Intravitreal penetration of teicoplanin

Effect of vancomycin, teicoplanin, and cefuroxime on Staphylococcus epidermidis adherence to intraocular lenses

PURPOSE

To compare the adherence of Staphylococcus epidermidis on AcrySof (Alcon) and poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) treated with vancomycin, teicoplanin, and cefuroxime.

SETTING

Kocaeli University, School of Medicine, Kocaeli, Turkey.

METHODS

The lenses were contaminated with S epidermidis solutions containing 10(8) colony-forming units. Intraocular lenses were placed in sterile triptic soy broth after being held in antibiotic solutions for 15 minutes. After that, sonication and vortex procedures were performed to remove all the attached bacteria that could not be removed by antibiotics. Ten microliters from each broth were taken and inoculated into sheep blood agar. The colonies were counted overnight. The statistical analyses were made using Mann-Whitney U and Kruskal-Wallis tests, and a P value less than 0.05 was considered statistically significant.

RESULTS

Regarding the inhibitory effect of antibiotics on bacterial adhesion, there was no statistically significant difference between AcrySof and PMMA lenses. In the cefuroxime group, the mean numbers of colony-forming units on AcrySof and PMMA lenses were 35.2 +/- 6.94 and 30.8 +/- 18.69, respectively (P>.05). In the teicoplanin group, the mean number of colony-forming units on AcrySof lenses was 100.1 +/- 20.97 and 70.6 +/- 43.75 on the PMMA lenses. The adherence in the vancomycin group was 245 +/- 273.74 colony-forming units for AcrySof lenses and 159.8 +/- 101.94 for PMMA lenses (P>.05). Regarding the inhibitory effect of antibiotics, cefuroxime was the most effective, followed by teicoplanin and vancomycin, respectively. Overall, the mean numbers of colony-forming units on the lenses that were held in cefuroxime, teicoplanin, and vancomycin solutions were 33.0 +/- 13.90, 85.35 +/- 36.66, and 202.4 +/- 205.74, respectively (P = .000).

CONCLUSIONS

The results suggest that cefuroxime, teicoplanin, and vancomycin significantly inhibit bacterial adherence to IOLs. The effect of cefuroxime on adherence inhibition was significantly higher than that of teicoplanin and vancomycin. Bacterial adherence is an important factor in bacterial virulence. Antibiotics, especially cefuroxime, can successfully inhibit bacterial adherence.

Surveillance of endophthalmitis following cataract surgery in the UK

AIMS

To estimate the incidence of acute-onset presumed infectious endophthalmitis (PIE) following cataract surgery in the UK and provide epidemiological data on the presentation, management, microbiology, and outcome of cases of endophthalmitis.

METHODS

Cases were identified prospectively by active surveillance through the British Ophthalmological Surveillance Unit reporting card system, for the 12-month period October 1999 to September 2000 inclusive. Questionnaire data were obtained from ophthalmologists throughout the UK at baseline and 6 months after diagnosis. Under-reporting was estimated by independently contacting units with infection databases.

RESULTS

Data were available on 213 patients at baseline and 201 patients at follow-up. The minimum estimated incidence of PIE was 0.086 per 100 cataract extractions and the corrected incidence was 0.14 per 100 cataract extractions. For the management of PIE, 96% of patients received intravitreal, 30% subconjunctival, 65% oral, and 17% intravenous antibiotics. In all, 17% of patients received intravitreal steroid. From the intraocular samples taken for microbiological analysis, 56% were culture positive. At follow-up, 48% of patients achieved visual acuity of 6/12 or better and 66% achieved better than 6/60. 13% of patients were unable to perceive light or had evisceration of the globe.

CONCLUSIONS

The incidence of PIE after cataract surgery in the UK is comparable to that of other studies. Approximately 50% of patients achieved a visual acuity close to the driving standard.