Elsevier

Ophthalmology

Volume 110, Issue 10, October 2003, Pages 1946-1951
Ophthalmology

Original article
Antibiotic resistance patterns of ocular bacterial flora: A prospective study of patients undergoing anterior segment surgery

Presented in part at the Association for Research in Vision and Ophthalmology, Fort Lauderdale, Florida, May 2002.
https://doi.org/10.1016/S0161-6420(03)00735-8Get rights and content

Abstract

Purpose

To determine the antibiotic susceptibility patterns of conjunctival bacterial flora isolated preoperatively from patients undergoing anterior segment surgery.

Design

Prospective observational study.

Participants

One hundred fifty-six eyes from 139 patients scheduled for anterior segment surgery were enrolled over a 6-month period from August 2001 to February 2002.

Methods

Conjunctival cultures were obtained on the day of surgery before povidone-iodine or antibiotic application.

Main outcome measures

Bacterial isolates were identified and tested for antibiotic susceptibility using the Kirby-Bauer disc-diffusion technique.

Results

Among the 156 eyes studied, 36 were from patients who had undergone either bilateral surgery or more than one surgery in the same eye. Only the first eyes of the 120 patients that underwent initial ocular surgery were included in our analysis. Of these 120 eyes, 21 (18%) showed no bacterial growth. Of the 143 bacterial strains isolated from the remaining 99 eyes, 112 (78%) were coagulase-negative staphylococci (CNS). Among the CNS, greater than 90% were susceptible to cefotaxime, levofloxacin, imipenem, meropenem, vancomycin, and each of the aminoglycosides except neomycin. Between 70% and 90% of the CNS were susceptible to cefazolin, neomycin, ciprofloxacin, ofloxacin, norfloxacin, and chloramphenicol. Less than 70% of the isolated CNS were sensitive to the penicillin analogues, ceftazidime, erythromycin, and tetracycline.

Conclusions

Preoperative conjunctival isolates of CNS seem to be most sensitive to vancomycin, the aminoglycosides (except neomycin), and levofloxacin.

Section snippets

Patients and methods

All patients scheduled for anterior segment intraocular surgery at Stanford University were asked to participate in this prospective study. After obtaining approval from the Institutional Review Board at Stanford University, consecutive patients who gave consent participated in the study. A total of 156 eyes from 139 patients were enrolled in the study from August 2001 to February 2002. Patients receiving topical ophthalmic medications or systemic antibiotics were not excluded from the study,

Results

Among the 156 patients participating in the study, 17 had surgery in both eyes. To avoid paired bias, only the first operated eye of each patient was included in the data analysis. Furthermore, 19 patients had more than one surgery in the same eye, and, therefore, only the first surgery was included in the study, yielding 120 eyes from 120 patients. The mean and median ages of study participants were 69.3 and 73.0 years, respectively. There were 53 male and 67 female patients. Of the 120 eyes,

Discussion

One of the goals of postoperative endophthalmitis prophylaxis is to reduce the number of eyelid and conjunctival bacteria that are present at the time of surgery. It has been shown that preoperative application of both topical povidone-iodine and various antibiotic agents is effective in reducing the incidence of ocular contamination as measured by the growth of bacterial colonies in conjunctival isolates.2, 3, 4, 12, 13, 14, 15, 16, 17 Most cataract surgeons in the United States place their

References (31)

  • S.R. Grimes et al.

    Preoperative antibiotic and povidone-iodine preparation of the eye

    Ann Ophthalmol

    (1991)
  • T.J. Liesegang

    Use of antimicrobials to prevent postoperative infection in patients with cataracts

    Curr Opin Ophthalmol

    (2001)
  • A. Graves et al.

    In vitro susceptibilities of bacterial ocular isolates to fluoroquinolones

    Cornea

    (2001)
  • M.H. Goldstein et al.

    Emerging fluoroquinolone resistance in bacterial keratitisa 5-year review

    Ophthalmology

    (1999)
  • F. Schaefer et al.

    Bacterial keratitisa prospective clinical and microbiological study

    Br J Ophthalmol

    (2001)
  • Cited by (0)

    Manuscript no. 220611.

    Supported by the Edward E. Hills Foundation, San Francisco, California, and Hannelore-Georg Zimmerman Foundation, Munich, Germany.

    The authors have no proprietary interest in any of the products used in this study.

    View full text