Abstract
Purpose:
The purpose of this study is to report the spectrum of gram-positive organisms causing culture-proven endophthalmitis and their susceptibilities to current antibiotics.
Methods:
Medical records were reviewed of all cases with culture-proven endophthalmitis at a single institution from January 2012 to September 2013. The outcome measures included all intravitreal isolates identified as well as antibiotic susceptibilities.
Results:
A total of 30 gram positive organisms were isolated from vitreous specimens during the study period. The most common organisms identified were the following: Staphylococcus epidermidis 60% (18/30); Streptococcus viridians and Streptococcus pneumonia 6.7% (2/30); Staphylococcus aureus 13.3% (4/30), Streptococcus mitis and Staphylococcus hominis 3.3% (1/30). For these organisms, overall susceptibilities were the following: vancomycin, 92.08 % (25/30 organisms susceptible); gentamicin, 90.9% (23/30 organisms susceptible); sulfamethoxazole/trimethoprim, 75.9% (25/30 organisms susceptible); linezolid 100% (27/30 organisms susceptible); moxifloxacin 47.68% (27/30 organisms susceptible); erythromycin 41.75% (24/30 organisms susceptible); ciprofloxacin 47.5% (23/30 organisms susceptible). Staphylococcus epidermis demonstrated the overall highest MICs, specifically in regards to Vancomycin, when compared to other organisms.
Conclusions:
The current study demonstrates resistance to commonly used medications. Future concerns regarding increased resistance among the most common isolated organisms are demonstrated when compared to a historical pattern.
Keywords: 513 endophthalmitis •
422 antibiotics/antifungals/antiparasitics