Changes in ocular flora in eyes exposed to ophthalmic antibiotics

Vancomycin in infusion during vitrectomy in surgical treatment of acute postoperative and posttraumatic endophthalmitis

Background

Endophthalmitis is potentially devastating intraocular inflammation following eye trauma or surgery. We describe the visual outcomes and causative pathogens in acute bacterial postoperative and posttraumatic endophthalmitis treated with immediate pars plana vitrectomy (PPV) with Vancomycin dissolved in the infusion fluid.

Methods

Clinical records of consecutive 30 patients with postoperative endophthalmitis and 15 patients with posttraumatic endophthalmitis were evaluated. Vancomycin was administered constantly in the infusion fluid at the time of complete PPV. Cultures were prepared from anterior chamber paracentesis. The mean follow-up period was 13 months.

Results

The visual acuities were improved in 38 cases (84 %) and remained stable in seven cases (16 %). Median post-PPV visual acuity was 1.0 logMAR in a group with postoperative endophthalmitis and 1.3 logMAR in a group with posttraumatic endophthalmitis (p < 0.05). Twenty cases (44 %) were culture-positive (Staphylococcus, Streptococcus, Enterococcus and Bacillus spp).

Conclusions

Early PPV with Vanomycin in infusion leads to vision improvement in patients with both posttraumatic and postoperative endophthalmitis. In our series of 45 cases culture was positive only in half of the cases.

Adherence to European Society for Cataract and Refractive Surgery Recommendations among Italian Cataract Surgeons: A Survey

Purpose

To survey the surgical routines with regards to prophylactic strategies in a sample of Italian hospitals and compare these with European Society for Cataract and Refractive Surgery (ESCRS) guidelines.

Methods

Six private and 18 public hospitals were included in this clinical-based retrospective study. The overall volume of cataract operations in the 24 centers in 2013 was 43,553. Main outcome measure was incidence of endophthalmitis per 1,000. An incidence of less than 0.13% was considered acceptable.

Results

Our study provides the first Italian data on the use of intracameral antibiotics in cataract surgery as recommended by the ESCRS. Thirteen centers (54%) used intracameral cefuroxime at the end of surgery. Of the 13 centers that used cefuroxime, 8 (62%) had an incidence of endophthalmitis less than 0.13%. Of the 7 (29%) centers that did not use intracameral cefuroxime, all had an endophthalmitis rate of greater than 0.13%. This difference was statistically significant (p<0.05). Among the 4 centers not included, 2 used vancomycin in the infusion bottle, 1 a fluoroquinolone, and the last a combination of antibiotics. The majority of surgeons (71%) used preoperative antibiotic eyedrops, but this measure was not shown to be significantly protective.

Conclusions

Slightly more than half of the centers surveyed in this study adhered to the recommendations of the ESCRS and routinely employed prophylactic intracameral cefuroxime. An incidence of endophthalmitis greater than 0.13% was encountered significantly more frequently among centers that did not employ intracameral cefuroxime.

Molecular and Phenotypic Characterization of Staphylococcus epidermidis Isolates from Healthy Conjunctiva and a Comparative Analysis with Isolates from Ocular Infection

Staphylococcus epidermidis is a common commensal of healthy conjunctiva and it can cause endophthalmitis, however its presence in conjunctivitis, keratitis and blepharitis is unknown. Molecular genotyping of S. epidermidis from healthy conjunctiva could provide information about the origin of the strains that infect the eye. In this paper two collections of S. epidermidis were used: one from ocular infection (n = 62), and another from healthy conjunctiva (n = 45). All isolates were genotyped by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec), detection of the genes icaA, icaD, IS256 and polymorphism type of agr locus. The phenotypic data included biofilm production and antibiotic resistance. The results displayed 61 PFGE types from 107 isolates and they were highly discriminatory. MLST analysis generated a total of 25 STs, of which 11 STs were distributed among the ocular infection isolates and lineage ST2 was the most frequent (48.4%), while 14 STs were present in the healthy conjunctiva isolates and lineage ST5 was the most abundant (24.4%). By means of a principal coordinates analysis (PCoA) and a discriminant analysis (DA) it was found that ocular infection isolates had as discriminant markers agr III or agr II, SCCmec V or SCCmec I, mecA gene, resistance to tobramycin, positive biofilm, and IS256⁺. In contrast to the healthy conjunctiva isolates, the discriminating markers were agr I, and resistance to chloramphenicol, ciprofloxacin, gatifloxacin and oxacillin. The discriminant biomarkers of ocular infection were examined in healthy conjunctiva isolates, and it was found that 3 healthy conjunctiva isolates [two with ST2 and another with ST9] (3/45, 6.66%) had similar genotypic and phenotypic characteristics to ocular infection isolates, therefore a small population from healthy conjunctiva could cause an ocular infection. These data suggest that the healthy conjunctiva isolates do not, in almost all cases, infect the eye due to their large genotypic and phenotypic difference with the ocular infection isolates.

Endophthalmitis following intravitreal anti-vascular endothelial growth factor (VEGF) injection: a comprehensive review

The purpose of this review is to report and summarize previously reported studies and assess many of the individual steps of the intravitreal injection procedure's possible effect on the prevention of endophthalmitis. The pooled endophthalmitis rate from 20 large retrospective case series of anti-VEGF injections was 144/510,396 (0.028%; 1/3,544). Injections may be performed in an office-based location or in an operating room (OR) and low rates of endophthalmitis can be achieved in either location with careful attention to asepsis. Pre- or post-injection topical antibiotics have not been shown to be effective, and could select for more virulent microorganisms. Povidone-iodine prior to injection is accepted as the gold-standard antiseptic agent, but aqueous chlorhexidine may be an alternative. Antisepsis before and after gel or subconjunctival anesthetic is suggested. The preponderance of Streptococcal infections after intravitreal injection is discussed, including the possible role of aerosolization, which can be minimized by using face masks or maintaining silence. As with other invasive procedures in medicine, the use of sterile gloves, following adequate hand antisepsis, may be considered. Control of the eyelashes and lid margin is required to avoid contamination of the needle, but this can be achieved with or without a speculum. Techniques to minimize vitreous reflux have not been shown to reduce the risk of endophthalmitis. Same day bilateral injections should be performed as two separate procedures, preferably using drug from different lots, especially when using compounded drugs.

Postinjection endophthalmitis in the comparison of age-related macular degeneration treatments trials (CATT)

OBJECTIVE

To describe the incidence and outcomes of endophthalmitis after intravitreal injections of anti-vascular endothelial growth factor agents in the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT) and to assess the effect of prophylactic topical antimicrobials on incidence.

DESIGN

Cohort study within a randomized clinical trial.

PARTICIPANTS

Patients enrolled in CATT.

METHODS

Patients with neovascular age-related macular degeneration received intravitreal injections of ranibizumab or bevacizumab under 1 of 3 dosing regimens. The study protocol specified preinjection preparation to include use of a sterile lid speculum and povidone iodine (5%). Use of preinjection and postinjection antibiotics was at the discretion of the treating ophthalmologist. Patients were followed up monthly for 2 years.

MAIN OUTCOME MEASURES

Development of endophthalmitis and visual acuity.

RESULTS

Endophthalmitis developed after 11 of 18 509 injections (1 per 1700 [0.06%]; 95% confidence interval, 0.03%-0.11%), and in 11 of 1185 patients (0.93%; 95% confidence interval, 0.52-1.66). Incidence of endophthalmitis was 0.15% among injections with no antibiotic use, 0.08% among injections with preinjection antibiotics only, 0.06% among injections with postinjection antibiotics only, and 0.04% among injections with preinjection and postinjection antibiotics (P = 0.20). All eyes were treated with intravitreal antibiotics and 4 underwent vitrectomy. Among the 11 affected eyes, the final study visual acuity was 20/40 or better in 4 eyes (36%), 20/50 to 20/80 in 2 eyes (18%), 20/100 to 20/160 in 3 eyes (27%), and worse than 20/800 in 2 eyes (18%). The final visual acuity was within 2 lines of the visual acuity before endophthalmitis in 5 eyes (45%).

CONCLUSIONS

Rates of endophthalmitis were low and similar to those in other large-scale studies. Use of topical antibiotics either before or after injection does not seem to reduce the risk for endophthalmitis.

Effects of moxifloxacin exposure on the conjunctival flora and antibiotic resistance profile following repeated intravitreal injections

AIM

To evaluate the effects of moxifloxacin exposure on the conjunctival flora and antibiotic resistance profile following repeated intravitreal injections.

METHODS

Seventy-two eyes of 36 patients [36 eyes in control group, 36 eyes in intravitreal injection (IVI) group] were enrolled in the study. All the eyes had at least one IVI and had diabetic macular edema (DME) or age-related macular degeneration (ARMD). Moxifloxacin was prescribed to all the patients four times a day for five days following injection. Conjunctival cultures were obtained from the lower fornix via standardized technique with every possible effort made to minimize contamination from the lids, lashes, or skin. Before the application of any ophthalmic medication, conjunctival cultures were obtained from both eyes using sterile cotton culture. An automated microbiology system was used to identify the growing bacteria and determine antibiotic sensitivity.

RESULTS

The bacterial cultures were isolated from 72 eyes of 36 patients, sixteen of whom patients (44.4%) were male and twenty (55.6%) were female. Average age was 68.4±9.0 (range 50-86). The average number of injections before taking cultures was 3.1+1.0. Forty-eight (66.7%) of 72 eyes had at least one significant organism. There was no bacterial growth in 8 (20.5%) of IVI eyes and in 16 (44.4%) of control eyes (P=0.03). Of the bacteria isolated from culture, 53.8% of coagulase negative staphylococci (CoNS) in IVI eyes and 47.2% CoNS in control eyes. This difference between IVI eyes and control eyes about bacteria isolated from culture was not statistically significant (P=0.2). Eleven of 25 bacteria (44.0%) isolated from IVI eyes and 11 (57.9%) of 19 bacteria isolated from control eyes were resistant to oxacillin. The difference in frequency of moxifloxacine resistance between two groups was not statistically significant (12.0% in IVI eyes and 21.1% in control eyes) (P=0.44). There were no cases of resistance to vancomycin, teicoplanin and linezolid.

CONCLUSION

There was no difference in species of bacteria isolated from cultures, or in the frequency of resistance to antibiotics between eyes that had recurrent IVI followed by moxifloxacin exposure compared with control eyes. However, the number of eyes that had bacterial growth was higher in IVI group than in the control group.

Prevention and treatment of injection-related endophthalmitis

BACKGROUND

Intravitreal injections are the fastest growing cause of endophthalmitis and can result in severe vision loss. The prevention, diagnosis and management of such infections remain unclear and at times controversial.

METHODS

We searched Pubmed for keywords "prophylaxis," "endophthalmitis," "intravitreal injection." We focused on studies published in the last 2 years as well as other recent studies with particular attention to data on the incidence, microbiology, prevention, and treatment of injection-related endophthalmitis.

RESULTS

Over 20 relevant studies were found. With povidone-iodine preparation, the per-injection endophthalmitis rate is low at about 0.03%. Antibiotics do not appear to be beneficial for prevention of post-injection endophthalmitis. The best timing of vitrectomy is unclear.

CONCLUSIONS

Antibiotic prophylaxis is probably not needed when giving intravitreal injections. More data is needed to help determine the proper treatment for post-injection endophthalmitis.