avascular zone (FAZ) and vascular perfusion density (VPD) at 6 months and at last follow-up.

RESULTS

Seventeen eyes were recruited. Postoperative findings: BCVA ≥ 20/40 (in 14 eyes); epiretinal membranes (13); hyperreflective epiretinal material soon after surgery in (6) SO-filled eyes; inner retinal layers atrophy (5); macular edema (2); DROL (4) with persistent EZ disruption at final visit (2); no significant difference between study and fellow eyes in central macular thickness, FAZ and VPD; VPD decreased in all cases with prominent disorganization of retinal architecture.

CONCLUSION

OCT changes after APOE can be persistent or completely/partially self-resolving and seems related to the outward progression path of the infection/inflammation from the vitreous cavity to the inner and outer retina, rather than to the surgery.

The Role of Silicone Oil in the Surgical Management of Endophthalmitis: A Systematic Review

(1) Background: We aimed to systematically review the current literature to evaluate if in patients with postoperative endophthalmitis treated with pars plana vitrectomy, silicone oil tamponade could provide a useful contribution to the control and eradication of infection and if it could influence anatomical recovery and functional outcome. (2) Randomized controlled trials, cross-sectional studies, case series, and case reports published in the English language in peer-reviewed journals were included. No restriction was placed based on the study location. We used medical subject headings (MeSH) and text words. We searched MEDLINE (OVID and PubMed), Google Scholar, ISI Web of Science (Thom-on-Reuters), and the Cochrane Library (Wiley) from January 1995 to the present. To ensure literature saturation, we scanned the reference lists of included studies or relevant reviews identified through the search. Risk of Bias was assessed using the Newcastle-Ottawa scale for longitudinal studies and Cochrane risk-of-bias tool for randomized trials. (3) Results: abstracts of 75 articles were selected for full-text reading; after full-text reading, 44 articles were taken into consideration in the systematic review. 5 out of 7 in vitro experimental studies demonstrated antimicrobial activity against different species of bacteria and fungi. The use of SO as endotamponade associated with PPV led to better visual acuity and a lower rate of retinal detachment and the need for additional surgery. (4) Conclusions: Silicone oil reduces the risk of postoperative retinal detachment, especially in case of undetected retinal breaks, produces compartmentalization of the eye, may lead to early visual recovery, allows laser photocoagulation, prevents severe postoperative hypotony and has antimicrobic activity due to an inhibitory effect for several species of pathogens. Concerns regarding possible toxic effects on the retina and optic disc, compartmentalization and impaired washout of pathogen toxins have been reported. It may also influence intravitreal antibiotic distribution and clearance.

Endophthalmitis After Intravitreal Anti-Vascular Endothelial Factor Injections: Outcomes of Eyes Managed Without Microbiologic Cultures

PURPOSE

To evaluate outcomes of eyes that developed endophthalmitis after intravitreal anti-vascular endothelial growth factor injections that were managed without microbiologic cultures.

DESIGN

Retrospective, single-center, comparative cohort study.

METHODS

We included all eyes with postinjection endophthalmitis from July 1, 2013, to September 1, 2019. Endophthalmitis cases were divided into the culture group if treated with intravitreal antibiotics and a vitreous or aqueous tap sent for microbiologic sampling or into the no culture group if treated with immediate injection of intravitreal antibiotics with an anterior chamber paracentesis that was not sent for microbiologic sampling. The main outcome measures were visual acuity, the incidence of retinal detachment, and the need for additional procedures.

RESULTS

Of 165 endophthalmitis cases identified, 119 (72%) were in the culture group and 46 (28%) were in the no culture group. At endophthalmitis presentation, eyes in the culture group had a mean logMAR VA of 1.98 (∼20/1900) compared with 1.90 (∼20/1600) for eyes in the no culture group (P = .589). At the 6-month follow-up, the mean vision loss was 5.5 lines lost from baseline for the culture group compared with 2.5 lines lost for the no culture group (P = .017). Eyes in the culture group required a subsequent pars plana vitrectomy in 29 of 119 cases (24%) compared with 7 of 46 cases (15%) in the no culture group (P = .29). Six of 119 eyes (5%) in the culture group developed secondary retinal detachments compared with none in the no culture group (P = .143).

CONCLUSIONS

When access to microbiologic facility is not available, the management of postinjection endophthalmitis using intravitreal antibiotics without microbiologic cultures may be an acceptable treatment strategy.

Analysis of retinal detachment resulted from post-operative endophthalmitis treated with 23G pars Plana Vitrectomy

Background

To evaluate the rate, risk factors, functional outcome and prognosis in eyes with retinal detachment after post-operative endophthalmitis treated with 23G Pars Plana Vitrectomy.

Methods

Electronic patient files from 2009 until 2018 were screened for the presence of an endophthalmitis. Included were 116 eyes of 116 patients. This population was evaluated for the rate of retinal detachment after 23G Pars Plana Vitrectomy for endophthalmitis following cataract surgery or intravitreal injection. The main outcome measures were retinal detachment and visual acuity.

Results

The reasons for endophthalmitis were previous cataract surgery in 78 patients and following intravitreal injection in 38 patients. The first clinical evidence of endophthalmitis was present in median 5 days after the triggering intervention. Twenty-five eyes (21.55%) developed a retinal detachment an average of 25 days after endophthalmitis. RD is significantly associated with preoperative visual acuity (p = 0.001).

Conclusions

We emphasize the prognostic role of preoperative visual acuity in RD development of the endophthalmitis treated with 23G Pars Plana Vitrectomy.

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.

Rhegmatogenous Retinal Detachment in the Setting of Endophthalmitis: Risk Factors and Visual Outcomes

BACKGROUND AND OBJECTIVE

To investigate risk factors for rhegmatogenous retinal detachment (RRD) and visual acuity (VA) in eyes with RRD after developing endophthalmitis.

PATIENTS AND METHODS

Retrospective comparative study of 133 eyes with endophthalmitis at a tertiary center between 2009 and 2018. Demographics, exam findings, interventions, and outcomes were assessed. Cases of RRD within 6 months after onset of endophthalmitis were further analyzed.

RESULTS

Seventeen eyes (12.7%) with endophthalmitis developed RRD. Endogenous etiology was associated with higher rate of RRD (P = .038). Eyes that developed RRD had worse VA (20/3271) at 6 months (20/236; P = .001). Excluding the six eyes with macula-off RRD, VA for the remaining 11 eyes that developed RRD (20/1213) was similar to those without RRD (20/236; P = .095).

CONCLUSIONS

Endogenous etiology of endophthalmitis was associated with a higher rate of RRD. Eyes with successful RRD repair had outcomes similar to eyes that did not develop RRD. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:257-262.].

Retinal Detachment After Endophthalmitis: Risk Factors and Outcomes

Purpose

To analyze the risk factors, clinical course, and visual and anatomic outcomes of retinal detachment (RD) after endophthalmitis.

Patients and Methods

This retrospective study included 108 patients diagnosed with endophthalmitis between August 2014 and May 2019 at a single tertiary referral center. Sixteen patients developed RD after endophthalmitis. Retrospective analysis was performed to compare the cohort of endophthalmitis alone versus the cohort that developed RD after endophthalmitis, with analysis of potential risk factors for RD after endophthalmitis and treatment outcomes.

Results

The incidence of RD after endophthalmitis was 14.8% (N=16/108). The median time to develop RD after endophthalmitis was 27 days (range: 1-581 days, IQR: 25.3). Thirteen (81.3%) cases of RD occurred less than 2 months after the diagnosis of endophthalmitis. The incidence of aphakia (p=0.023) and posterior synechia (PS) (p=0.014) were significantly higher in the RD group. The mean initial and final visual acuity (VA) of the endophthalmitis alone group was 1.9±0.8 logMAR and 1.2±1.0 logMAR (p<0.0001), respectively, and 1.9±0.9 logMAR and 1.3±1.2 logMAR (p=0.07) in the RD group, respectively. Enucleation or evisceration occurred in 31.3% of cases with RD after endophthalmitis. The rate of final retinal re-apposition for the RD cohort was 56.3%.

Conclusion

The anatomic and functional outcomes for RD after endophthalmitis remain poor, with significant risk for permanent vision loss. Aphakia and posterior synechiae were seen more often in cases with RD after endophthalmitis.

Long-Term Effect of Silicone Oil Tamponade for Postoperative and Posttraumatic Bacterial Endophthalmitis

Purpose

To compare clinical features and microbial profiles, treatment outcomes, and prognostic factors of the eyes between postoperative and posttraumatic bacterial endophthalmitis after pars plana vitrectomy (PPV) with silicone oil (SO) tamponade.

Methods

Overall, 57 eyes of 57 patients who diagnosed exogenous bacterial endophthalmitis and underwent PPV with SO tamponade between 2000 and 2019 were reviewed. Causative microorganisms, culture positivity, change of mean best-corrected visual acuity (BCVA), and course of treatment were investigated between postoperative and posttraumatic groups, and relevant factors were analyzed according to the final BCVA.

Results

The mean BCVA change was not significantly different between groups. The positive rate of microorganisms was significantly higher in the postoperative group. The mean time to surgery over 48 hours, initial BCVA worse than hand motion, and additional surgery after initial vitrectomy were correlated with poor final BCVA worse than 20/200. There was significantly achieved final BCVA 20/200 or better in the Staphylococcus and Streptococcus group than the Enterococcus and Pseudomonas group.

Conclusion

PPV with SO tamponade may be an effective surgical treatment strategy for exogenous bacterial endophthalmitis. Final visual outcomes were not significantly different between postoperative and posttraumatic groups, and the mean time to surgery, initial visual acuity, additional surgery, and type of microorganism are significantly related to visual prognosis.

Rapid pathogen identification and antimicrobial susceptibility testing in in vitro endophthalmitis with matrix assisted laser desorption-ionization Time-of-Flight Mass Spectrometry and VITEK 2 without prior culture

PURPOSE

Prompt clinical diagnosis and initiation of treatment are critical in the management of infectious endophthalmitis. Current methods used to identify causative agents of infectious endophthalmitis are mostly inefficient, owing to suboptimal sensitivity, length, and cost. Matrix Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) can be used to rapidly identity pathogens without a need for culture. Similarly, automated antimicrobial susceptibility test systems (AST, VITEK 2) provide accurate antimicrobial susceptibility profiles. In this proof-of-concept study, we apply these technologies for the direct identification and characterization of pathogens in vitreous samples, without culture, as an in vitro model of infectious endophthalmitis.

METHODS

Vitreous humor aspirated from freshly enucleated porcine eyes was inoculated with different inocula of Staphylococcus aureus (S. aureus) and incubated at 37°C. Vitreous endophthalmitis samples were centrifuged and pellets were directly analyzed with MALDI-TOF MS and VITEK 2 without prior culture. S. aureus colonies that were conventionally grown on culture medium were used as control samples. Time-to-identification, minimum concentration of bacteria required for identification, and accuracy of results compared to standard methods were determined.

RESULTS

MALDI-TOF MS achieved accurate pathogen identification from direct analysis of intraocular samples with confidence values of up to 99.9%. Time from sample processing to pathogen identification was <30 minutes. The minimum number of bacteria needed for positive identification was 7.889x106 colony forming units (cfu/μl). Direct analysis of intraocular samples with VITEK 2 gave AST profiles that were up to 94.4% identical to the positive control S. aureus analyzed per standard protocol.

CONCLUSION

Our findings demonstrate that the direct analysis of vitreous samples with MALDI-TOF MS and VITEK 2 without prior culture could serve as new, improved methods for rapid, accurate pathogen identification and targeted treatment design in infectious endophthalmitis. In vivo models and standardized comparisons against other microbiological methods are needed to determine the value of direct analysis of intraocular samples from infectious endophthalmitis with MALDI-TOF MS and VITEK 2.

Antibiotics and antifungals in silicone oil

Background

Antimicrobials may be injected into silicone oil-filled eyes with endophthalmitis, but the interaction with oil is unclear. The purpose of the experiment is to determine whether vancomycin, amikacin, and amphotericin B mix with silicone oil.

Methods

Using the relative proportions of the human eye, 4 ml of 1000 centistokes silicone oil was centrifuged with 0.1 ml of vancomycin 1 mg/0.1 ml, amikacin 0.4 mg/0.1 ml, or amphotericin B 5 µg/0.1 ml in vitro and eluted. The aqueous was immediately analyzed with a liquid chromatographer/mass spectrometer and after 24 h.

Results

Within 24 h, a mean of 26.9 μmol/L of vancomycin, 0 nmol/L of amikacin, and 0 nmol/L of amphotericin B were recovered. When the concentrations of amikacin and amphotericin B were increased 100-fold, 0 nmol/L of amikacin and 75.7 µmol/L of amphotericin B were recovered.

Conclusions

Vancomycin and amphotericin B partially mixed with the silicone oil. Amikacin was not recovered from the antibiotic–silicone oil mixture.

Endophthalmitis: Then and Now

PURPOSE

To report historically evolving strategies (then and now) in prevention and management of endophthalmitis.

DESIGN

A perspective on relevant topics in the prophylaxis and management of endophthalmitis.

METHODS

This is an author-selected review of studies leading to changes in strategies for endophthalmitis management over the last 100 years.

RESULTS

The current perspective discusses the trends and strategies over the past century. Historically, 3 endophthalmitis time-periods have existed and include the pre-antimicrobial era, the predominantly systemic antimicrobial era, and the current intravitreal antimicrobial era. The management of endophthalmitis from different etiologies, including endogenous, postinjection, post-cataract surgery, and other anterior segment-related (eg, post-penetrating keratoplasty), bleb-associated, glaucoma drainage device-associated, and open globe injury-associated, are discussed. Specific etiologies may predict most common microbial causes and may guide differing management strategies. Pars plana vitrectomy offers theoretical advantages but is generally reserved for patients with more advanced disease.

CONCLUSIONS

Despite advances over the past 100 years, endophthalmitis is an important sight-threatening complication. Timely management with the appropriate use of antimicrobial agents may optimize visual outcomes.