Cases Of Postoperative Endophthalmitis Research Articles

Endophthalmitis following cataract surgery and effect of different intracameral antibiotic regimes in Sweden 2011 - 2017. A national registry study.

To study the incidence, predictive factors, aetiology and visual consequences of postoperative endophthalmitis (PE) in relation to three intracameral antibiotic regimes. Swedish National Cataract Register (NCR) entries from 2011 through 2017. Observational retrospective study. PE incidence, influencing factors, bacteriology and visual outcome were analyzed with regard to the three major prophylactic IC protocols. The overall incidence of PE was 0.023% or 177 cases in 764 513 cataract procedures. Analyzed per intracameral regime, the rates of PE were 0.024% (126 cases in 514 916 surgeries) for cefuroxime, 0.020% (25 cases in 122 340 surgeries) for moxifloxacin and 0.017% (20 cases in 121 045 surgeries) for combined cefuroxime-ampicillin. Incidences were not statistically significantly different from one another. Gram-positive bacteria caused 89.0% of culture positive cases. Enterococci as pathogens were significantly more frequent with intracameral cefuroxime than with moxifloxacin, p = 0.006 or cefuroxime-ampicillin, p < 0.001, while streptococci other than enterococci were more common with moxifloxacin than with cefuroxime, p < 0.001. Bacterial susceptibility to the given antibiotics was demonstrated in 21.3% of PE cases treated with cefuroxime, which was statistically significantly lower than proportions found with cefuroxime-ampicillin, 60.0%, p = 0.015, or with moxifloxacin, 88.2%, p < 0.001. Visual outcome worse than 20/200 were similar in the groups ranging from 42.0% to 53.7%. No statistically significant differences in PE incidence or visual outcome results between treatment groups were demonstrated. However, differences in aetiology and bacterial sensitivity were found between the prophylactic intracameral treatments.

Comparison of Efficacy and Safety between Immediate Sequential and Delayed Sequential Bilateral Cataract Surgery

Purpose: We compared the efficacy and safety of immediate sequential bilateral cataract surgery (ISBCS) and delayed sequential bilateral cataract surgery (DSBCS).Methods: We analyzed the best corrected visual acuity (BCVA), spherical equivalent (SE), and mean absolute error (MAE) in the ISBSC and DSBSC groups. The study population comprised 72 patients (144 eyes) who underwent ISBCS and 92 patients (184 eyes) who underwent DSBCS at Seoul St. Mary's Hospital between January 2019 and December 2021.Results: At 1 month postoperatively, the ISBCS group demonstrated a BCVA, SE, and MAE of 0.11 ± 0.09, -0.33 ± 0.42 diopters (D), and 0.38 ± 0.32 D, respectively; similarly, the DSBCS group exhibited a BCVA, SE, and MAE of 0.11 ± 0.15, -0.29 ± 0.56 D, and 0.41 ± 0.43 D, respectively. Furthermore, no significant differences were observed between the ISBCS and the DSBCS groups regarding SE and MAE at the 1-month follow-up for the first and second operated eyes. No cases of postoperative endophthalmitis and toxic anterior segment syndrome were reported.Conclusions: ISBCS is an effective and cost-effective approach that yields favorable postoperative outcomes when performed by an experienced surgeon supported by appropriate pre- and postoperative care, particularly in patients who demonstrate good cooperation.

Modified-dropless protocol (nil intraocular) for micro-incision vitrectomy surgery (MIVS): a retrospective pilot study

BackgroundPerioperative infection and inflammation prophylaxis after ocular surgery has evolved over the years along with improvements in surgical equipment and a growing interest in alternatives to the standard topical eye drops. The purpose of this study is to evaluate the outcomes of a novel, modified-dropless protocol for 23-gauge (23-G), 25-gauge (25-G) and 27-gauge (27-G) micro-incision vitrectomy surgery (MIVS) that omits any intraocular injections of antibiotics or steroids.MethodsThis Institutional Review Board-approved, single-surgeon retrospective study reviewed MIVS post-surgical outcomes in patients who received a modified-dropless protocol from February 2020 to March 2021. A total of 158 charts were reviewed, of which 150 eyes met the eligibility criteria. After each case, patients were administered a 0.5 cc subconjunctival injection of a 1:1 Cefazolin (50 mg/cc):Dexamethasone (10 mg/cc) in the inferior fornix and 0.5 cc of posterior Sub-Tenon’s Kenalog (STK). No intravitreal injections were administered, and no pre- or postoperative antibiotic or steroid eye drops were prescribed. For patients allergic to penicillin, separate subconjunctival injections of 0.25 cc each of Vancomycin (10 mg/cc) and Dexamethasone (10 mg/cc) were administered. The primary safety parameter was postoperative cases of endophthalmitis. Secondary endpoints consisted of Best-Corrected Distance Visual Acuity (BCVA), intraocular pressure (IOP), and postoperative complications (retinal detachments, inflammation, need for additional surgery) within three months of surgery. Statistical analysis was performed using chi-square (χ²) tests for categorical values, and a Student’s t-test to compare continuous outcomes.ResultsThe majority of surgeries (96%) were performed with the 27G MIVS platform. There were no cases of postoperative endophthalmitis. Mean logMAR BCVA improved from 0.71 (± 0.67) to 0.61 (± 0.60) post-operatively (p = 0.02). Excluding patients who had silicone oil tamponade, postoperative BCVA improved from 0.67 (± 0.66) to 0.54 (± 0.55) (p = 0.003). Mean IOP increased from 14.6 (± 3.8) to 15.3 (± 4.1) (p = 0.05). Ten patients required further medication therapy for an increase in IOP, one had inflammatory signs, and 14 required a second surgical intervention mostly due to recurrences of initial surgical indication.ConclusionA modified-dropless postoperative protocol involving subconjunctival and posterior sub-Tenon’s injections only may be a safe and convenient alternative to topical eye drops for patients undergoing MIVS, but additional and larger studies are needed.

Анализ случаев послеоперационных эндофтальмитов по данным Кировской офтальмологической больницы

The aim of the work was to analyze the features of the etiopathogenesis of postoperative endophthalmitis and to develop an algorithm for the actions of doctors of various structural units when making a diagnosis. Material and methods. For 5 years from 2018 to 2022, 10 cases of postoperative endophthalmitis were recorded in the Kirov Clinical Ophthalmological Hospital: 4 after cataract surgery, 4 after intravitreal injections, 1 after posterior vitrectomy, 1 after plastic filtration cushion. Results. Our clinic has developed an algorithm that prescribes the actions of doctors upon admission of a patient diagnosed with endophthalmitis. The patient is immediately hospitalized for urgent indications, intravitreal administration of vancomycin 0.1 ml and ceftazidim 0.1 ml is performed, 0.1 ml is taken from the vitreal cavity for sowing. The patient is prescribed conservative anti-inflammatory, antibacterial treatment. According to the indications, vitreoretinal surgery is performed up to 6 hours after diagnosis. Conclusion. Endophthalmitis, despite the successes achieved in the development of ophthalmology, remains a serious disease with difficult to predict treatment results. This pathology requires timely and effective treatment to ensure satisfactory visual results. Keywords: postoperative endophthalmitis, treatment algorithm

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

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

A case of postoperative Sphingomonas paucimobilis endophthalmitis after parsplana vitrectomy

We report a case of acute onset of postoperative endophthalmitis following pars plana vitrectomy, in a healthy middle-aged male person, caused by Sphingomonas paucimobilis, a gram-negative bacillus widely distributed in the environment and reported to cause opportunistic infection in immunocompromised. The case showed complete resolution on vitrectomy and intravitreal antibiotics. The bacillus was multi-drug resistant, showing resistance to all known commonly used antibiotics except intermediate sensitivity to meropenem. There have been two reported cases of postoperative endophthalmitis caused by Sphingomonas paucimobilis following cataract surgery, but this is the first reported case following pars plana vitrectomy.

Spectrum of signs, symptoms, and treatment in amphotericin B-resistant Trichosporon endophthalmitis: A series of ten cases of post-cataract surgery cluster endophthalmitis.

The aim of this study was to present the signs, symptoms, management, and outcome of a series of cases of cluster endophthalmitis caused by a multi-drug resistant fungus, Trichosporon. This was a retrospective, non-randomized, consecutive interventional case series. Ten cases of postoperative endophthalmitis operated by a surgeon on three consecutive operation theater (OT) days presented 3-5 months after their surgery. All cases were microbiologically confirmed. The pathogen was found to be resistant to most antifungals, including amphotericin B. The cases had a latent period of around 45 days. Management of endophthalmitis included intravitreal injections, anterior chamber (AC) lavage, Pars Plana vitrectomy (PPV), posterior capsulotomy, IOL, and capsular bag removal. Multiple intravitreal injections were required due to recurrence of infections after initial improvement with voriconazole injections. Structural integrity was maintained and infection-free status was achieved in all the eyes. The presenting vision ranged from 6/60 to PL (perception of light). Seven out of 10 had improvement in their final vision over the presenting vision. Final outcome of four patients had vision of 6/24 or better, 4 patients had vision in the range of 2/60 to 6/36 and 2 patients had PL. Trichosporon can cause devasting infections even in the immunocompetent, especially in association with implants and catheters. Triazoles form the mainstay of treatment of Trichosporon infection due to the high susceptibility of the organism in vitro. A regimen including voriconazole and amphotericin B may prove to be the most effective. This is the first report of an outbreak of cluster endophthalmitis caused by Trichosporon.

Clinical features of endophthalmitis clusters after cataract surgery and practical recommendations to mitigate risk: systematic review.

Intraocular transmission of exogenous pathogens in cataract surgery can lead to endophthalmitis. This review evaluates the features of endophthalmitis clusters secondary to pathogen transmission in cataract surgery. Articles reporting on pathogen transmission in cataract surgery were identified via searches of Ovid MEDLINE, EMBASE, and Cochrane CENTRAL, and a total of 268 eyes from 24 studies were included. The most common source of infectious transmission was attributed to a contaminated intraocular solution (ie, irrigation solution, viscoelastic, or diluted antibiotic; n = 10). Visual acuity at presentation with infectious features was 1.89 logMAR (range: 1.35 to 2.58; ∼counting fingers) and 1.33 logMAR (range: 0.04 to 3.00; Snellen: ∼20/430) at last follow-up. Patients with diabetes had worse outcomes compared with patients without diabetes. The most frequently isolated pathogen from the infectious sources was Pseudomonas sp. (50.0%). This review highlights the various routes of pathogen transmission during cataract surgery and summarizes recommendations for the detection, prevention, and management of endophthalmitis clusters.

Comparison of different endophthalmitis prophylactic measures in cataract surgery - An analysis of 2.4 lakh cases.

To compare different endophthalmitis prophylaxis methods adopted in cataract surgery (manual small-incision cataract surgery and phacoemulsification) between the years 2013 and 2021 in the community eye care section of a tertiary eye care hospital in South India and report their outcomes. All cataract surgeries performed from January 2013 to December 2021 (2,46,874 surgeries) at a single center were included in this retrospective study. The different endophthalmitis rates with each regimen were analyzed and evaluated. 70,081 surgeries were performed from January 2013 to February 2015, where Tobramycin was added to Balanced Salt Solution (BSS) (Group A). From March 2015 to January 2017, 63,245 surgeries were performed when intracameral Moxifloxacin was given (Group B). From February 2017 to December 2021, 1,13,548 surgeries were performed were Amikacin was added to BSS (Group C). In total, 42 cases of postoperative endophthalmitis were reported during the study period (0.02%). There was no significant difference in the endophthalmitis rates between groups A and B (P = 0.4152); however, there was a significant decrease in endophthalmitis rates in group C when compared with group A (P = 0.04) and group B (P = 0.006). There was a significant reduction in the rates of endophthalmitis following the addition of amikacin in irrigating BSS. Nocardia was one of the predominant organisms isolated from these endophthalmitis patients. This is the first single-center study to report a comparative analysis of different endophthalmitis prophylactic measures in a community eye care set up with a high incidence of Nocardia endophthalmitis prevented with amikacin in BSS irrigating solution.

Development of topical chitosan/ β-glycerophosphate-based hydrogel loaded with levofloxacin in the treatment of keratitis: An ex-vivo study

Staphylococcus species are responsible for most cases of post-operative endophthalmitis. Topical ocular drug was applied for post-operative infection prevention, but the way of delivery encounters many challenges in terms of patient's compliance, drug efficacy, and drug penetration. We used the levofloxacin-loaded chitosan/gelatin/β-glycerophosphate hydrogel sustained releasing system with good in vitro anti-bacterial efficacy and biocompatibility, which we had previously designed, for ex vivo keratitis model to test the preclinical drug efficacy and to determine drug level in the anterior chamber of the eye. The result showed that the ex-vivo corneal keratitis model with S. aureus infection revealed mild opacity over the central cornea with stromal infiltrate, but without obvious stromal infiltration post levofloxacin-loaded hydrogel treatment after 24 h of infection. Quantification of viable bacteria showed a significant anti-bacterial activity. The histological evidence also showed no visible S. aureus after levofloxacin-loaded hydrogel treatment, with a significant anti-inflammatory effect. We also examined the drug concentration in the aqueous humor 24 h after instilling one drop of the levofloxacin-loaded hydrogel. The concentration achieved to a desired drug level. These results suggested that by the ex-vivo model, levofloxacin-loaded hydrogel can be applied for treatment in post-operative endophthalmitis or keratitis after the ophthalmic surgery.

Novel Postoperative Dropless Protocol for Micro-Incision Vitrectomy Surgery.

To evaluate the outcomes of a novel postoperative dropless protocol for 25-gauge and 27-gauge micro-incision vitrectomy surgery (MIVS). The institutional review board approved a single-center, retrospective study. A total of 493 surgeries were identified, and 451 cases from 369 patients met eligibility criteria. Instead of pre- or postoperative drops, patients were given a novel postoperative dropless protocol consisting of subconjunctival injections of a 1:1 cefazolin:dexamethasone mix at each sclerotomy and intravitreally, and injection of posterior sub-Tenon's Kenalog. Primary outcome measure was cases of postoperative endophthalmitis. There was one presumed case of endophthalmitis. Anterior chamber paracentesis sample was negative for culture and Gram stain. For all patients, mean logMAR best-corrected visual acuity improved from 0.65 (±0.69) to 0.57 (±0.61) postoperatively (P = 0.004). Mean intraocular pressure increased from 14.5 (±4.3) to 15.5 (±4.8) postoperatively (P < 0.001). Mean follow-up was 96 days. This novel postoperative dropless protocol could potentially be a convenient alternative to topical eye drops for patients undergoing MIVS, but further study is required to establish its safety. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:587-592.].

A 27 - Gauge Microincision Vitrectomy Surgery for Posterior Segment Diseases in a Tertiary Centre, Nepal

Introduction: Transconjunctival micro incision vitrectomy surgery (MIVS) with 23 or 25 gauge instrumentation is more advantageous than traditional 20 gauge surgery. We intended to evaluate the visual outcome, complications and indication of various vitreoretinal diseases using 27 Gauge vitrectomy systems. &#x0D; Methods: This study was a prospective, interventional, non-comparative study conducted in Nepal Eye Hospital from June 2017 to July 2018. Fifty-two patients with various vitreoretinal diseases were recruited. The main outcome measures included corrected distance visual acuity (CDVA) preoperative and postoperative, intraocular pressure (IOP) preoperative and postoperative, indication for vitreoretinal surgery, intraoperative complications, and postoperative complications.&#x0D; Results: Fifty two eyes of 52 patients (26 men and 26 women; mean age, 59 years) underwent 27-gauge pars planavitrectomy. Surgical indications included epiretinal membrane (n = 11), full-thickness macular hole (n = 11), rhegmatogenous retinal detachment [n = 14 (12 vitrectomy only and two vitrectomy with scleral buckle)], vitreous haemorrhage (n = 3), vitreous opacities (n = 3), silicon oil removal (n = 3), proliferative diabetic retinopathy [n = 6 (5 vitreous haemorrhage and one tractional retinal detachment)], posterior IOL dislocation (n = 1). Postoperative complications included transient ocular hypertension in eight eyes (15.39%), transient hypotony in five eyes (9.62%) and vitreous haemorrhage in five eyes (9.62%). No cases of postoperative endophthalmitis, sclerotomy - related tears, or choroidal detachments were encountered in the follow-up period. Mean corrected distance visual acuity improved from 20 / 796 (logarithm of the minimum angle of resolution, 1.60 ± 0.64) preoperatively to 20 / 49 (logarithm of the minimum angle of resolution, 0.42 ± 0.26) postoperatively (p = 0.000,) at final follow up.&#x0D; Conclusions: 27-gauge micro-incision vitrectomy surgery was found to be a safe and effective suture-less surgery with favourable outcomes, in terms of vision.

Is zero incidence of postoperative endophthalmitis after cataract surgery achievable

Purpose: For over 10 years, there have been zero cases of postoperative endophthalmitis (POE) after cataract surgery at Chatswood Private Hospital (CPH), Sydney, Australia. Study design: We conducted a retrospective audit study to evaluate the reasons for this, as well as the different preferences for route of antibiotic prophylaxis used. Methods: Deidentified data on cataract surgery cases for 2010–2020 were extracted and analyzed descriptively. Results: A total of 28,937 cataract surgery cases were performed at CPH from 2010-2020, for which no cases of POE were identified. The intracameral route for antibiotic prophylaxis was more commonly used compared to subconjunctival or both. Conclusion: Administration of prophylactic antibiotics, regardless of the route of administration, is beneficial and equally effective in preventing POE. Having operating theatres dedicated to ophthalmology helps maintain high standards of sterility of instrumentation and operating environments.

Postoperative Endophthalmitis in Immediate Sequential Bilateral Cataract Surgery: A Nationwide Registry Study

To report the incidence of postoperative endophthalmitis (PE) after immediate sequential bilateral cataract surgery (ISBCS) in Sweden. Retrospective cohort registry study. Patient data from 1 457 172 cataract extractions, including 1 364 934 unilateral surgeries and 92 238 ISBCSs. Endophthalmitis cases reported to the Swedish National Cataract Register (NCR) during a 16-year period (2002-2017) were analyzed in comparison to all control cases with regard to patient characteristics, surgical technique, and capsule complication. Incidence and determinants for PE in ISBCS compared with unilateral surgeries. A total of 422 cases of PE were identified in 1 457 172 cataract extractions, yielding an overall incidence of 0.029% (95% confidence interval [CI], 0.0262-0.0317). For unilateral procedures, the rate was 0.0299% (95% CI, 0.0270-0.0328) or 408 cases in 1 364 934 operations, whereas that for ISBCS was 0.0152% (95% CI, 0.0072-0.0231) or 14 incidents in 92 238 operations (P= 0.01). In a logistic regression model including all cataract procedures, nonuse of intracameral (IC) antibiotics (ABs), capsule complication, age 85 years or more, male gender, and ocular comorbidity were found to be independent risk factors for PE. All these parameters were less frequent in ISBCS. Notwithstanding, in the same multivariate analysis, ISBCS in itself was associated with asignificantly lower risk for PE. At follow-up, 5 of the 14 PE cases in the ISBCS cohort had a visual acuity (VA) of 20/200 or worse. Of these, one 93-year-old ISBCS patient developed bilateral infection. After ISBCS in Sweden, PE occurred once in 6600 surgeries. The risk of sustaining a final VA of 20/200 or less was 1 incident in 18 000 operated eyes. When counseling potential ISBCS patients about the risk of PE, it seems reasonable to state that the reported risk in the literature is lower than that with unilateral surgery but not negligible. Precautions remain necessary.

Efficacy and Side Effects of Intracameral Moxifloxacin as Prophylaxis after Cataract Surgery

Purpose: To determine the efficacy of intracameral moxifloxacin at the end of cataract surgery.&#x0D; Methods: Retrospective record based study. Study was based on a consecutive case series of patients who had cataract surgery during 2009 through 2019 in the Department of Ophthalmology at Maharishi Vashishth State Medical College, Basti (India). Intracameral preservative free moxifloxacin injection was given at the conclusion of surgery to most patients. Standardized operating room and sterilization protocols were used. All The medical records were reviewed for the 8 weeks after surgery. Post-operative endophthalmitis rate was computed using the number of cases of postoperative endophthalmitis as the numerator and the number of cataract surgeries as the denominator.&#x0D; Results: Of the 10,108 surgeries performed during study period, 2012 (19.9%) involved intracameral moxifloxacin injection. No adverse drug reactions were reported from administration of intracameral antibiotics during the study period. The post-operative endophthalmitis rate in patient who had not received intracameral antibiotic injection was 0.06%. There was no endophthalmitis case reported in patients who had received intracameral moxifloxacin injection as prophylaxis.&#x0D; Conclusion: The results of this study support the use if intracameral moxifloxacin as a routine prophylaxis for endophthalmitis after cataract surgery. Especially in rural setting as the patients postoperative instruction compliance is poor and many patients are lost to follow-ups sue to different reasons.

Twenty years of endophthalmitis: Incidence, aetiology and clinical outcome.

To review the incidence, aetiology and outcomes of endophthalmitis during a 20-year period in a Norwegian university hospital. Single-centre retrospective review. Medical records of all patients admitted to Stavanger University Hospital with suspected endophthalmitis between January 1999 and December 2018 were reviewed. We identified 84 eyes of 81 patients. Postoperative endophthalmitis (PE) was seen in 64 eyes (76%), endogenous endophthalmitis in thirteen eyes (15%), trauma in four eyes (5%) and three eyes (4%) had keratitis-associated endophthalmitis. Administration of intravitreal injections (IVI) was the most common cause (30%), followed by cataract surgery (CS) (21%). Of 40238 IVI, 23 PE cases were identified (incidence, 0.057%; 95% confidence interval [CI] 0.036-0.086%). Of 39697 CS, 12 PE cases were identified (incidence, 0.030%; 95%CI 0.016-0.053%). After introduction of intracameral cefuroxime PE incidence after CS decreased from 0.10% in 1999-2003 to 0.015% in 2004-2018 (p=0.003). Eighty-four per cent of organisms were Gram-positive. Coagulase-negative staphylococci accounted for 54% of culture-proven cases, and 89% of post-IVI culture-proven cases. Thirty eyes (36%) either regained their previous vision or lost ≤1 Early Treatment Diabetic Retinopathy Study line. One third of endophthalmitis cases had a favourable visual outcome of logMAR 0.2 or better. PE after IVI occurred in 1 in 1750 procedures, and was the most common cause of PE. The incidence of PE after CS has decreased >sixfold since 2003, to 1 in 6700 surgeries. A high proportion of low-virulence bacterial species may have contributed to the favourable visual outcome.

Confusion bias and seasonal variation of exogenous endophthalmitis incidence.

We read with interest the study by Kim et al. in which they analyzed postoperative endophthalmitis incidences in South Korea from July 2014 to June 2017.1 A total of 951 (0.064%) of 1 498 548 cataract procedures were identified as presumed postoperative endophthalmitis cases. The researchers found that rates were higher in July, during the summer months and when relative humidity and the precipitation level were also higher. The differences in incidence among seasons were statistically significant. It has been known for decades, and more recently confirmed, that the microorganisms that cause postoperative endophthalmitis usually come from the patient's own conjunctival and eyelid flora that enters the eye through the incision during the procedure or within a short time span after the procedure.2–4 Therefore, as the authors commented, the reason as to why postoperative endophthalmitis showed seasonal variation is not straightforward. Many variables could play a role, but undoubtedly it could also have been the result of a confusion bias, leading to an overestimation of the actual association with the summer time. The difficulty lies in identifying that third variable (confounding factor) that was not controlled. Possibly pertinent questions in this regard would be as follows: do all clinics operate throughout the year, or some close during the summer? Is it possible that those that close during the summer time have different prophylaxis protocols (v.gr. intracameral antibiotics) and/or the incidence of endophthalmitis in those clinics that do not operate during the summer was much lower throughout the year?5 Do the same surgeons perform surgeries in summer, or are more procedures performed by surgeons in training during that time? Is the rate of intraoperative complications the same during the summer? Is there an influx of patients who are going to have surgery in South Korea, coming from other countries, during the summer? The exclusion of these possible confounding factors would serve to strengthen the finding of a real association between the incidence of acute postoperative endophthalmitis and the seasons of the year. Further studies would be required to confirm some of the possible explanations suggested by the researchers: for example, that the conjunctival flora is different. Preoperative cultures of patients undergoing cataract surgery could be performed throughout the year, which would generate valuable information. On another note, a false inference can be made when information at the collective or group level is incorrectly assumed at the individual level. This would imply a multilevel analysis, the environmental variables being the contextual ones. The association under study had to consider the hierarchical structure of the data, both individually and collectively to avoid the occurrence of an ecological fallacy. The huge sample size also attracted our attention. With almost 1.5 million observations, it is very easy to find statistically significant bivariate associations, which can be spurious (ie, lacking authenticity or validity). The association is not synonymous with causation. A rigorous multivariate analysis would be required, and the variables of the model should not only be included based on purely mathematical criteria but also based on causality criteria, to respect the principle of parsimony.

Virulence Factors of Bacteria Related to Ocular Infections in Non Immunocompromised Patients: Review Article

The ocular surface is constantly exposed to pathogenic bacteria. Many Gram positive and Gram negative bacteria have been implicated in ocular infections, in non immunocompromised patients, causing severe vision impairment. These microorganisms have in their quiver a variety of arrows to cause infection. The aim of this study is to list the virulence factors of the main ocular pathogens. Data were extracted from PubMed and Google Scholar. <i>S. aureus</i> and <i>Streptococci, Bacillus cereus</i> and <i>Corynebacterium (non-diphtheriae)</i> are the main culprits as far as Gram positive bacteria are concerned. <i>S. aureus</i> causes infections of the lacrimal apparatus, cornea and eyelids, conjunctivitis, keratitis, and endophthalmitis. <i>Streptococcus pneumoniae, Streptococcus pyogenes, Enterococcus</i> and <i>Streptococcus viridians</i> are isolated from post injection endophthalmitis cases. S. pneumoniae</i> is most involved in keratitis, conjunctivitis, and endophthalmitis. <i>Streptococcus pyogenes</i> is most involved in blepharitis and hospital acquired conjunctivitis in neonates in the intensive care unit. <i>Enterococcus faecalis</i> is implicated in postoperative endophthalmitis cases. <i>Corynebacterium (non-diphtheriae) species</i> are involved mainly in infections complicating cataract surgery, keratoplasty, and vitrectomy. <i>Bacillus species</i> provoke conjunctivitis, keratitis and post-traumatic endophthalmitis. <i>Bacillus cereus</i> can cause rapidly destructive endophthalmitis. Among Gram negative bacteria, <i>Neisseria gonorrhoeae, Pseudomonas aeruginosa, Chlamydia trachomatis</i>, and <i>Bartonella species</i> are major ocular pathogens, responsible for severe ocular damage. Gonococcal conjunctivitis (GC) is still a cause of blindness in some developing countries. When it occurs in neonates, it is called gonococcal ophthalmia neonatorum. <i>P. aeruginosa</i> is related to contact lens-associated keratitis. <i>Chlamydia trachomatis</i> is the culprit of trachoma and inclusion conjunctivitis. <i>Bartonella henselae</i> causes bartonellosis or cat scratch disease, or cat scratch fever. Eye infection includes optic neuropathy and neuroretinitis. When the eye is the primary site of inoculation, the patients are diagnosed with Parinaud oculo-glandular syndrome (infection of the conjunctiva, eyelid and adjacent skin with regional lymphadenopathy). Chronic <i>Bartonella</i> infection provokes blurred vision, photophobia and eye irritation. Comprehension of the mechanism of infection, caused by these pathogens, is crucial in diagnosis and treatment.

Cap-puncturing mechanism for ophthalmic postoperative antibiotic eye drops: friend or foe?

A retrospective case series highlights two cases of postoperative endophthalmitis, in which similar improper technique of puncturing the antibiotic bottle with a nonsterile needle was noted.&#x0D; Patient A, a 65-year-old man with three weeks’ history of uneventful combined cataract and pars plana vitrectomy (PPV) presented with acute painful right eye and vision blurring from 6/12 to 1/60 for two days. Examination showed severe anterior chamber activity and hazy fundal view. B-scan showed dense vitritis. Vitreous sampling revealed gram positive cocci, but no culture growth. Patient B, a 69-year-old man presented with three days’ history of right painful red eye and vision dropped to light perception following an uneventful cataract surgery. Examination showed severe anterior chamber activity with hypopyon, raised intraocular pressure, and no fundal view. B-scan detected dense vitritis with loculation. Vitreous sampling cultured Pseudomonas aeruginosa in Patient B. In both cases, the patients reported piercing the generic topical ciprofloxacin 0.3% bottle tip with a nonsterile needle instead of the prescribed method of using the sterile, inner aspect of the bottle cap. However, the cultures of the bottle contents were negative in both cases. Both patients received intravitreal, topical, and systemic antibiotics and subsequently underwent PPV. Patient A recovered vision to baseline, while Patient B recovered to counting finger vision.&#x0D; The cap-puncturing mechanism for eye drop bottles is designed to maintain the sterility of the contents. However, this may backfire when patients do not understand the prescribed technique. We postulate that this improper technique predisposed the two cases to endophthalmitis.

Outcomes of 27G(+) transconjunctival sutureless vitrectomy for posterior segment disease

Objective: To report the clinical outcomes and safety profile of 27G(+) transconjunctival sutureless vitrectomy (TSV) in eyes with posterior segment disease. Methods: Prospective, interventional case series. Eyes undergoing 27G(+) TSV for a vitreoretinal surgery indication were included from Dec 2015 to Mar 2016. Change in visual acuity and occurrence of intraoperative and postoperative complications with minimum follow-up of 6 weeks were recorded. Results: Eighty-three eyes met the inclusion criteria. Surgical indications included epiretinal membrane (n=27), proliferative diabetic retinopathy (n=17), full-thickness macular hole (n=11), rhegmatogenous retinal detachment with or without proliferative vitreoretinopathy (PVR) (n=8), vitreous hemorrhage(n=7), vitreous opacities (n=7), diabetic macular edema non-response to anti-VEGF agents(n=4), intraocular lens or cataract nucleus dropped into vitreous cavity (n=2). Mean follow-up was 19 weeks (range 6-34 weeks). Visual acuity improved in all cases. The cutter incarcerated with trocar in a vitreous hemorrhage case. There were no other intraoperative complications and no case required sutured at the conclusion of surgery. Postoperative complications included transient ocular hypertension in 2 eyes (2.4%) and transient hypotony in 1 eye (1.2%). No cases of postoperative endophthalmitis, sclerotomy related retinal tears, or choroidal detachments were encountered in the follow-up period. Conclusion: The 27G(+) TSV was effective and safe for varied surgical indications with low rates of intraoperative and postoperative complications. (Chin J Ophthalmol, 2018, 54:918-922).