Innovative cold atmospheric plasma (iCAP) decreases corneal ulcer formation and bacterial loads and improves anterior chamber health in methicillin resistant Staphylococcus aureus keratitis.

Bacterial keratitis is a vision-threatening infection of the cornea that is typically treated with antibiotics. However, antibiotics sometimes fail to eradicate the infection and do not prevent or repair the damage caused directly by the bacteria or the host immune response to the infection. Our group previously demonstrated that treatment of Pseudomonas aeruginosa keratitis in rabbits with innovative cold atmospheric plasma (iCAP) resulted in reduced edema, ulcer formation, and bacterial load. In this study, we investigated the efficacy of iCAP treatment in methicillin-resistant Staphylococcus aureus (MRSA). New Zealand white rabbits were infected intrastromally with MRSA then treated with iCAP, moxifloxacin, vancomycin, or combination of iCAP with each antibiotic to assess the safety and efficacy of iCAP treatment compared to untreated controls and antibiotics. iCAP treatment significantly reduced bacterial loads and inflammation, improved anterior chamber clarity, and prevented corneal ulceration compared to untreated controls and antibiotic treatment. Safety assessments of grimace test scores and tear production showed that iCAP was not significantly different from either antibiotic treatment in terms of distress or tear production. Combination iCAP/antibiotic treatment did not appear to provide significant added benefit over iCAP alone. Our findings suggest that the addition of iCAP may be a viable tool in reducing damage to the cornea and anterior chamber of the eye following S. aureus keratitis.

An X-ray inactivated vaccine against Pseudomonas aeruginosa Keratitis in mice.

Pseudomonas aeruginosa (P. aeruginosa) is one of the most prevalent pathogens of bacterial keratitis. Bacterial keratitis is a major cause of blindness worldwide. The rising incidence of multidrug resistance of P. aeruginosa precludes treatment with conventional antibiotics. Herein, we evaluated the protective efficiency and explored the possible underlying mechanism of an X-ray inactivated vaccine (XPa) using a murine P. aeruginosa keratitis model. Mice immunized with XPa exhibit reduced corneal bacterial loads and pathology scores. XPa vaccination induced corneal macrophage polarization toward M2, averting an excessive inflammatory reaction. Furthermore, histological observations indicated that XPa vaccination suppressed corneal fibroblast activation and prevented irreversible visual impairment. The potency of XPa against keratitis highlights its potential utility as an effective and promising vaccine candidate for P. aeruginosa.

ASCRS clinical advisory on intracameral moxifloxacin injection for infection prophylaxis.

Moxifloxacin solution is frequently injected at the conclusion of cataract surgery for endophthalmitis prophylaxis. 2 different concentrations are most commonly available in the United States for intracameral (IC) use: 0.5% (5 mg/mL) and 0.1% (1 mg/mL). The recommended volume to be injected is different for the 2 concentrations, and incorrect dosing can increase the risk of toxic anterior segment syndrome or endophthalmitis. In addition, the U.S. Food and Drug Administration recently published an alert regarding potential adverse events associated with intraocular compounded moxifloxacin. This clinical advisory reviews the optimal dosing of IC moxifloxacin based on current evidence.

Legal obligation in the general population: face mask influence on endophthalmitis after intravitreal injection.

PURPOSE: To investigate whether compulsory face masking in public life changes the incidence or pattern of post-injection endophthalmitis (PIE). PATIENTS AND METHODS: All injections of bevacizumab, ranibizumab, aflibercept, dexamethasone or triamcinolone between 01/01/2015 and 12/31/2021 at the University Eye Clinic of Tuebingen were included in this retrospective analysis. The injection procedure itself was unchanged since 2015 and included the use of a sterile drape covering the head up to the shoulders which prevents airflow toward the eye. Furthermore, all staff wore a face mask and gloves at all times. The two study periods were defined by the introduction of a compulsory face masking rule in public life (01/01/2015 until 04/27/2020 vs. 04/28/2020 until 12/31/2021). RESULTS: A total of 83,543 injections were performed in the tertiary eye clinic, associated with a total of 20 PIE (0.024%, 1/4177 injections). Of these, thirteen PIE were documented during the pre-pandemic period (0.021%, 1/4773 injections) and seven PIE during the pandemic period (0.033%, 1/3071 injections). No significant difference in PIE risk was observed (p = 0.49), and there was no case of oral flora associated PIE. CONCLUSION: Although some potential confounders (wearing time, skin flora) could not be considered, there was no clear signal that the introduction of compulsory face masking in public life did alter the risk for PIE in our patient population. Three and six months after PIE, no difference in visual acuity was detectable between the two study periods.

Tannin coordinated nanozyme composite-based hybrid hydrogel eye drops for prophylactic treatment of multidrug-resistant Pseudomonas aeruginosa keratitis.

Pseudomonas aeruginosa infection is a severe acute suppurative ulcer that engulfs virtually the entire tissue in a short period and leads to devastating destruction. Antibiotic therapy is a common approach for the prophylaxis and treatment of P. aeruginosa infection. However, it is often associated with serious side effects, complications, and multidrug resistance. Therefore, it has been a long-standing challenge to explore safe and effective methods for controlling P. aeruginosa infection. Herein, tannin-coordinated nanozyme composite-based hybrid hydrogels (TCNH) are developed and characterized for the prophylactic treatment of P. aeruginosa and multidrug-resistant P. aeruginosa infections using mouse keratitis as the animal model. The TCNH eye drops are constructed by photoinitiated free radical polymerization of acetylated gelatin solution containing self-synthesized tannin-coordinated Co3O4/Ag nanozyme composite. The as-prepared TCNH displays good dispersibility, peroxidase-like activity and in vitro/in vivo biocompatibility. The nanozyme composite in TCNH seems to penetrate the interior of bacteria and exhibited significant broad-spectrum antibacterial activity owing to its intrinsic and nanozymic catalytic properties. Furthermore, TCNH eye drops can be successfully applied to treat P. aeruginosa and multidrug-resistant P. aeruginosa keratitis. The findings of this study reveal the potential of tannin-coordinated nanozyme composite-based hybrid hydrogel eye drops for treating infectious diseases.

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

Purpose: 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. Methods: 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. Results: 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). Conclusion: 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.

EFFECT OF PHYSICIAN FACE MASK USE ON POSTINJECTION ENDOPHTHALMITIS.

PURPOSE: To examine the impact of physician face mask use on the rates and outcomes of postinjection endophthalmitis. METHODS: A multicenter retrospective, comparative cohort study comparing endophthalmitis rate and visual acuity of eyes that developed endophthalmitis after antivascular endothelial growth factor injections at Mayo Clinic Rochester (MCR) and at Mayo Clinic Health System sites depending on physician masking. RESULTS: A total of 164,824 injections were performed at MCR and Mayo Clinic Health System sites. Of these, 66,098 injections were in the no mask group and 98,726 injections were in the mask group. Overall, there were no differences in the rates of infectious endophthalmitis in the no mask versus mask cohorts (overall: no mask: 20 cases [0.0303%] vs. mask: 41 cases (0.0415%); P = 0.24; infectious: no mask: 12 cases [0.018%] versus mask: 13 cases [0.0132%]; P = 0.42). At MCR alone, there was a significant reduction in infectious endophthalmitis between the no mask versus mask groups (no mask: 9 cases [0.0297%] versus mask: 2 cases [0.003%]; P < 0.001). Only 2 cases of infectious endophthalmitis occurred at MCR after the face mask policy was implemented (1 in 30,000 injections). At presentation and at 6 months, the average visual acuity was similar for patients who developed endophthalmitis between the no mask versus mask groups. CONCLUSION: Physician face mask use did not affect the rate or outcome of postinjection endophthalmitis. However, there was a significant reduction at MCR after masking along with other quality improvement measures, including performance of injections in a dedicated procedure room and preparation of patients by nurses, that led to a low rate of endophthalmitis.

Conjunctival sac bacterial culture of patients using levofloxacin eye drops before cataract surgery: a real-world, retrospective study.

BACKGROUND: The use of antibiotics preoperatively is effective to decrease the incidence of ocular bacterial infections but may lead to high resistance rate, especially on patients with multi-risk clinical factors. This study systematically analyzed real-world data (RWD) of patients to reveal the association between clinical factors and conjunctival sac bacterial load and offer prophylaxis suggestions. METHODS: We retrieved RWD of patients using levofloxacin eye drops (5 mL: 24.4 mg, 4 times a day for 3 days) preoperatively. Retrieved data included information on the conjunctival sac bacterial culture, sex, presence of hypertension and diabetes mellitus (DM), and history of hospital-based surgeries. Data was analyzed using SPSS 24.0. RESULTS: RWD of 15,415 cases (patients) were retrieved. Among these patients, 5,866 (38.1%) were males and 9,549 (61.9%) females. 5,960 (38.7%) patients had a history of hypertension, and 3,493 (22.7%) patients had a history of DM. 7,555 (49.0%) patients had a history of hospital-based operations. There were 274 (1.8%) positive bacterial cultures. Male patients with hypertension and DM may be at increased risk of having positive bacterial cultures (P < 0.05). Staphylococcus epidermidis (n = 56, 20.4%), Kocuria rosea (n = 37, 13.5%), and Micrococcus luteus (n = 32, 11.7%) were the top 3 isolated strains. Most bacterial strains were resistant to various antibiotics except rifampin, and 82.5% (33 of 40 isolates) of Staphylococcus epidermidis isolates had multidrug antibiotic resistance. Numbers of culture-positive Staphylococcus epidermidis isolates in the male group and non-DM group were greater than those in the female and DM groups, respectively. Micrococcus luteus (n = 11, 8.8%) was found less frequently in non-hypertension group than in hypertension group. CONCLUSION: Sex (Male) and the presence of hypertension and DM are risk factors for greater conjunctival sac bacterial loads. We offer a prophylactic suggestion based on the combined use of levofloxacin and rifampin. However, this approach may aggravate risk of multidrug resistance.

Effect of resolvin D1 on experimental bacterial keratitis to prevent corneal scar.

PURPOSE: The study aims to investigate the role of the lipid mediator resolvin D1 (RvD1) in bacterial keratitis in a murine model. METHODS: The effect of RvD1 on Pseudomonas aeruginosa-stimulated human corneal epithelial cells (HCECs) and mouse macrophages and dendritic cells (DCs) was assessed. C57BL/6 mouse corneas were abraded and treated with RvD1 after stimulation with P. aeruginosa, following which cytokine production level in the cornea and drainage lymph nodes was compared with that in controls. Corneal opacity and thickness were assessed using anterior segment photographs, and optical coherence tomography and corneal infiltrates were analyzed using immunohistochemistry for neutrophils. RESULTS: RvD1 significantly inhibited pro-inflammatory cytokine production in HCECs, mouse macrophages, and DCs. Corneal opacity and corneal thickness were reduced, and the development of corneal infiltrates, specifically neutrophils, was also significantly inhibited by RvD1 in response to stimulation with P. aeruginosa. CONCLUSIONS: RvD1 inhibits P. aeruginosa-induced corneal inflammation. This finding supports a potential therapeutic approach for patients with bacterial keratitis.

Intracameral Bacteriophage Injection as Postoperative Prophylaxis for Enterococcus faecalis-Induced Endophthalmitis After Cataract Surgery in Rabbits.

Purpose: Post-cataract surgery bacterial endophthalmitis is a serious postoperative complication, and Enterococcus spp.-induced endophthalmitis reportedly has a particularly poor visual prognosis. This study aimed to demonstrate the prophylactic effect of postoperative intracameral phage administration in Enterococcus faecalis-induced endophthalmitis after cataract surgery in rabbits. Methods: Endophthalmitis was induced in rabbits by injecting E. faecalis into the anterior chamber just after lensectomy while simultaneously administering either phage phiEF24C-P2 or vehicle. Retinal function was evaluated using electroretinography. The number of viable bacteria and myeloperoxidase (MPO) activity in the eye and histopathologic examinations were analyzed 48 hours after infection. Results: In the vehicle-treated group, retinal function at 24 hours after infection was impaired, and the number of viable bacteria and MPO activity in the eye increased 48 hours later. In the phage-administered group, retinal function was maintained; the number of viable bacteria and MPO activity were significantly suppressed. Histopathologic examinations showed disruption of the retinal layers and the presence of numerous E. faecalis in the lens capsule and vitreous cavity in vehicle-treated eyes. In contrast, retinal structures were intact, and no E. faecalis staining was observed in phage-treated eyes. No retinal dysfunction was observed in the group that received phage only without lensectomy; almost no phage was detected in the eyes after 14 days of treatment. Conclusions: Phage administration in the anterior chamber did not cause retinal dysfunction and suppressed postoperative endophthalmitis in rabbits. Translational Relevance: In vivo results of intracameral phage administration suggest that phages are a promising prophylactic candidate for postoperative endophthalmitis.

Antibiotic prophylaxis of postoperative endophthalmitis after cataract surgery: results of the 2021 ASCRS member survey.

In an online survey of >1200 global cataract surgeons, 66% were using intracameral (IC) antibiotic prophylaxis. This compared with 50% and 30% in the 2014 and 2007 surveys, respectively. Irrigation bottle infusion and intravitreal injection was each used by only 5% of respondents. For IC antibiotics, vancomycin was used by 6% in the United States (52% in 2014), compared with 83% for moxifloxacin (31% in 2014). Equal numbers used compounded moxifloxacin or the Vigamox bottle as the source. There was a decrease in respondents using preoperative (73% from 85%) and postoperative (86% from 97%) topical antibiotic prophylaxis; the latter was not used by 24% of surgeons injecting IC antibiotics. Reasons cited by those not using IC antibiotics include mixing/compounding risk (66%) and being unconvinced of the need (48%). However, 80% believe having a commercially approved IC antibiotic is important; if reasonably priced, this would increase adoption of IC prophylaxis to 93%.