The Charles T. Campbell Eye Microbiology Lab
UPMC | University of Pittsburgh Medical CenterUniversity of Pittsburgh Schools of the Health Sciences
HomeAbout UsLab Diagnostic TestingAntibiotic SusceptibilityAntimicrobial TherapyCurrent ResearchContact Us

2007 OMIG, Abstract 14

OMIG Main Page | 2007 Abstracts | < Previous| Next >

Topical Gatifloxacin 0.3% Can Prevent Staphylococcus aureus-Induced Clinical Endophthalmitis in a Clear Cornea Incision Rabbit Model.
R.P. Kowalski, E.G. Romanowski, F.S. Mah, K.A. Yates, H. Weirback, L. Zhang, Y.J. Gordon.
The Charles T. Campbell Laboratory, University of Pittsburgh, Pittsburgh, PA

Purpose: Topical antibiotic prophylaxis may be necessary to reduce the likelihood of bacteria from the ocular surface entering the anterior chamber through a clear corneal incision during and following cataract surgery. This study evaluated the potential of topical gatifloxacin 0.3% to prevent endophthalmitis after a clear corneal incision was challenged topically with Staphylococcus aureus.
Methods: Topical drops of gatifloxacin 0.3% (Zymar ® , Allergan, Irvine, CA) or saline were instilled every 15 minutes for one hour (5 drops) into the right eye of 10 rabbits. After appropriate systemic and topical anesthesia, clear corneal incisions (using a 2.5 mm angled bibeveled  keratome) were created concurrently with a topical application of S. aureus (2.1 x 108 cfu  per 0.1 ml) (Gatifloxacin MIC = 0.5 µg/ml). A drop of gatifloxacin or saline was immediately applied post bacterial challenge, and 4 more topical drops were applied over the next 24 hours. At 24 hours post incision, the animals were examined in a masked fashion (YJG) with slit lamp for clinical signs of endophthalmitis (ocular discharge, conjunctivitis/scleral injection, limbal injection, hypopyon, iritis, anterior chamber cells, anterior chamber flare, corneal infiltration, and fibrin production) using a severity scale (0 to 3). The animals were sacrificed, and the aqueous and vitreous were tapped for bacteria colony counts. The data were analyzed using the Fisher’s Exact Test (FET) and Mann-Whitney tests.
Topical gatifloxacin 0.3% significantly reduced the clinical presentation of endophthalmitis in rabbits eyes [1/10 (10%) vs. 8/10 (80%) saline control, (p= 0.005) (FET)] following clear corneal incision and bacterial challenge. The total median clinical score for rabbits treated with gatifloxacin (2.25) was significantly (p= 0.0065, Mann-Whitney) lower than rabbits treated with saline (11.0). Only the aqueous humor of 2 rabbits treated with saline was positive for S. aureus.
Conclusions: Topical gatifloxacin 0.3% was able to prevent the clinical presentation of endophthalmitis in a clear corneal incision/S. aureus challenge rabbit model. This new model may also serve as an important tool for evaluating future anti-infectives for surgical prophylaxis.

This project was supported with an unrestricted grant by Allergan.   

Disclosusre code:  F,C


OMIG Main Page | 2007 Abstracts | < Previous| Next >

Top of Page

Web Site Terms of Use | E-mail Terms of Use | Medical Advice Disclaimer
UPMC | Affiliated with the University of Pittsburgh Schools of the Health Sciences | Contact UPMC