Effect of intravitreal triamcinolone acetonide in the treatment of experimental Staphylococcus epidermidis endophthalmitis.

PURPOSE

To investigate the effect of intravitreal injection of triamcinolone acetonide (TA) in the treatment of experimental Staphylococcus epidermidis endophthalmitis.

MATERIALS AND METHODS

Experimental endophthalmitis induced in one eye of 38 rabbits by intravitreal injection of Staphylococcus epidermidis. The infected rabbits were randomly divided into three groups. The rabbits in group 1 (n = 15) received intravitreal injection of 1 mg vancomycin hydrochloride. Group 2 eyes (n = 15) received intravitreal TA (4 mg) plus vancomycin hydrochloride (1 mg). Group 3 eyes (8 eyes) received normal saline. Clinical examination in each group was performed two, seven, and 15 days after inoculation of the bacteria. The eyes were enucleated for histopathologic evaluation on the 15th day. Clinical and histological scoring systems were used to evaluate clinical and histological severity of the intraocular infection.

RESULTS

The mean clinical scores of three study groups at the 7th day were 5.8 +/- 2.3, 3.3 +/- 1.5, and 9.5 +/- 2.1, respectively. The mean of this value at 15th day were 6.2 +/- 2.6, 3.9 +/- 2.1, and 10 +/- 2.2, respectively. At the 7th and 15th day, the mean clinical score of group 2 was significantly lower when compared with the other two groups. Mean histopathologic scores of group 1, group 2, and group 3 were 11 +/- 2.7, 7.9 +/- 2.9, and 14.0 +/- 3.1, respectively. Histopathologic studies revealed less tissue destruction for eyes treated with TA. There was a significant positive correlation between the severity of clinical signs and pathologic damage in all three experiment groups; however, it was weakest in the IVTA treated group.

CONCLUSION

A standard clinical dose of intravitreal TA attenuates the clinical signs and tissue destruction in a rabbit model of Staphylococcus epidermidis endophthalmitis.