The efficacy of intravitreal piperacillin/tazobactam in rabbits with experimental Staphylococcus epidermidis endophthalmitis: a comparison with vancomycin

BACKGROUND: To investigate the efficacy of intravitreal piperacillin/tazobactam in rabbit eyes with experimental S. epidermidis endophthalmitis and to compare the outcomes with intravitreal vancomycin application. MATERIAL AND METHODS: Twenty-four New Zealand white albino rabbits were divided into three equal groups (n=8 in each), and the right eyes received 0.1-ml intravitreal injections of S. epidermidis suspension. The left eyes served as uninfected controls and were injected with 0.1 ml of saline solution. The right eyes of rabbits in group 1 were treated with intravitreal injection of 250 microg/0.1 ml piperacillin/tazobactam 24 h after intravitreal inoculation of S. epidermidis whereas group 2 eyes received intravitreal 1 mg/0.1 ml vancomycin. Group 3 eyes received no treatment and served as infected controls. Clinical examination of the eyes in each group was performed on the 1st, 3rd and 6th day after the inoculation of S. epidermidis. On the 6th day, 0.1-ml vitreous aspirates were obtained for microbiological analysis, and then the eyes were enucleated for histopathological evaluation. RESULTS: There were no statistically significant differences in mean clinical scores between the groups on the first day after S. epidermidis inoculation (p>0.05). On the 6th day, the mean clinical score of group 3 was significantly higher (p<0.001), but the mean clinical scores of groups 1 and 2 were similar (p=0.812). The mean logarithmic value of colony-forming units per milliliter of groups 1, 2 and 3 were 0.6+/-1.3, 0.5+/-1.5 and 5.3+/-0.7, respectively. Mean histopathological scores of the groups were 8.3+/-0.9, 7.5+/-1.3 and 15.6+/-1.2, respectively. Group 3 eyes had significantly more colony-forming units per milliliter and a higher histopathological score (for each, p<0.001), and there were no statistically significant differences in microbiological and histopathological scores between groups 1 and 2 (for each, p>0.05). CONCLUSION: Intravitreal application of 250 microg/0.1 ml piperacillin/tazobactam seems to be approximately equally effective with intravitreal 1 mg/0.1 vancomycin application in the treatment of experimental S. epidermidis endophthalmitis. Therefore, intravitreal piperacillin/tazobactam may be an alternative therapeutic option in the treatment of S. epidermidis endophthalmitis.     

High dose intramuscular methylprednisolone in experimental Staphylococcus aureus endophthalmitis.

We attempted to determine whether treatment using intramuscular methylprednisolone plus intravitreal vancomycin decreased ocular inflammation and preserved retinal function better in experimental Staphylococcus aureus (S. aureus) endophthalmitis than treatment with intravitreal vancomycin alone. Sixteen rabbits received intravitreal inoculations in both eyes with S. aureus and the rabbits were divided into two groups (group I and group II) of eight rabbits each. Group I rabbits were treated with one injection of intravitreal vancomycin in each eye at either 24, 36, 48 or 72 hours after bacterial inoculation followed by seven consecutive days of high dose intramuscular methylprednisolone (30 mg/kg per day). Group II rabbits were treated with only one intravitreal injection of vancomycin in each eye at equivalent time intervals as in Group I. Clinical evaluations of ocular inflammation were performed by slit-lamp biomicroscopy and indirect ophthalmoscopy. Electroretinography (ERG) was performed eight days after bacterial inoculation to assess retinal function in all eyes. The combination of intramuscular methylprednisolone and intravitreal vancomycin resulted in a degree of ocular inflammation equal to eyes treated with intravitreal vancomycin alone at all treatment intervals. ERG responses were not significantly different in either group. A single intravitreal injection of vancomycin plus daily intramuscular methylprednisolone for seven days were found neither to decrease ocular inflammation nor preserve retinal function better than a single intravitreal injection of vancomycin in our experimental model of S. aureus endophthalmitis.     

Effects of intravitreal corticosteroid in the treatment of Staphylococcus aureus-induced experimental endophthalmitis

PURPOSE: To investigate whether intravitreal injection of dexamethasone in addition to antibiotics can minimize intraocular tissue injury caused by Staphylococcus aureus endophthalmitis. METHODS: Albino rabbits were infected with an intravitreal injection of 1000 colony-forming units of S. aureus. The rabbits were randomized to receive no treatment (control group; n = 2), intravitreal vancomycin and amikacin (n = 5), or a combination of intravitreal vancomycin, amikacin, and dexamethasone (n = 5) 20 hours following inoculation of bacteria. All rabbits except for the control group also received intravenous imipenem every 8 hours for 4 days. The eyes were evaluated by clinical examination, electroretinogram (ERG), and histologic studies. RESULTS: Eyes treated with intravitreal dexamethasone demonstrated less inflammation on clinical examination compared with eyes that received antibiotics alone. The ERG responses of eyes that received both intravitreal antibiotics and steroid were significantly better at 45 hours, 7 and 14 days following inoculation (P < 0.05) compared to eyes that received antibiotics alone. Histologic studies 14 days following infection demonstrated less tissue destruction for eyes treated with dexamethasone. CONCLUSION: Compared to intravitreal antibiotics alone, intravitreal corticosteroids may improve visual outcome of S. aureus endophthalmitis by reducing inflammation and preserving electrophysiologic retinal function.     

Intravitreal trovafloxacin against experimental Staphylococcus epidermidis endophthalmitis

This study was designed to test the effects of intravitreal trovafloxacin on an experimental rabbit model of Staphylococcus epidermidis endophthalmitis. Out of 26 rabbits, 22 were given intravitreal S. epidermidis (100,000 CFU). At 24 h, group 1 (8 rabbits) and, at 48 h, group 2 (8 rabbits) received 100 microg intravitreal trovafloxacin. Group 3 (6 rabbits) was used as inoculated but untreated controls. Four rabbits (group 4) were used as uninfected controls. Clinical scores were calculated at 24, 48 and 72 h. Microbiological and histopathological scorings were made. Microbiological analysis showed that trovafloxacin administered at 24 or 48 h significantly reduced the number of bacteria compared to the untreated group. We conclude that trovafloxacin applied at 24 or 48 h is effective against S. epidermidis endophthalmitis in this experimental rabbit model.     

A comparison of intravitreal piperacillin/tazobactam with ceftazidime in experimental Pseudomonas aeruginosa endophthalmitis

In the present study, we aimed at comparing the efficacies of intravitreal piperacillin/tazobactam and ceftazidime applications in the treatment of experimental Pseudomonasaeruginosa endophthalmitis in rabbit eyes. Twenty-four New Zealand white albino rabbits were divided into three groups (n=8 in each), and the right eyes received 0.1 ml intravitreal injections of P. aeruginosa suspension. The left eyes served as uninfected control and were injected with 0.1 ml of saline solution. The right eyes of rabbits in group 1 were treated with intravitreal injection of 250 microg/0.1 ml piperacillin/tazobactam 24 hr after intravitreal inoculation of P. aeruginosa, whereas group 2 eyes received intravitreal 1 mg/0.1 ml ceftazidime. Group 3 eyes received no treatment and served as infected controls. Clinical, microbiological and histopathological evaluations of the eyes in each group were performed on the 1st, 3rd, and 6th day after the inoculation of P. aeruginosa. The mean clinical scores of each group were similar at the first day after P. aeruginosa inoculation (P>0.05). At the 6th day, there was no statistically significant difference in mean clinical scores between group 1 and 2, but mean clinical score of group 3 was significantly higher (P<0.001). Microbiological analysis and histopathological scoring demonstrated no statistically significant difference between group 1 and 2 (for each, P>0.05). Group 3 eyes had a significantly more CFU/ml and higher histopathological score (for each, P<0.001). In conclusion, intravitreal application of 250 microg/0.1 ml piperacillin/tazobactam seems to be effective in the treatment of P. aeruginosa endophthalmitis in rabbits, but is not superior to intravitreal ceftazidime application. Therefore, intravitreal piperacillin/tazobactam may be a useful alternative to ceftazidime for pseudomonal endophthalmitis.     

The efficacy of piperacillin/tazobactam in experimental Pseudomonas aeruginosa endophthalmitis: a histopathological and microbiological evaluation

PURPOSE: To investigate the efficacy of intravitreal piperacillin/tazobactam (250 microg/0.1 ml) in the treatment of experimental Pseudomonas aeruginosa endophthalmitis in rabbits. MATERIALS AND METHODS: Twenty New Zealand White albino rabbits were used in this study. The rabbits were divided into two groups (10 rabbits in each), and the right eyes were treated with 0.1 ml intravitreal injections of P. aeruginosa suspension (ATCC 27853, 2 x 10(4) CFU); the left eyes served as uninfected control and were injected with 0.1 ml of saline solution. The right eyes of rabbits in group 1 (n = 10) received intravitreal injection of 250 microg piperacillin/tazobactam 24 h after intravitreal inoculation of P. aeruginosa. Group 2 eyes (n = 10) received no treatment and served as infected controls. Clinical examination of the eyes in each group was performed on the first, third, and sixth day after the inoculation of P. aeruginosa. After the last ophthalmic examination, 0.1 ml vitreous aspirates were obtained for microbiological analysis, and then the eyes were enucleated for histopathological evaluation. RESULTS: The mean clinical scores of group 1 and group 2 at the first day after P. aeruginosa inoculation were similar (p > 0.05). At the sixth day, the mean clinical score of group 1 was significantly lower when compared with group 2 eyes (p < 0.001). Microbiological analysis revealed that group 2 had a significantly more cfu/ml than group 1 (p < 0.001), and the mean histopathological score of group 2 was significantly higher than group 2 (p = 0.009). CONCLUSIONS: Intravitreal application of 250 microg/0.1 ml piperacillin/tazobactam seems to be effective in the treatment of P. aeruginosa endophthalmitis in rabbits. Intravitreal piperacillin/tazobactam combination may be a new therapy for P. aeruginosa endophthalmitis.     

The efficacy of intravitreal levofloxacin and intravitreal dexamethasone in experimental Staphylococcus epidermidis endophthalmitis

This study was designed to investigate the efficacy of intravitreal levofloxacin, and intravitreal levofloxacin and dexamethasone combined in Staphylococcus epidermidis endophthalmitis. Albino rabbits (n = 25), infected with an intravitreal inoculum of S. epidermidis (1.0 x 10(5) colony forming units/0.1 ml), were divided into five groups (n = 5). Groups 1 and 2 received treatment 24 h after the inoculation, and groups 3 and 4 48 h after the inoculation. No treatment was given to the control group. Treatment efficacy was assessed by vitreous culture, clinical examination and histopathology. Five days after treatment, groups 1 and 2 had significantly lower clinical scores than the control group (p = 0.004, p = 0.007). The culture results of the treatment groups were sterile. The histopathological scores of the treatment groups were lower than the control group (p = 0.007). Studies on retinal toxicity and dose-response relation are needed to prove the efficacy of levofloxacin in S. epidermidis endophthalmitis.     

Effectiveness of topical taurolidine versus ciprofloxacin, ofloxacin, and fortified cefazolin in a rabbit Staphylococcus aureus keratitis model

PURPOSE: Taurolidine is a broad-spectrum, non antibiotic antimicrobial agent, not previously tested against the common causes of bacterial keratitis. This study, employing an experimental rabbit model of Staphylococcus aureus keratitis, investigated the effectiveness of topical taurolidine in reducing the number of bacteria, and its effectiveness was compared with topical ciprofloxacin, ofloxacin, and 5% cefazolin. METHODS: The right corneas of all rabbits were intrastromally injected with 100 colony-forming units of Staphylococcus aureus ATCC strain 25923. The animals were divided into the following seven groups: Group 1 (6 rabbits) received taurolidine, group 2 (6 rabbits) received ciprofloxacin, group 3 (6 rabbits) received ofloxacin, group 4 (6 rabbits)received cefazolin, group 5 (5 rabbits) received polyvinylpyrrolidone (vehicle),group 6 (4 rabbits) received sterile water, and group 7 (4 rabbits) was left un-treated (control group). The eyes were topically treated every 30 min with the above-mentioned substances from 4 to 9 h postinjection. One hour after the last drop administration (at 10 h postinjection), signs of inflammation were scored in a masked fashion by slit-lamp examination. Then, their corneas were processed. The number of colony-forming units (cfu) per cornea in all eyes was also determined. RESULTS: All antimicrobial (taurolidine, ciprofloxacin, ofloxacin, and cefazolin) treatments significantly reduced cfu numbers and slit-lamp examination scores compared with untreated eyes, eyes that received the vehicle, or eyes with sterile water (all p values <0.05). Regarding cfu numbers, although taurolidine therapy was significantly less effective than ciprofloxacin or ofloxacin,there was no significant difference between taurolidine and cefazolin groups.However, taurolidine had similar clinical examination scores with the other antimicrobials, while it had lower scores than the vehicle, sterile water, or un-treated eyes. CONCLUSIONS: The results obtained in this study suggest that topicaltaurolidine is an effective, novel ocular chemotherapeutic agent for the therapy of rabbit experimental Staphylococcus aureus keratitis. This drug may be a useful and promising ocular antimicrobial.     

Effect of taurolidine on the normal eyelid and conjunctival flora

PURPOSE: The effectiveness of the topical taurolidine was evaluated in eradicating or reducing microorganisms in the normal flora of human eyes in a randomized controlled study and analyzed also the irritating effects of taurolidine on the ocular surface. METHODS: One hundred and twenty eyes of 110 patients awaiting cataract surgery were randomly divided into four groups consisting of 30 eyes each. The first group received 0.05% taurolidine, the second received 0.3% gentamicin, the third received vehicle eyedrops and the fourth received saline to the preoperative eye four times daily for two days. Cultures were obtained from the eyelids and conjunctivas of all subjects prior to the therapy and again at the end of 48 hours. Micro-biological identification and colony counts were performed by standard laboratory methods, and the results were compared. The patients were clinically evaluated for symptoms and signs at the end of therapies. RESULTS: Taurolidine and gentamicin produced a significant decrease from the basal bacteriological state: the number of colonies (p < 0.01 for taurolidine, p < 0.01 for gentamicin) was reduced by both agents. Staphylococcus epidermidis was the most common microorganism isolated before therapy, and the number of its colonies was significantly reduced in taurolidine-treated (p < 0.001) and gentamicin-treated (p < 0.01) subjects. There was no significant difference in terms of the irritating effects for all therapies tested (p > 0.05). CONCLUSIONS: Taurolidine solution with its unique properties is an effective antimicrobial agent for reducing the number of bacteria in the flora of the eye. Taurolidine appears to be well tolerated and offers promise as a potential new antimicrobial drug.     

万古霉素在不同病理状态兔眼内炎模型中药代动力学研究

目的 观察不同病理状态兔眼玻璃体内万古霉素的浓度和药代动力学参数.方法 健康成年白化兔81只,随机分为有晶状体细菌性眼内炎组(A组)、晶状体摘除手术后细菌性眼内炎组(B组)及晶状体摘除手术后眼内炎并行玻璃体切割手术组(C组),每组27只.所有兔右眼玻璃体腔注射浓度为10 mg/ml的万古霉素溶液1 ml.注射后0.5、2.0、4.0、6.0、12.0、24.0、48.0、72.0、84.0 h,每组注气处死3只兔,摘取眼球,收集玻璃体样品.采用高效液相色谱法(HPLC-UV)检测各组兔眼玻璃体内万古霉素浓度.应用3p 97药代动力学软件拟合并计算3组玻璃体内万古霉素的药-时曲线下面积(AUC)、清除率(CL)、半衰期(t1/2)及峰值浓度(Cmax)等药代动力学参数.结果 玻璃体腔注射万古霉素后各时间点,A组万古霉素浓度均高于治疗浓度.玻璃体腔注射后0.5、2.0、4.0、6.0、12.0h,B、C组万古霉素均维持较高浓度;玻璃体腔注射后24、48 h,浓度下降较快;玻璃体腔注射后72 h,浓度低于最低抑菌浓度.注射后不同时间点3组万古霉素浓度比较,A组与B、C组间差异均有统计学意义(P＜0.05);B、C组间差异无统计学意义(P＞0.05).A、B、C组万古霉素AUC分别为15 790.61、7643.94、7443.44 μg/(ml·h),CL分别为0.063、0.131、0.134ml/h,t1/2分别为13.49、7.15、6.93 h,Cmax分别为711.56、648.45、667.74μg/ml.A组与B、C组比较,万古霉素AUC较大(t=4.963,5.097;P＜0.01),CL较低(t=2.963,3.097;P＜0.05),t1/2较长(t=3.315,3.481; P＜0.01);但Cmax无明显差异(t=1.687,1.214;P＞0.05).结论 不同病理状态兔眼玻璃体内万古霉素的浓度及其药代动力学参数均存在一定差异.     

万古霉素在正常兔眼和细菌性眼内炎兔眼内的药代动力学研究

背景万古霉素近年来常被作为金黄色葡萄球菌性眼内炎治疗的首选药物,万古霉素在眼内药代动力学的研究报道较少。目的观察万古霉素在正常兔眼和细菌性眼内炎兔眼房水、玻璃体及血清中质量浓度的变化,并进行药代动力学参数比较。方法选取健康成年兔72只,采用随机数字表法分为正常组和眼内炎组,每组36只。眼内炎组兔右眼玻璃体腔内接种2000CFU／ml金黄色葡萄球菌建立眼内炎模型,注射后72h待出现典型的眼内炎表现时,兔眼玻璃体腔内注射10g／L万古霉素注射液0．1ml,分别于注射后0．5、2、4、6、12、24、48、72、84h经兔耳缘静脉采血2ml,之后以空气栓塞法处死动物,摘除眼球,收集房水和玻璃体,利用高效液相色谱仪紫外（HPLC—UV）法检测万古霉素在血液、房水和玻璃体内的质量浓度。3p97药代动力学软件拟合药代动力学参数。结果HPLC法的准确度和精确度符合生物样品的检测要求。玻璃体腔内注射万古霉素后,其在正常兔眼内的代谢呈二室模型,拟合曲线的高峰质量浓度Cmax分别为50．16mg／L和751．42mg／L,t1/2为51．04h和53．21h;其在金黄色葡萄球菌性眼内炎兔眼中代谢呈一室模型,高峰质量浓度Cmax分别为24．94mg／L和687．66mg／L,t1/2分别为11．42h和12．91h,2组动物血药质量浓度均较低,差异无统计学意义（P〉0．05）。正常组和眼内炎组玻璃体腔内注射万古霉素后随时间延长,玻璃体中万古霉素的质量浓度逐渐下降,而房水中出现先升高后下降的趋势。与正常组相应时间点比较,眼内炎组玻璃体和房水中万古霉素的质量浓度均明显下降,差异均有统计学意义（P〈0．05,P〈0．01）。结论HPLC能满足万古霉素药代动力学分析的需要;万古霉素在正常兔眼内的质量浓度较高,清除缓慢,而在细菌性眼内炎兔眼中质量浓度较低、清除较快。     

Treatment of experimental methicillin-resistant Staphylococcus epidermidis endophthalmitis with intravitreal vancomycin

Endophthalmitis remains a dreaded complication of intraocular surgery and penetrating eye trauma. Subconjunctival, topical, and systemic antibiotics have been largely ineffective in the treatment of endophthalmitis, whereas intravitreal antibiotics have proved efficacious. Methicillin-resistant Staphylococcus epidermidis has become an important pathogen in many infections, including endophthalmitis. Toxicity, clearance, and efficacy of intravitreal vancomycin were evaluated in the treatment of experimental methicillin-resistant S. epidermidis endophthalmitis. No evidence of retinal toxicity was found and therapeutic levels were demonstrated six days after injection. The treated rabbit eyes showed a marked beneficial effect when compared to the untreated eyes. If experience confirms the safety of intravitreal vancomycin in human eyes, vancomycin should be considered the drug of choice for methicillin-resistant S. epidermidis endophthalmitis.     

Effect of blood on susceptibility to Staphylococcal endophthalmitis

PURPOSE: The authors examined the effect of blood on susceptibility to experimental endophthalmitis. METHODS: Forty rabbits received an injection of 5-25 colony-forming units of Staphylococcus epidermidis into the vitreous of the right eye. Twenty of these same eyes received a subsequent intravitreal injection of 0.2 mL blood while the remaining 20 received an intravitreal injection of 0.2 mL of a salt solution. All eyes were examined daily for signs of endophthalmitis. Vitreous cultures were obtained on day 2 from 30 of the 40 rabbits. Twenty rabbits were assigned for culture and euthanasia at day 5 and those remaining were cultured and killed at day 7. RESULTS: In rabbits with blood and bacteria, 10 of 15 (67%) were culture positive at 2 days, compared to 2 of 15 (13%) that received salt solution and bacteria (P < 0.01). At days 5 and 7 there was no statistically significant difference in culture results. However, inflammatory scores were significantly higher at days 3-7 in rabbits with blood compared to those with salt solution (P 相似文献   

Effects of intravitreal moxifloxacin and dexamethasone in experimental Staphylococcus aureus endophthalmitis

PURPOSE: To evaluate the effects of intravitreal moxifloxacin and moxifloxacin and dexamethasone combination in an experimental rabbit model of Staphylococcus aureus endophthalmitis. METHODS: The right eyes of 24 rabbits weighing 2 to 3 kg were used. Ten thousand colony-forming units (CFU) of S. aureus in 0.1 ml saline solution were inoculated into the vitreous cavity. The eyes were randomly assigned to one of the four groups equally. Twenty-four hours after the inoculation of S. aureus, group 1 received 50 microg moxifloxacin, group 2 received 50 microg moxifloxacin plus 400 microg dexamethasone, and group 3 received 1 mg vancomycin intravitreally. No treatment was given to group 4. Clinical examination scores were recorded. Vitreous aspirates were obtained for microbiological analysis just before sacrifice, and the eyes were enucleated for histopathologic examination. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests. RESULTS: In all treatment groups, mean number of CFU and histopathologic score were significantly lower compared with control group (p<0.05), and the difference between treatment groups was not statistically significant (p>0.05). The clinical score was not significantly different between groups (p>0.05). CONCLUSIONS: Intravitreal injection of 50 microg moxifloxacin was effective in the treatment of S. aureus endophthalmitis. Bacteriological, histopathologic, and clinical outcomes after treatment using moxifloxacin, moxifloxacin and dexamethasone combination, and vancomycin were comparable. Intravitreal moxifloxacin may be an option in the treatment of S. aureus endophthalmitis.     

Vitrectomy for endophthalmitis after cataract surgery

PURPOSE: To identify risk factors of poor visual outcome with vitrectomy for early-onset endophthalmitis after cataract surgery. PATIENTS AND METHODS: Clinical records of 29 consecutive eyes with endophthalmitis developing within 6 weeks after cataract surgery and that underwent therapeutic vitrectomy between June 1996 and April 2001 were retrospectively reviewed. Twenty-two of the eyes received intravitreal injections of vancomycin and ceftazidime at the time of vitrectomy, and all patients received intravenous antibiotics. Eyes were divided into two groups; group A consisted of 22 eyes with a final visual acuity of 0.2 or greater, and group B consisted of 7 eyes with a final visual acuity of less than 0.2. RESULTS: Fifteen eyes (52%) in group A achieved a visual acuity of 0.5 or better and 8(28%) achieved a visual acuity of 1.0, while 4 eyes in group B developed phthisis bulbi. For eyes with a preoperative visual acuity of hand motions or worse, there was no correlation between final visual acuity and preoperative visual acuity. The overall culture-positive rate was 57%. In group A, methicillin-resistant Staphylococcus epidermidis was identified in 6 eyes, methicillin-resistant Staphylococcus aureus (MRSA) in 3 eyes and enterococcus in 2 eyes. In group B, alpha-hemolytic streptococcus (AHS) was identified in 4 eyes, aspergillus in 1 eye, and MRSA in 1 eye. All isolates were sensitive to vancomycin with the exception of the aspergillus. AHS infection appeared to be associated with wound failure from the initial cataract surgery and a poor visual outcome. Among 3 of the eyes that developed phthisis bulbi, intravitreal injection of antibiotics was not performed. CONCLUSION: Early vitrectomy and intravitreal injection of vancomycin may improve visual outcomes, but infection with AHS may be associated with cataract surgery wound failure and poor visual outcomes.     

Role of prophylactic intravitreal antibiotics in open globe injuries

PURPOSE: To determine the efficacy of prophylactic intravitreal antibiotics in reducing the incidence of endophthalmitis after trauma. METHODS: This was a prospective, randomised, case control study of 70 consecutive patients with open globe injury. The patients were prospectively randomised into group I (32 eyes) and group II (38 eyes). Group I patients were given prophylactic intravitreal injection of vancomycin 1 mg and ceftazidime 2.25 mg at the conclusion of primary repair. Group II patients were not given prophylactic intravitreal antibiotics. All the patients received intravenous ciprofloxacin. RESULTS: The incidence of endophthalmitis was higher in group II (7 of 38 eyes; 18.42%) compared to group I (2 of 32 eyes; 6.25%). Both the patients who developed endophthalmitis despite prophylactic intravitreal antibiotics in group I had an initially undetected intraocular foreign body (eyelash) in the vitreous cavity. CONCLUSIONS: Prophylactic intravitreal broad spectrum antibiotic injection decreases the risk of post-traumatic endophthalmitis.     

金黄色葡萄球菌和大肠埃希杆菌混合感染性兔眼内炎模型的建立

目的 建立外源性金黄色葡萄球菌和大肠埃希杆菌混合细菌性眼内炎动物模型，为进一步开发治疗复杂性眼内炎的新型药物打基础。 方法 新西兰白兔42只84眼，随机分组为混合细菌组、金黄色葡萄球菌组和大肠埃希杆菌组等3个实验和1个生理盐水对照组，每组21眼。实验组分别玻璃体腔注射0.1 ml的2×104 CFU/ ml的混合细菌悬液（含金黄色葡萄球菌和大肠埃希杆菌各103）、104 CFU/ ml的金黄色葡萄球菌悬液和104 CFU/ml大肠埃希杆菌悬液，对照组注射0.1ml无菌生理盐水。分别于注射后6、12、24、48、72 h和7 、14 d行裂隙灯显微镜、检眼镜、眼部A/B超和视网膜电图（ERG）检查；同时各眼抽取玻璃体液0.1 ml做细菌鉴定和计数，后剖取眼球做组织病理学观察。 结果 临床观察发现，3个实验组注射后均有不同程度的炎症反应，而总变化趋势趋于一致，混合细菌组在注射后12 h出现明显的前房渗出等炎症反应，较金黄色葡萄球菌组和大肠埃希杆菌组早，48 h～72 h最重，4～7 d炎症反应开始缓慢减轻，10～14 d炎症明显减轻，角膜出现新生血管，玻璃体呈灰白色混浊。细菌培养发现，混合细菌组6 h～14 d阳性率为100%；金黄色葡萄球菌组6～72 h阳性率为100%，7～14 d阳性率为0；大肠埃希杆菌组6 h～7 d阳性率为100%，14 d阳性率为67.67%；对照组6 h～14 d阳性率为0。ERG检查，注射后各实验组在48 h后b波波幅均消失，生理盐水组ERG-b波波幅下降小于30%。病理学检查，注射后各实验组表现为眼内各组织的炎细胞浸润。 结论 通过兔眼玻璃体腔注射金黄色葡萄球菌和大肠埃希杆菌的方法成功建立了稳定的混合细菌所致的复杂性眼内炎模型。     

玻璃体腔注射阿霉素和万古霉素治疗眼球穿孔伤并发症的实验研究

目的观察玻璃体腔注射阿霉素和万古霉素对感染性眼内炎及外伤性增生性玻璃体视网膜病变（PVR）的抑制效果。方法40只新西兰白兔随机分为4组,每组10只。右眼建立外伤性出血性眼球穿孔伤模型,左眼为空白对照眼。4个组中生理盐水组,玻璃体腔注射生理盐水0．1mL;阿霉素组,注射阿霉素2．5μg（0．1mL）;万古霉素组,注射万古霉素1．0mg（0．1mL）;联合用药,注射阿霉素2．5μg（0．1mL）及万古霉素1．0mg（0．1mL）。以裂隙灯显微镜观察眼前段炎症情况,炎症持续超过2周者行玻璃体微生物学培养;直接检眼镜观察外伤性PVR情况。结果联合用药组PVR程度低于生理盐水组（P=0．023）及万古霉素组（P=0．034）;生理盐水组、阿霉素组各发生细菌性眼内炎2例（20．0％）;万古霉素组、联合用药组未见细菌性眼内炎发生。结论在外伤性出血性眼球穿孔伤动物模型中,玻璃体腔注射阿霉素可能降低外伤性PVR程度;而玻璃体腔注射万古霉素可能降低感染性眼内炎症发生率。     

头孢哌酮/舒巴坦玻璃体腔注射治疗兔铜绿假单胞菌性眼内炎

目的评价头孢哌酮/舒巴坦治疗铜绿假单胞菌眼内炎的疗效。方法青紫蓝兔18只,随机分为3组,右眼注菌后6h分别注入100g/L头孢哌酮/舒巴坦、22.5g/L头孢他啶和生理盐水各0.1mL,观察24h。另取青紫蓝兔12只,随机分为2组。早期注药组注菌后6h注入100g/L头孢哌酮/舒巴坦0.1mL,晚期注药组注菌后20h注入100g/L头孢哌酮/舒巴坦0.1mL,观察1周。结果头孢哌酮/舒巴坦组、头孢他啶组与生理盐水组比较除角膜评分外（P〉0.05）,结膜、前房、玻璃体、视网膜、B型超声检查及组织病理学评分结果差异均有统计学意义（P〈0.05）;头孢哌酮/舒巴坦组与头孢他啶组相比,除虹膜炎症反应评分差异有统计学意义外（P〈0.05）,其他评分差异均无统计学意义（P〉0.05）,但从具体评分来看头孢哌酮/舒巴坦组优于头孢他啶组。早期注药组与晚期注药组相比,1周后结膜、前房、虹膜、玻璃体、视网膜、B型超声检查及组织病理学评分差异均有统计学意义（P〈0.05）。结论 100g/L头孢哌酮/舒巴坦0.1mL玻璃体腔注射治疗早期铜绿假单胞菌眼内炎有效。     

Endophthalmitis caused by staphylococcus epidermidis: in vitro antibiotic susceptibilities and clinical outcomes.

BACKGROUND AND OBJECTIVE: To investigate the antibiotic sensitivities and clinical outcomes of eyes with endophthalmitis caused by methicillin-sensitive versus methicillin-resistant Staphylococcus epidermidis (MSSE/MRSE). PATIENTS AND METHODS: A retrospective, consecutive case series of all patients with endophthalmitis caused by S. epidermidis from January 1, 1996, through July 1, 2004, was conducted. The antibiotic sensitivities and clinical outcomes were obtained from the corresponding medical records. RESULTS: The study included 86 eyes of 86 patients with S. epidermidis endophthalmitis (34 MSSE and 52 MRSE). Endophthalmitis categories included cataract surgery (58), glaucoma surgery (12), trauma (7), vitrectomy (4), penetrating keratoplasty (4), and corneal suture ulcer (1). In vitro testing revealed that all MSSE and MRSE isolates were sensitive to vancomycin, 67% of MSSE isolates and 67% of MRSE isolates were sensitive to gatifloxacin, and 73% of MSSE isolates and 67% of MRSE isolates were sensitive to moxifloxacin (overall 68% sensitive). All eyes were treated with intravitreal vancomycin and either ceftazidime or amikacin. Visual acuity improved to a median of 20/80 at 3 months and 20/60 at 1 year. I CONCLUSIONS: In the current study, all MSSE and MRSE isolates were sensitive to vancomycin and 68% were sensitive to the fourth-generation fluoroquinolones. There were no significant differences in visual acuity outcomes of endophthalmitis caused by MSSE versus MRSE isolates.