Positive Conjunctival Cultures Research Articles

Preterm infants with positive conjunctival swab culture: risk factors and association with late-onset sepsis-a retrospective cohort study.

Purulent conjunctival discharge in hospitalized preterm infants may indicate conjunctivitis and warrant treatment. The purpose of this study was to examine the relationship between positive conjunctival swab (CS) culture and late-onset sepsis (LOS) in preterm infants. A retrospective cohort study was conducted to determine the relationship between positive CS culture growth results (CSP) obtained in preterm infants ≤34 weeks' gestation and the development of LOS within 120 h of obtaining CS compared with those who had negative CS culture results (CSN). Electronic medical records were reviewed from January 2015 until December 2019 for preterm infants presenting with purulent conjunctival discharge and underwent CS culture testing due to suspected conjunctivitis. Of the 234 CS cultures obtained during the study period, 145 (61.9%) were CSP compared to 89 (38.1%) CSN cultures. Gram-negative organisms accounted for 70% of all CSP cultures, with the remaining 30% being Gram-positive. Patients with CSP were smaller, younger, had lower 1-minute APGAR scores, and required respiratory support more frequently than those with CSN. Infants with CSP received antibiotics for longer periods, both topically and systemically. Infants who developed LOS were more likely to require invasive ventilation (adjusted odds ratio, 33.5; 95% CI, 2.52-446.5, p = 0.008). The incidence of LOS between the two groups was similar, with 6.2% observed in the CSP group compared to 3.4% in the CSN group (p = 0.543). Similarly, the rates of bacteremia were similar in both groups. Of the CSP patients who were presented with bacteremia, four out of seven (57%) exhibited bacteremia caused by the same organism found in their CS cultures. Similarly, within the entire cohort, respiratory cultures were performed on nine intubated patients within two weeks of obtaining CS cultures. Of these, in the CSP group, five out of six (83%) showed an organism identical to that found in the CS cultures. The study found a significant proportion of positive CS cultures in preterm infants, with distinct patient characteristics and treatment compared to negative cultures. While the incidence of LOS was not significantly different between the two groups, some CSP patients demonstrated bacteremia with the same CS organism, suggesting a possible connection between conjunctival or respiratory colonization and bacteremia.

Microbial distributions in the conjunctiva and lacrimal sacs of patients with chronic dacryocystitis in a tertiary hospital.

The aim was to clarify the distributions of bacteria in the conjunctival sac and lacrimal sac in patients with chronic dacryocystitis. In total, 297 (322 eyes) chronic dacryocystitis patients who underwent nasal endoscopic dacryocystorhinostomy (EN-DCR) were included. Conjunctival sac secretions from the affected eye were collected preoperatively, and lacrimal sac retention fluid from the affected side in the same patient was collected intraoperatively. Bacterial culture and drug sensitivity testing were performed to determine bacterial distributions. In total, 127 bacterial isolates (49 species) were detected in 123 eyes in the conjunctival group, with a positivity rate of 38.2% (123/322); 85 bacterial isolates (30 species) were detected in 85 eyes in the lacrimal sac group, with a positivity rate of 26.4% (85/322). The positivity rates were significantly different (P = 0.001) between two groups. The gram-negative bacilli proportion in the lacrimal sac group (36/85, 42.4%) was significantly higher than that in the conjunctival sac group (37/127, 29.2%) ( P = 0.047). Positive conjunctival sac secretion culture (123/322) was significantly associated with increased ocular secretion (281/322, 87.3%) (P = 0.002). Among the culture-positive bacteria in the conjunctival sac group and the lacrimal sac group, 30/127, 23.6% and 43/127, 26.7% and 21/85, 24.7% and 20/85, 23.5% were resistant to levofloxacin and tobramycin, respectively. This study illustrated differences in bacterial distributions between conjunctival sac secretions and retained lacrimal sac fluid in chronic dacryocystitis patients, with a higher proportion of gram-negative bacilli in lacrimal sac secretions. The ocular surface flora in chronic dacryocystitis patients is partially resistant to levofloxacin and tobramycin, which need to be considered by ophthalmologists.

CONJUNCTIVAL SWAB CULTURE IN DIABETIC RETINOPATHY PATIENTS

Background: The normal flora of the eye plays an important role in maintaining ocular homeostasis by various mechanisms. They comprise mainly bacteria which do not cause infection in normal conditions but can be a main source of infection after ocular surgery, trauma or in immunocompromised patients. Immune function is compromised in diabetes mellitus. Patients with diabetes mellitus (DM) are prone to infection because glucose in the skin, urine, mucous membranes and tears promotes growth of microorganism.Aim of the Work: To detect the presence of pathogenic bacteria other than floral bacteria which are important pathogens of ocular infections in diabetic patients.Patients and Methods: This cross-sectional descriptive study was carried out on sixty eyes of sixty patients attending ophthalmology outpatients clinic at Ain Shams University Hospitals. The study was conducted in accordance with the ethical standards stated in the Faculty of Medicine with informed consent obtained.Results: Among 60patients, 26 were males and 34 were females, 35 had NPDR (58%), 25 had PDR (44%), 24 on OHG (40%) ,36 on insulin (60%). Growth of some bacteria was seen in 29 patients (48.3%) out of 60 eyes. The commonest flora isolated was staph coagulase negative (Staph CONg) 31.7%, next was candida 16,7%. Mixed infections had been found in many patients, 57.77% of male subjects had sterile conjunctiva compared to 47.1% in the females. The swab culture of rest of the subjects showed that Staph CONg were the predominant normal flora in both 30.8% and 32.4% in males and females respectively. However, Candida species were found significantly higher in females 23.5%. Positive conjunctival culture was found higher in patients on insulin than OHG, although staph cong, non-hemolytic streptococcus &candida were found higher in patients on insulin therapy but there had no statistical significance, candida was found higher in stage of NPDR than PDR and had statistical significance.Conclusion: Gram-positive bacteria and candida were detected in higher ratios in the conjunctival flora of diabetic patients. Considering that flora elements may be important pathogens in ocular infections, treatment approaches to gram-positive bacterial and fungal infections should not be ignored in cases of ocular infections in diabetics.

The ocular surface bacterial contamination and its management in the prophylaxis of post cataract surgery endophthalmitis.

Objective: To investigate the recent pieces of evidence regarding the bacterial ocular surface contamination and its treatment in the prophylaxis of post-cataract surgery endophthalmitis.Methods: We conducted a literature research on the topic of interest and selected the most relevant data.Results: The studies reported a relatively high rate of positive conjunctival culture and the most frequently isolated organism was Coagulase negative Staphylococcus, which is also the most common etiological agent of the postoperative endophthalmitis. The bacterial ocular surface load is influenced by age, climate, associated diseases, topical and systemic medication. The use of povidone-iodine alone or in association with levofloxacin eyedrops as prophylactic method is effective in reducing the conjunctival bacterial contamination and consequently decreases the incidence of postoperative endophthalmitis.Conclusions: Based on the current pieces of evidence, adequate treatment of the bacterial ocular surface contamination prior to cataract surgery seems to be effective in preventing endophthalmitis after cataract surgery.Abbreviations: EU = European Union, Spp. = Species, HIV = Human Immunodeficiency Virus

Topical proparacaine eye drops to improve the experience of patients undergoing intravitreal injections: A randomized controlled trial.

We sought to evaluate whether additional topical anesthetic, specifically proparacaine 0.5%, improved patient experience with intravitreal injections without hindering antisepsis. A prospective, randomized controlled trial was conducted including 36 eyes of 36 patients undergoing intravitreal injections. Patients were randomized to treatment with additional topical proparacaine 0.5% versus control after undergoing informed consent. All patients prior to intravitreal injection underwent conjunctival culture after one drop of topical proparacaine 0.5% was placed. Half of patients then received an additional drop of proparacaine and then underwent a second conjunctival culture. The other half of patients had a drop of povidone iodine and then a second conjunctival culture. Intravitreal injection followed conjunctival cultures. To evaluate their experience, patients were provided with a survey. In total, 36 patients were enrolled in the study. Three of 36 (8.3%) patients had positive conjunctival cultures after proparacaine eye drops alone. One of 17 (5.8%) patients had a positive conjunctival culture after a second drop of proparacaine. One of 19 (5.3%) patients had a positive culture after proparacaine and povidone iodine. By noninferiority analysis, proparacaine was inferior to povidone iodine (p = .28). Patient experience surveys did not differ between groups. Patient perception did not significantly differ whether or not additional proparacaine drops were used prior to intravitreal injection in a randomized controlled trial. While proparacaine has some antiseptic properties, these were found to be inferior to those of povidone iodine. Therefore, while povidone iodine is essential for antisepsis, additional proparacaine drops should not interfere with antisepsis.

The effect of recurrent povidone-iodine usage on conjunctival flora in diabetic patients undergoing intravitreal injections.

The purpose was to evaluate the change in the microbiological profile of diabetic patients undergoing intravitreal injections for diabetic macular edema. Patients were included in this prospective study when referred for the first time for intravitreal injection to treat diabetic macular edema. For each patient, conjunctival cultures were taken from the lower fornix of each eye prior to the povidone-iodine application and the intravitreal injection. An additional culture was taken from the treated eye 20 min after the injection. The same culture protocol was used for the two following injections of these patients. A later conjunctival culture was also taken a month after the last injection. Twenty-one eyes of 21 patients were included. The mean duration of diabetes was 13.7 ± 7.9 years. Prior to the first intravitreal injection, 33% of cultures were positive. Prior to the third intravitreal injection, 26% of cultures were positive (p = 0.63), and 1 month after the last injection, 18% of cultures were positive (p = 0.495). The mean HbA1C was 8.1% ± 1.7%. HbA1C of patients with positive cultures was 8.0% ± 1.1% at the first intravitreal injection and 8.2% ± 1.0% at the third intravitreal injection. This was compared with HBA1C in eyes with negative cultures: 7.4% ± 1.2% (p = 0.45) and 7.1% ± 1.0% (p = 0.14), respectively. Repeated intravitreal injection for diabetic macular edema with application of povidone-iodine 5% in diabetic patients did not lead to a significant change in the percentage of positive conjunctival cultures. Patients with higher HbA1C had a slight, non-statistically significant trend for positive cultures.

Ocular Surface Microbial Flora in Patients with Chronic Limbal Stem Cell Deficiency Undergoing Cultivated Oral Mucosal Epithelial Transplantation.

PURPOSE:The purpose of this study is to analyze the ocular surface microbial flora in patients with chronic limbal stem cell deficiency (LSCD) due to Stevens–Johnson Syndrome (SJS) and ocular chemical injury undergoing cultivated oral mucosal epithelial transplantation (COMET).METHODS:Patients of SJS and chemical injury who had bilateral total LSCD planned for COMET were studied. Conjunctival swab was taken before surgery. Parameters evaluated were organism cultured, sensitivity pattern, frequency of positive culture, and clinical impact on management strategy.RESULTS:Thirteen patients were included in which nine were males and four females. All patients had positive conjunctival swab culture. Most common organism isolated was Staphylococcus epidermidis, followed by Staphylococcus aureus and Pseudomonas aeruginosa. The staphylococcal species isolated were sensitive to all the conventional antibiotics while Pseudomonas cultured showed resistance to cefuroxime, ceftriaxone, and ceftazidime. Repeat conjunctival swab sent after a week of topical antibiotic therapy yielded positive culture of the same organism twice in 25% (3/12), thrice in 58.3% (7/12), and four times in 16.6% (2/12) of the patients. One patient had a polymicrobial flora with positive yield of S. aureus (thrice), S. epidermidis (twice), and P. aeruginosa (twice) in consecutive conjunctival swab culture in the absence of clinical infection. Two patients with persistent positive cultures had to undergo repeat oral mucosal harvesting as the transplantation of the cultivated explants had to be deferred.CONCLUSION:Ocular surface in LSCD patients yielded pathogenic organisms on culture. Poor ocular surface with absent tear film could be the contributing factors. It is important to perform the conjunctival swab culture before COMET surgery.

The Effect of Topical Ocular Anesthetic Proparacaine on Conjunctival and Nasal Mucosal Flora in Dry Eye Disease Patients.

The aim of this study was to investigate the effect of topically applied ocular anesthetic proparacaine on conjunctival and nasal bacterial mucosal flora in patients with dry eye disease. A Schirmer test was done with (group 1) and without (group 2) topical anesthetic proparacaine to 40 patients in each group. Conjunctival and nasal cultures were obtained before and 10 min after performing the Schirmer test. The bacterial culture results and the isolated bacteria were recorded in two groups. Patients’ mean age was 62 years (70 female, 10 male). Before the application of topical anesthetic, 50 (62.5%) and 62 (77.5%) had positive conjunctival and nasal culture, respectively, with the most commonly isolated organism being coagulase-negative Staphylococcus in each group. In group 1 the conjunctival bacterial culture positivity rate decreased from 26 (65%) to six (15%) eyes (p < 0.001); however, this rate decreased slightly from 24 (60%) to 20 (50%) eyes in group 2 (p > 0.05). For the nasal cultures, the bacterial culture positivity rate decreased from 80% to 20% and from 75% to 65% in groups 1 (p < 0.001) and 2 (p > 0.05), respectively. Topical ocular anesthetic proparacaine has antibacterial activity in both conjunctival and nasal flora in patients with dry eye disease.

Evaluation of Microbial Flora in Eyes With a Boston Type 1 Keratoprosthesis

To evaluate the microbial flora of eyes with a Boston Keratoprosthesis (K-Pro). A prospective study was performed for 17 eyes of 15 patients who underwent a K-Pro implantation between September 2005 and June 2011. Preoperative diagnoses included failed corneal grafts, limbal stem cell deficiency, chemical burns, and Stevens-Johnson Syndrome. The patients used topical antibiotics after their surgery including a fluoroquinolone, polymyxin-trimethoprim, vancomycin, or a combination of the 3. The conjunctiva in the study eye was swabbed and cultured. A separate culture was taken of the contralateral eye as well. If available, the bandage contact lens was removed, and half of it was placed in thioglycolate broth, and half in 5 mL of a sterile balanced salt solution. The contact lens in the balanced salt solution was sonicated using a QSonica Q125 sonicator (Newtown, CT) for 1 minute, at an amplitude of 20%. Ten microliters of fluid was subsequently cultured. Of the patients who underwent the K-Pro surgery during that time period, 15 patients with 17 eyes were able to participate in the data collection. Nine of the 17 eyes implanted with the K-Pro (53%) had positive cultures. Two of the 13 (15%) of the control swabs exhibited bacterial growth. Eight percent (1/12) of the sonicated lenses were positive on culture, whereas 4/12 (33%) of the lenses placed in thioglycolate broth were positive for organisms. Despite being on antibiotics, eyes implanted with the K-Pro were more likely to have a positive conjunctival culture in our cohort as compared with that of fellow eyes.

Study of aerobic bacterial conjunctival flora in patients with diabetes mellitus

Normal bacterial flora may be altered by a variety of factors. To study the aerobic bacterial conjunctival flora in patients with diabetes mellitus and to find its clinical significance by comparing the results to the conjunctival flora of non-diabetic subjects. A total of 75 diabetic patients were included as cases and 25 nondiabetics as controls to compare the results. Specimens for the study of conjunctival flora were taken by rubbing sterile cotton-tipped swabs to the inferior palbebral conjunctiva. The conjunctival culture report of the patients with diabetic mellitus was compared to that of nondiabetic subjects. Positive conjunctival cultures were seen in a higher percentage of patients with diabetes (unilateral and bilateral positive conjunctival cultures 34.66 % and 58.66 % respectively) compared to that in non-diabetic controls (unilateral and bilateral positive conjunctival cultures 24 % and 16 % respectively). Diabetics showed a higher proportion of coagulase negative staphylococci (45.33 %), compared to the non-diabetic group (16 %). Among the diabetic patients, positive conjunctival cultures were detected more frequently in those with diabetic retinopathy compared to those without retinopathy. A higher proportions of bilateral positive conjunctival cultures were seen in cases with proliferative diabetic retinopathy (38.63 %) in comparison to patients with no retinopathy and different stages of non-proliferative diabetic retinopathy. The conjunctival floral pattern with increased bacteria in diabetics is a predominant cause of many diabetes-related ocular infections. The presence of diabetic retinopathy is an indicator for increased colonization of conjunctiva, and its severity correlates with the severity of diabetic retinopathy.

Pasteurella canis and Granulicatella adiacens Conjunctivitis Outbreak Resistant to Empirical Treatment in a Child Welfare Agency

To investigate pathogens associated with bacterial conjunctivitis resistant to the empirical treatment and their antibiotic resistance in a child welfare agency. Twenty-eight eyes in 14 children with a median age of 3 months with conjunctivitis resistant to the empirical treatment were included in this study. Samples were taken three times from the inferior fornix in both eyes using cotton swabs, cultured onto chocolate and blood agar, and prepared for Gram staining. Antibiograms were evaluated according to the Clinical and Laboratory Standards Institute criteria by disc diffusion method. The conjunctival culture positivity rate was 35.7% in eyes with conjunctivitis resistant to the empirical treatment. The most common isolated bacteria were Pasteurella canis (25%), penicillin-nonsusceptible Streptococcus pneumoniae (7.1%), and Granulicatella adiacens (3.6%). According to culture results, ophthalmic solutions of vancomycin (50 mg/mL) or gentamicin (30 mg/mL) were applied in eyes with positive conjunctival culture. Previously applied multiple treatments were stopped in eyes with negative conjunctival culture. All eyes improved clinically during follow-up. Because unusual pathogens may cause a conjunctivitis outbreak, physicians should not insist on empirical treatment. Taking conjunctival culture and antibiotic switching according to antibiogram may be helpful.

The effect of Ophthalmic Patch on Conjunctiva of Neonates under Phototherapy

Objective Conjunctivitis is a common disease in neonates. Several bacterial and viral infectious agents may cause it. Tear circulation and blinking has protective effects from bacterial colonization in the conjuntival sac. Reduced blinking increases the possibility of bacterial conjunctivitis. We studied the effect of eye patches on bacterial colonization of the conjunctival sac. Methods In 100 icteric neonates who needed phototherapy and occlusive patches for their eyes during the procedure we did conjunctival bacterial culture before and after 48 hrs after occlusive patches. The results of two cultures were analyzed with statistical tests, McNemar, chi- square and, binominal with SPSS V18 software. Results In 100 neonates there were 51 (51%) males 49 (49%) females. The mean birth weight was 2578±736 g. Culture before ophthalmic patches showed 20 (20%) cases with positive conjunctival cultures and 76 cases (76%) with positive culture 48 hrs after use of eye patches. Conclusion Eye patches during phototherapy increase bacterial colonization in the conjunctival sac. We must be aware of this complication during phototherapy.

Preoperative topical moxifloxacin 0.5% and povidone–iodine 5.0% versus povidone–iodine 5.0% alone to reduce bacterial colonization in the conjunctival sac

To assess the effectiveness of adding topical moxifloxacin 0.5% to topical povidone-iodine 5.0% for preoperative reduction of bacterial recovery from the conjunctiva. Emek Medical Center, Afula, Israel. The study population comprised adult patients scheduled for elective intraocular surgery. Two hours before surgery, patients were randomly assigned to topical therapy with moxifloxacin 0.5% drops (study group) or normal saline drops (control group). Povidone-iodine 5% solution was also instilled in the conjunctival sac in both groups for 3 minutes immediately before surgery. Conjunctival cultures were obtained before prophylactic therapy and just before surgery. The major outcome measures were the rate of bacterial colonization and bacterial type in conjunctival cultures obtained after instillation of povidone-iodine and immediately before surgery. Overall, 464 patients completed the study; there were 237 patients in the study group and 227 patients in the control group. Positive conjunctival cultures were obtained before prophylactic therapy in 91 patients (38%) in the study group and 94 patients (41%) in the control group and just before surgery in 10 patients (4%) and 6 patients (3%), respectively; neither difference was statistically significant. Coagulase-negative Staphylococcus was the most prevalent bacteria and was found equally in both groups. Treatment with povidone-iodine 5.0% alone was effective in preoperative reduction of conjunctival bacterial colonization. Adding topical moxifloxacin 0.5% to povidone-iodine 5.0% had no significant effect on further reduction in the bacterial colonization rate.

Prospective Study of Risk Factors for Conjunctival Bacterial Contamination in Patients Undergoing Intraocular Surgery

To determine whether a patient's age, gender, local or systemic risk factors affect the rate of preoperative bacterial contamination. Consecutive 1,474 patients undergoing intraocular surgery were enrolled in this prospective masked study. Past medical history was noted and examinations were performed. The patients were divided into four groups: a control group (without local or systemic risk factors), those with local risk factors (chronic use of topical medications, contact lens wear, blepharitis, chronic eyelid or conjunctival inflammation), those with systemic risk factors (immunosuppression, diabetes, autoimmune conditions, and asthma), and those with both. Conjunctival cultures were obtained before surgery. Among the 1,474 patients, 914 bacteria were isolated from 214 (14.9%) patients. Advanced age was associated with a higher rate of positive conjunctival cultures (p<0.005). No statistical difference was found with regard to gender (p=0.7173). Among the 282 patients in the control group, 14 (5%) had a positive conjunctival culture. Compared to the control group, positive conjunctival cultures were found in 118 out of 503 patients (23.5%) with local risk factors (p<0.0001), 65 out of 545 patients (11.9%) with systemic risk factors (p=0.0019), and 22 out of 144 (15.3%) with both (p=0.0006). Two patients developed postoperative endophthalmitis (0.14%), one with both local risk and systemic factors and the other with a systemic risk factor. Patients with local or systemic risk factors or advanced age were found to have a higher rate of bacterial conjunctival contamination before intraocular surgery.

Effect of Chronic Topical Glaucoma Medications on Aerobic Conjunctival Bacterial Flora

To investigate whether the chronic topical medications affect aerobic conjunctival bacterial flora of patients with glaucoma and to compare their findings with the findings of the controls. Eighty-one patients and 67 healthy control subjects participated in this case-control study. Duplicate conjunctival swab specimens were collected from each patient at the microbiology laboratory and were investigated for the presence of aerobic bacteria. All bacterial species from isolated colonies were identified. Thirty seven (45.7%) of the 81 patients and 25 (37.3%) of 67 controls had positive conjunctival cultures. Coagulase-negative Staphylococcus was the most commonly isolated bacterial species in both groups. There were no statistically significant differences between the prevalence of other conjunctival cultures testing positive for any of the isolated organisms. The patients were also evaluated with respect to the presence of a systemic illness. Age, sex, presence of diabetes and asthma, duration of antiglaucomatous medication, and number of medications used did not have an effect on culture positivity in both groups when evaluated by logistic regression model. The conjunctival culture positivity was higher in patients with glaucoma than in the healthy controls and in patients with diabetes than in patients without diabetes, although both were statistically insignificant. Aerobic conjunctival flora of the patients using topical glaucoma medications and the controls did not differ. Further studies are needed to comment on the clinical importance of these findings.

Conjunctival Flora in Patients with Parkinson's Disease

Purpose: To identify the conjunctival flora in patients with Parkinson's disease (PD) and compare it with the conjunctival flora of healthy subjects. Methods: One hundred six eyes of 106 patients with PD and 102 eyes of 102 age-matched healthy subjects were included in the study. All subjects had a detailed anterior segment examination, including eye blink rate and conjunctival cultures. Conjunctival cultures were taken with a sterile cotton-tipped dry swab without topical anesthesia. The culture samples were inoculated onto 5% sheep blood agar and chocolate agar, as well as brain heart infusion broth. The bacterial growth was evaluated in a quantitative manner as colony-forming units (CFU). All bacterial isolates were identified, and statistical analyses were performed by chi-square test to determine if there were differences in flora between PD and control groups. Results: Eighty-six (81.1%) of the 106 eyes in patients with PD and 73 (71.5%) of the 102 eyes in control group were found to have positive conjunctival cultures (p = 0.144). Coagulase-negative Staphylococcus was the most commonly isolated bacterial species in both groups, found in 45 (42.4%) and 49 (48%) of eyes in patients with PD and control group, respectively (p = 0.503). Among all bacterial isolates, only Staphylococcus aureus was found to be statistically different between the two groups, noted in 32 (30.1%) and 10 (9.8%) of eyes in patients with PD and control group, respectively (p = 0.001). Conclusions: Coagulase-negative Staphylococcus, Staphylococcus aureus, and Corynebacterium species were the most commonly isolated bacterial species in the PD group. Among all bacterial isolates, only Staphylococcus aureus was significantly higher in the conjunctival flora of patients with PD than in those in the control group.

Comparative study of gentamycin and povidone-iodine on eliminating the conjunctival bacteria

To study the efficacy of gentamycin, 0.5% povidone-iodine and 5.0% povidone-iodine in eliminating rate of positive conjunctival bacteria cultures and aqueous humor contamination, and to observe their adverse effects. It was a comparative study. Three hundred patients (300 eyes) were randomized to three groups: gentamycin group, 0.5% povidone-iodine group and 5.0% povidone-iodine group. All patients received 1-day (6 times) topical application of 0.3% ofloxacin before surgery. Approximately 5 minutes before surgery, the conjunctival sac was irrigated with 5 - 8 ml gentamycin, 0.5% povidone-iodine or 5.0% povidone-iodine, correspondingly. Conjunctival cultures were obtained at the following time points: before receiving any topical medications; after application of 1-day topical 0.3% ofloxacin, before irrigating the conjunctival sac; immediately before surgery approximately 5 minutes after conjunctival sac irrigation and at the end of the surgery. Anterior chamber aspirates were obtained at the beginning of the surgery. Bacteria isolated were identified and antibiotic susceptibility was determined. The rate of positive conjunctival cultures among each group was compared and significance of the difference was tested with the Pearson chi-square test. Rate of positive conjunctival cultures before the conjunctival irrigation was 79.7%, 76.6% and 77.8% in the gentamycin group, 0.5% povidone-iodine group and 5.0% povidone-iodine group, respectively. The difference between these three groups was not statistically significant (chi2 = 0.28, P = 0.86). At the end of surgery, the rate of positive conjunctival cultures in these three groups was 11.7%, 8.3% and 6.3%, respectively. The difference between these three groups was also not statistically significant (chi2 = 1.74, P = 0.41). The average rate of anterior aqueous contamination was 4.9% and there was no significant difference among these three groups (P > 0.05). Both 0.5% povidone-iodine and 5.0% povidone-iodine using for irrigating conjunctival sac are safe. Gentamycin, 0.5% povidone-iodine and 5.0% povidone-iodine have similar effects on the reduction of the bacteria in conjunctival sac.

Prospective Comparison of Topical Moxifloxacin in Eliminating Conjunctival Bacterial Flora Following a One-Day or One-Hour Application

The aim of this study was to compare the efficacy of a 1-hour(h) versus 1-day application of topical moxifloxacin in eliminating conjunctival bacterial flora. In this prospective, nonrandomized, controlled trial, the surgical eyes of 60 patients scheduled for intraocular surgery received topical moxifloxacin four times a day, starting 1 day prior to surgery and three additional applications at 5-minute intervals 1 h before surgery. The nonsurgical eye of each patient only received three applications of the same antibiotic at 5-minute intervals 1 h before surgery. Conjunctival cultures were obtained at baseline and after antibiotic application. Prior to antibiotic application, 80% of surgical eyes and 70% of nonsurgical eyes had positive cultures. Following the 1-day application, significantly fewer eyes (40%) had positive cultures (P < 0.0001), with a further reduction to 32% with three additional doses 1 h prior to surgery. In the nonsurgical eye, the decrease in the percentage of positive cultures, from 55% to 53% following the three applications 1 h prior to surgery, was not significant (P > 0.9999). The 1-day application was associated with significantly fewer positive cultures, compared to the 1-h group (P = 0.0267). The one-day application of moxifloxacin resulted in significantly fewer positive conjunctival cultures, compared with a 1-h application.

Flora bacteriana conjuntival após uso tópico de ciprofloxacino e gatifloxacino em cirurgia de catarata

To evaluate alterations of the conjunctival flora after the use of 0.3% ciprofloxacin and gatifloxacin in the prophylaxis of patients undergoing cataract surgery. 40 patients undergoing cataract surgery were distributed into two groups according to the use of antibiotic eye drops: Group A: 0.3% ciprofloxacin and Group B: 0.3% gatifloxacin. Both groups used antibiotic eye drops 1 hour before surgery and 14 days after surgery. Conjunctival material was collected at 5 time points: 1 hour before surgery, without any topical medication (t0); immediately before the application of povidone-iodine (PVPI) (t1), before the beginning of surgery, after povidone-iodine (t2), 14 days (t3) and 28 days after surgery (t4). Preoperative antibiotics reduced the positivity of the cultures before the use of PVPI in both groups, although in Group A this reduction was not significant (Group A - p=0.07 and Group B - p=0.04). The number of positive cultures was reduced in all groups after the use of povidone-iodine and on the 14th postoperative day (p<0.05). In t4 there was a reduction in the frequency of coagulase-negative Staphylococcus in Group A compared with Group B (p<0.05); the susceptibility to ciprofloxacin was also reduced in all groups, when compared with t0. Gatifloxacin eye drops applied one hour before surgery significantly reduced the number of positive conjunctival cultures. Both antibiotics reduced the conjunctival flora when administered in the postoperative period.

Prospective Randomized Comparison of 1-Day versus 3-Day Application of Topical Levofloxacin in Eliminating Conjunctival Flora

To compare efficacy of a 1-day versus 3-day application of topical levofloxacin in reducing ocular surface bacteria. In this prospective randomized controlled trial, 100 volunteer patients (50 per group) were assigned to receive topical 0.5% levofloxacin four times daily for 1 day or 3 days. Conjunctival cultures were obtained prior to (T0) and after the application of antibiotics (T1). Additionally, all patients received topical levofloxacin at 5-minute intervals for three applications (T2), followed by two drops of topical 5% povidone-iodine (T3). Conjunctival cultures were obtained at timepoints T2 and T3. A 1-day application of topical levofloxacin significantly reduced (p = 0.0004) the number of eyes with positive conjunctival cultures from 41 eyes (82%) to 23 eyes (46%). Similarly, a 3-day application significantly reduced (p = 0.0001) the positive culture rate from 37 eyes (74%) to 17 eyes (34%). Two drops of povidone-iodine further reduced the positive culture rate for both groups to 20% (10 eyes for each group). There was no significant difference in positive culture rate between the 1-day and 3-day groups at T0 (p = 0.4689), T1 (p = 0.3074), T2 (p = 0.6706), or T3 (p = 1.000). The application of topical 0.5% levofloxacin for 1 or 3 days significantly reduced the number of eyes with positive conjunctival cultures. The addition of 5% povidone-iodine further eliminated bacteria from the conjunctiva. The application of levofloxacin for 1 day appears to be as effective as a 3-day application.