Prospective randomized comparison of 1-day versus 3-day application of topical levofloxacin in eliminating conjunctival flora

Antibiotics versus placebo for acute bacterial conjunctivitis

BACKGROUND

Acute bacterial conjunctivitis is an infection of the conjunctiva and is one of the most common ocular disorders in primary care. Antibiotics are generally prescribed on the basis that they may speed recovery, reduce persistence, and prevent keratitis. However, many cases of acute bacterial conjunctivitis are self-limited, resolving without antibiotic therapy. This Cochrane Review was first published in The Cochrane Library in 1999, then updated in 2006, 2012, and 2022.

OBJECTIVES

To assess the benefits and side effects of antibiotic therapy in the management of acute bacterial conjunctivitis.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2022, Issue 5), MEDLINE (January 1950 to May 2022), Embase (January 1980 to May 2022), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.

CLINICALTRIALS

gov), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases in May 2022.   SELECTION CRITERIA: We included randomized controlled trials (RCTs) in which any form of antibiotic treatment, with or without steroid, had been compared with placebo/vehicle in the management of acute bacterial conjunctivitis. This included topical and systemic antibiotic treatments.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed the titles and abstracts of identified studies. We assessed the full text of all potentially relevant studies and determined the included RCTs, which were further assessed for risk of bias using Cochrane methodology. We performed data extraction in a standardized manner and conducted random-effects meta-analyses using RevMan Web.

MAIN RESULTS

We included 21 eligible RCTs, 10 of which were newly identified in this update. A total of 8805 participants were randomized. All treatments were topical in the form of drops or ointment. The trials were heterogeneous in terms of their eligibility criteria, the nature of the intervention (antibiotic drug class, which included fluoroquinolones [FQs] and non-FQs; dosage frequency; duration of treatment), the outcomes assessed and the time points of assessment. We judged one trial to be of high risk of bias, four as low risk of bias, and the others as raising some concerns. Based on intention-to-treat (ITT) population, antibiotics likely improved clinical cure (resolution of clinical symptoms or signs) by 26% (RR 1.26, 95% CI 1.09 to 1.46; 5 trials, 1474 participants; moderate certainty) as compared with placebo. Subgroup analysis showed no differences by antibiotic class (P = 0.67) or treatment duration (P = 0.60). In the placebo group, 55.5% (408/735) of participants had spontaneous clinical resolution by days 4 to 9 versus 68.2% (504/739) of participants treated with an antibiotic. Based on modified ITT population, in which participants were analyzed after randomization on the basis of positive microbiological culture, antibiotics likely increased microbiological cure (RR 1.53, 95% CI 1.34 to 1.74; 10 trials, 2827 participants) compared with placebo at the end of therapy; there were no subgroup differences by drug class (P = 0.60). No study evaluated the cost-effectiveness of antibiotic treatment. Patients receiving antibiotics had a lower risk of treatment incompletion than those in the placebo group (RR 0.64, 95% CI 0.52 to 0.78; 13 trials, 5573 participants; moderate certainty) and were 27% less likely to have persistent clinical infection (RR 0.73, 95% CI 0.65 to 0.81; 19 trials, 5280 participants; moderate certainty). There was no evidence of serious systemic side effects reported in either the antibiotic or placebo group (very low certainty). When compared with placebo, FQs (RR 0.70, 95% CI 0.54 to 0.90) but not non-FQs (RR 4.05, 95% CI 1.36 to 12.00) may result in fewer participants with ocular side effects. However, the estimated effects were of very low certainty.

AUTHORS' CONCLUSIONS

The findings of this update suggest that the use of topical antibiotics is associated with a modestly improved chance of resolution in comparison to the use of placebo. Since no evidence of serious side effects was reported, use of antibiotics may therefore be considered to achieve better clinical and microbiologic efficacy than placebo. Increasing the proportion of participants with clinical cure or increasing the speed of recovery or both are important for individual return to work or school, allowing people to regain quality of life. Future studies may examine antiseptic treatments with topical antibiotics for reasons of cost and growing antibiotic resistance.

Change in Nationwide Incidence of Post-Cataract Surgery Endophthalmitis: Korean Cohort Study from 2002 to 2013

Purpose: To investigate the change in nationwide incidence of endophthalmitis following cataract surgery in Korea from 2002 to 2013. Methods: From a national sample cohort (n = 1 025 340), cases of postoperative endophthalmitis between 2002 and 2013 were identified. Results: From 70,719 cases of cataract surgery, 49 incidents of endophthalmitis were reported, yielding an incidence of 0.069% (95% confidence interval [CI], 0.051-0.092%). Overall, the endophthalmitis incidence decreased from 0.103% in 2002-2005 to 0.045% in 2010-2013, corresponding to an annually decreasing time-trend (0.902, 95% CI, 0.827-0.984). In diabetic patients, however, the incidence was 0.128% and did not change (time trend, 1.015; 95% CI, 0.828-1.245). Conclusions: This study revealed the incidence of endophthalmitis decreased during a 12-year period, but remained constant in diabetic patients.

Relationship between anesthesia and postoperative endophthalmitis: A retrospective study

Previous study showed that patients under general anesthesia (GA) had nasopharyngeal secretions on the face at the end of ocular surgery, especially in propofol-based total intravenous anesthesia (TIVA), it might induce postoperative endophthalmitis. Therefore, we conducted a retrospective study to compare the incidence of endophthalmitis after ocular surgery under topical, inhalation anesthesia, and propofol-based TIVA in our medical center from 2011 to 2015.A total of 21,032 patients were included, and we evaluated epidemiologic factors, systemic diseases, other ocular pathologic characteristics, complications during the surgery, technique of ocular surgery, method of antibiotic prophylaxis, vitreous culture, and vision outcome in these patients.Fifteen endophthalmitis cases among 21,032 operations reported, equaling an incidence of 0.071%. The incidence rates under topical, inhalation anesthesia, and propofol-based TIVA were 0.083%, 0.039%, and 0%, respectively (P = 0.39). Moreover, the risk of endophthalmitis under GA (0.024%) was significantly lower than topical anesthesia (0.083%) (P < 0.001). We also found that elder was the risk factor for endophthalmitis following ocular surgery.In conclusion, propofol-based TIVA or inhalation anesthesia did not increase the risk of endophthalmitis after ocular surgery. Thus, GA was not a risk factor for postoperative endophthalmitis. By contrast, elder was the risk factor for postoperative endophthalmitis.

Optimal Duration for the Use of 0.5% LevofloxacinEye Drops Before Vitreoretinal Surgery

PURPOSE

To investigate various regimens of prophylactic antibiotic therapy for vitreoretinal surgery.

DESIGN

This study compared different prophylactic therapies with 0.5% levofloxacin eye drops.

METHODS

Two hundred nine patients from 7 hospitals scheduled to undergo vitreoretinal surgery were randomized into 3 groups to receive 0.5% levofloxacin eye drops for 1 day (6 times/d), 2 days (3 times/d), or 3 days (3 times/d) before surgery (groups 1D, 2D, and 3D, respectively). all patients received 3 applications of levofloxacin eye drops at 15-minute intervals beginning 1 hour before surgery and conjunctival sac disinfection with 5.0% povidone-iodine 15 minutes before surgery. conjunctival swabs were cultured before levofloxacin therapy (T0), on the morning of surgery (T1), after povidone-iodine disinfection (T2), immediately after surgery (T3), 1 day postoperatively (T4), and 1 week postoperatively (T5).

RESULTS

The positive bacterial culture rates in groups 1D, 2D, and 3D fell, respectively, from 37.33%, 30.77%, and 31.88% at t0 to 10.67%, 12.31%, and 11.59% at t1 and 1.33%, 0%, and 0% at T2. at each time point (T0-T5), there were no significant differences among the groups in positive bacterial culture rate. the bacterial eradication rates in groups 1D, 2D, and 3D were, respectively, 100%, 94.74%, and 90.00% at T1 (after levofloxacin) and 100% in all groups at T2 (after povidone-iodine).

CONCLUSIONS

The efficacy of levofloxacin in preventing postoperative infection was similar in the 3 treatment groups. it is recommended that 0.5% levofloxacin be used for only 1 day before vitreoretinal sur-gery (6 times/d) to minimize the use of prophylactic antibiotics.

Perioperative Antibiotics to Prevent Acute Endophthalmitis after Ophthalmic Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Post-operative endophthalmitis is a rare and dreaded complication in ophthalmic operations because it often induces irreparable vision loss. Although many ophthalmological studies aimed at reducing the rate of endophthalmitis have been performed around the world, controversy continues to surround some issues, including the choice of antimicrobials and their route of administration, duration and timing. The aim of this study is to investigate some of these unresolved issues.

METHODS

A systematic review and meta-analysis of randomized controlled trials and observational studies was performed. The PubMed, EMBASE, Cochrane Library and Clinical Trials databases were searched to identify studies published until Feb. 2016. The relative risk (RR) for each clinical outcome data is presented with 95% confidence intervals (CIs). Pooled estimates of effects were calculated using random-effect models.

RESULTS

Thirty-four studies from twenty-four reports involving 1264797 eyes were included in this analysis. Endophthalmitis occurred, on average, in one out of 6177 eyes when intracameral vancomycin/moxifloxacin were used and in one out of 1517 eyes when intracameral vancomycin/moxifloxacin were not used. The relative risk (95% CI) of endophthalmitis was reduced to 0.20 (0.10, 0.42) when intracameral antibiotics were used (p<0.0001). The subconjunctival injection of antibiotics was not superior to other administration routes included in this study (RR = 1.67, 95% CI (0.55, 5.05), p = 0.36). A statistically significant difference was found in the rate of endophthalmitis between the use and lack of use of topical antibiotics (RR = 0.65, 95% CI (0.43, 0.99), p = 0.04). However, no statistically significant difference was found in microbial isolation rates between these groups (RR = 0.77, 95% CI (0.34, 1.75), p = 0.53). When long-term and short-term use of topical antibiotics before surgery were compared, a statistically significant difference was found in microbial isolation rates (RR = 0.57, 95% CI (0.44, 0.74), p<0.0001).

CONCLUSIONS

This meta-analysis concluded intracameral antibiotics are effective at preventing endophthalmitis in ocular surgery. A randomized controlled trial confirms the efficacy of cefuroxime but recent large cohort studies support the efficacy of vancomycin/moxifloxacin intracamerally. Intracameral antibitoics are superior to subconjunctival injections but that irrigation antibitoic data are not of enough quality to make a comparison. Different results were found in two clinical outcomes between the use or lack of use of topical antibiotic therapy, we did not find sufficient evidence to conclude that its use prevents endophthalmitis.

Endophthalmitis After Intravitreal Injections in Patients With Self-reported Iodine Allergy

PURPOSE

To present cases of endophthalmitis following intravitreal injections where povidone-iodine (PI) was not used as part of the surgical preparation.

DESIGN

Retrospective case series.

METHODS

All cases of presumed injection-related endophthalmitis presenting to the Massachusetts Eye and Ear Infirmary between June 2008 and November 2014 and Dean McGee Eye Institute between January 2010 and January 2015 were identified. Patients who did not receive PI preparation owing to documented self-reported allergy to iodine, iodine-containing contrast material, or shellfish were identified and their injection histories and clinical courses reviewed.

RESULTS

The combined rate of postinjection endophthalmitis at these 2 centers was 0.019%. Among 42 patients with postinjection endophthalmitis, 5 (11.9%) did not receive PI prophylaxis. The mean number of intravitreal injections without PI before the development of endophthalmitis was 10.6 with a 9.4% rate of endophthalmitis (5 cases per 53 injections). All patients underwent tap-and-inject procedures with vancomycin 1 mg and ceftazidime 2 mg. Two patients did not receive PI at the time of tap and inject; 1 of these patients required subsequent pars plana vitrectomy for worsening clinical course. Cultures were positive in 4 of 5 cases; all positive cultures grew coagulase-negative Staphylococcus. All patients who received subsequent intravitreal injections received PI prophylaxis without allergic reactions, thus demonstrating a lack of true PI allergy.

CONCLUSIONS

Avoiding PI owing to self-reported iodine "allergy" risks substantial ocular morbidity. Allergy testing can be pursued per patient request or in rare cases of suspected true PI allergy; however, in cases where delayed treatment would adversely affect visual outcome, the clinician should feel confident that minimal allergic risk exists.

Comparison of the efficacy of povidone-iodine 1.0%, 5.0%, and 10.0% irrigation combined with topical levofloxacin 0.3% as preoperative prophylaxis in cataract surgery

PURPOSE

To compare the efficacy of povidone-iodine 1.0%, 5.0%, and 10.0% in combination with topical levofloxacin 0.3% in reducing the preoperative conjunctival bacterial load before cataract surgery.

SETTING

Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany.

DESIGN

Randomized clinical trial.

METHODS

This study enrolled patients scheduled for cataract surgery between July 2010 and January 2011. All patients received topical levofloxacin 0.3% 4 times on the preoperative day and were randomly assigned to these study groups: Group 1 (povidone-iodine 1.0%), Group 2 (povidone-iodine 5.0%), and Group 3 (povidone-iodine 10.0%). In all groups, the conjunctiva was flush irrigated with 10 mL of povidone-iodine of the respective concentration. Conjunctival specimens were obtained at 4 timepoints: baseline (no-surgery eye), before povidone-iodine irrigation, after povidone-iodine irrigation, and at the end of surgery. All specimens were inoculated onto blood and chocolate agars and into thioglycolate broth.

RESULTS

The study was completed by 271 patients. In the control smear (no-surgery eye), no significant difference in positive cultures was found. After 10 mL povidone-iodine irrigation, a considerable reduction in the conjunctival bacterial load occurred in all groups. The difference in positive cultures was statistically significant between Group 1 and Group 3 (P=.024) and between Group 2 and Group 3 (P=.029). Coagulase-negative Staphylococcus was the most commonly isolated bacteria in all groups.

CONCLUSION

Povidone-iodine 10.0% was more effective than povidone-iodine 1.0% and 5.0% in decreasing the conjunctival bacterial load before surgery.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Six-year incidence of endophthalmitis after cataract surgery: Swedish national study

PURPOSE

To report the nationwide incidence and risk factors for endophthalmitis after cataract surgery in Sweden.

SETTING

Swedish National Cataract Register containing reports on cataract operations from all Swedish ophthalmic surgical units.

DESIGN

Prospective epidemiologic study.

METHODS

Endophthalmitis case reports were collected from 2005 through 2010. Case and control parameters pertaining to patient characteristics and surgical technique were generated from the database. In addition, information from annual surveys regarding the topical prophylactic protocol was analyzed.

RESULTS

The reports showed 135 endophthalmitis cases in 464,996 operations, equaling an incidence of 0.029%. Patient age over 85 years, perioperative communication with the vitreous and, above all, nonuse of intracameral cefuroxime showed a statistically significant association with endophthalmitis in the logistic regression. Short-term topical antibiotics given as add-on prophylaxis to the intracameral regimen before, after, or before and after the operation did not confer a clear-cut benefit. Groups with topical treatment were small, comprising 14% of the sample.

CONCLUSIONS

The incidence of endophthalmitis after cataract surgery in Sweden is declining, which appears to be explained by a fall in the frequency of major risk factors. Operating earlier in the cataract course, avoiding capsule breakage, and giving intracameral antibiotics universally should further reduce the endophthalmitis rate.

[Bacterial contamination of needles after intravitreal injection in Paraguay]

PURPOSE

The study was designed to prospectively evaluate the bacterial contamination of needles used for intravitreal injection during surgery.

MATERIAL AND METHODS

Between December 2007 and December 2010, 549 eyes of 413 patients were treated with intravitreal injections of 1.25 mg bevacizumab. Of the patients 322 received a single injection and 91 multiple injections. Preoperatively the periorbital skin of all patients was treated with 10% povidone iodine (PVI) and the conjunctival sac was irrigated with 1% PVI. No pre-injection antibiotics were administered. Immediately after the injection the needles were rinsed 3 times in thioglycolate broth which was then cultured at 37°C for 5 days. As a negative control 73 sterile unused needles were treated in the same way.

RESULTS

Out of the 549 needle points tested 8 (1,45%) were found to be contaminated after intravitreal injections. The isolated bacteria were coagulase negative Staphylococcus (n = 7), Propionibacterium acnes (n = 1) and Klebsiella pneumoniae (n = 1) (co-contamination in one case).

CONCLUSION

Contamination of needles is minimal after prophylactic povidone iodine irrigation before intravitreal injections. Therefore, this prophylaxis technique is recommended before intravitreal injections in order to prevent postoperative infections.

Antibiotics versus placebo for acute bacterial conjunctivitis

BACKGROUND

Acute bacterial conjunctivitis is an infection of the conjunctiva. Both the palpebral and the bulbar ocular conjunctival surfaces are usually affected and typically become red and inflamed. Antibiotic therapy is widely used for the treatment of acute bacterial conjunctivitis. This Cochrane Review was first published in The Cochrane Library in 1999; updated in 2006 and again in 2012.

OBJECTIVES

To assess the benefits and harms of antibiotic therapy in the management of acute bacterial conjunctivitis.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 7), MEDLINE (January 1950 to July 2012), EMBASE (January 1980 to July 2012), OpenGrey (System for Information on Grey Literature in Europe) (www.opengrey.eu/), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 18 July 2012.

SELECTION CRITERIA

We included double-masked randomised controlled trials (RCTs) in which any form of antibiotic treatment had been compared with placebo/vehicle in the management of acute bacterial conjunctivitis. This included topical, systemic and combination (for example, antibiotics and steroids) antibiotic treatments.

DATA COLLECTION AND ANALYSIS

Two authors (UN and SM) independently checked and reviewed the titles and abstracts of identified studies. We assessed the full text of all potentially relevant studies. We graded the included RCTs for methodological quality using Cochrane methodology. We performed data extraction in a standardised manner. We performed random-effects meta-analyses using RevMan.

MAIN RESULTS

We identified 11 eligible RCTs which randomised a total of 3673 participants. One further trial, which was published in abstract form in 1990 but has yet to be reported fully, is currently 'awaiting assessment'. Six of the 11 included studies have been included for the first time in this latest (2012) update. The trials were heterogeneous in terms of their inclusion and exclusion criteria, the nature of the intervention, and the outcome measures assessed. We judged two of the trials to be of high quality and graded the remainder as poor quality.Meta-analyses of data on clinical and microbiological remission rates revealed that topical antibiotics were of benefit in improving 'early' (days two to five) clinical (risk ratio (RR) 1.36, 95% confidence interval (CI) 1.15 to 1.61) and microbiological (RR 1.55, 95% CI 1.37 to 1.76) remission rates. At the 'late' time point (days six to 10), antibiotics were found to still confer modest benefits in clinical remission (RR 1.21, 95% CI 1.10 to 1.33) and microbiological cure rates (RR 1.37, 95% CI 1.24 to 1.52). By days six to 10, 41% (95% CI 38 to 43) of cases had resolved in those receiving placebo. We found no data on the cost-effectiveness of antibiotics. No serious outcomes were reported in either the active or placebo arms of these trials, suggesting that important sight-threatening complications are an infrequent occurrence.

AUTHORS' CONCLUSIONS

Although acute bacterial conjunctivitis is frequently self limiting, the findings from this updated systematic review suggest that the use of antibiotic eye drops is associated with modestly improved rates of clinical and microbiological remission in comparison to the use of placebo. Use of antibiotic eye drops should therefore be considered in order to speed the resolution of symptoms and infection.

Preoperative Antisepsis With Povidone-Iodine 5% in Cataract Surgery

PURPOSE

This study aimed to evaluate the efficacy of povidone-iodine (PI) 5% as the only preoperative antiseptic in cataract surgery.

DESIGN

Prospective interventional case series.

METHODS

Fifty patients undergoing phacoemulsification under topical anesthesia in an outpatient surgery setting in a teaching hospital participated in the study. The preoperative antiseptic regimen consisted of instillation into the conjunctival sac and periorbital scrub with PI 5%. No topical antibiotic was given. Eyelid margin swabs were obtained for bacteriological culture before and after PI antisepsis and at the conclusion of surgery. The number of bacterial species isolated was compared with the Wilcoxon test. Anterior chamber aspirates were taken immediately before and after surgery to determine the rate of contamination.

RESULTS

Bacteria were isolated from the eyelid margins of 48 patients (96%; 95% exact confidence interval, 86.3%-99.5%) before surgery, from the eyelid margins of 28 patients (56%) after antisepsis with PI 5%, and from the eyelid margins of 26 patients (56%; 95% exact confidence interval, 41.3%-70.0%) at the conclusion of surgery. The reduction of positive eyelid margin culture was statistically significant (P < 0.0001). Anterior chamber aspirates were positive in 3 patients. One patient with negative growth from anterior chamber aspirates developed culture-negative postoperative endophthalmitis.

CONCLUSIONS

Because 56% of eyelids still have positive culture after PI 5% antisepsis, it might not be relied on as the sole preoperative antiseptic measure. Meticulous surgical technique, together with other modalities of preoperative and intraoperative antisepsis, should be used to prevent postoperative endophthalmitis.

One-day application of topical moxifloxacin 0.5% to select for fluoroquinolone-resistant coagulase-negative Staphylococcus

PURPOSE

To compare selection for fluoroquinolone-resistant bacteria between 1-day and 3-day application of topical moxifloxacin 0.5%.

SETTING

Department of Ophthalmology, Stanford University, Stanford, California, USA.

METHODS

After investigative review board approval, patients scheduled for ocular surgery were randomized to receive topical moxifloxacin 0.5% drops 4 times a day for 1 day or 3 days preoperatively. Conjunctival cultures were obtained at baseline and after antibiotic application. Bacteria were identified and tested for resistance to a battery of antibiotic agents using the Kirby-Bauer disk-diffusion method. The differences in resistance distributions for the most commonly isolated bacteria between baseline (T0) and after antibiotic administration (T1) were compared between the 2 treatment groups.

RESULTS

Coagulase-negative Staphylococcus (CNS) were the most common bacteria isolated at T0 and T1. At T0, the proportion of CNS isolated in the 1-day group (n = 63) that was resistant to fluoroquinolones ranged from 4% to 22% depending on the antibiotic agent tested. After 1-day treatment with moxifloxacin, the percentage of resistant bacteria increased significantly (range 13% to 67%) for all fluoroquinolones except gatifloxacin (P<.05). Resistance to gentamicin and tobramycin also increased significantly. However, patients treated for 3 days (n = 57) showed no differences in bacterial resistance rates to any antibiotic agent tested.

CONCLUSION

Prophylactic topical moxifloxacin 0.5% treatment starting 1 day before ocular surgery resulted in a significant increase in fluoroquinolone-resistant bacteria, while a 3-day antibiotic regimen did not select for resistant organisms.

Prospective randomized comparison of 1-day and 3-day application of topical 0.5% moxifloxacin in eliminating preoperative conjunctival bacteria

PURPOSE

Compare the efficacy of a 1-day versus 3-day application of topical 0.5% moxifloxacin in reducing preoperative conjunctival bacteria.

METHODS

Following IRB approval, patients (n = 144) scheduled for ocular surgery between 2004 and 2005 were recruited and randomized to receive topical 0.5% moxifloxacin drops four times a day for either 1 day (n = 63) or 3 days (n = 57) prior to surgery. Conjunctival cultures were obtained at baseline (T0), after application of antibiotic (T1), following povidone-iodine and additional antibiotic applications immediately before surgery (T2), and after surgery (T3). Cultures were inoculated onto blood and chocolate agar plates and in thioglycolate broth, and then incubated at 37 degrees C for 10 days. Bacterial growth were isolated, identified, quantified, and compared.

RESULTS

There were similar (P = 0.8435) rates of patients with positive thioglycolate cultures between the 1-day (79.37%) and 3-day groups (82.46%) at T0. At T1, T2, and T3, the number of eyes with positive cultures were again similar (1 day, 3 days, P value [T1: 34.9%, 35.1%, P = 0.8631; T2: 14.3%, 7%, P = 0.3245; T3: 7.9%, 3.5%, P = 0.5199]). No significant differences were found between the colony-forming units (CFU) of bacteria on solid agar media in 1-day and 3-day groups at any of the time points studied (P values: 0.1-0.8). Coagulase-negative Staphylococcus was the most commonly isolated (73.3% at baseline).

CONCLUSIONS

In patients undergoing intraocular anterior segment surgery, 1-day and 3-day applications of topical 0.5% moxifloxacin appear to have similar efficacy in reducing perioperative conjunctival bacteria.

A prospective study determining the efficacy of topical 0.5% levofloxacin on bacterial flora of patients with chronic blepharoconjunctivitis

BACKGROUND

To determine the efficacy of conjunctival bacterial eradication following a 1-day, 3-day and 7-day application of topical 0.5% levofloxacin, with and without eyelid scrub, in patients with chronic blepharoconjunctivitis (CBC).

METHODS

Patients with CBC (n = 60) were prospectively randomized to three groups (n = 20 in each group): no antibiotic treatment, topical levofloxacin four times per day in both eyes, and eyelid scrub in addition to topical levovofloxacin four times a day in both eyes. Patients without CBC (n = 40) were enrolled as the negative control group. Cultures of the conjunctiva were obtained from both eyes at baseline, 1 day, 3 days, and 7 days following treatment.

RESULTS

The most common bacteria isolated for all groups at baseline were coagulase-negative Staphylococcus. Eight patients did not complete the study. The remaining 52 patients with CBC had a significantly higher rate of positive thioglycolate broth cultures (94%) compared to a 58% positive culture rate in patient without CBC (P < 0.0001). Treatment with at least 3 days of topical antibiotic in patient with CBC resulted in a significant reduction (P < 0.05) in the number of thioglycolate positive cultures (<or= 60%) compared to non-treated eyes (>or= 88%). Following a minimum of a 1-day application of antibiotic, the median colony-forming unit was 0-1 compared to 3-8 for eyes without antibiotic treatment (P < 0.05). Scrubbing of the eyelids did not provide further benefit compared to antibiotic treatment alone.

CONCLUSIONS

CBC eyes have a significantly higher number of positive cultures than eyes without CBC. The application of topical 0.5% levofloxacin for at least 3 days provided a significant reduction in the number of positive cultures as well as the number of bacteria harbored on the conjunctival surface.