Intravitreal taurolidine against experimental Staphylococcus epidermidis endophthalmitis in rabbits

Taurolidine is a broad spectrum, non-antibiotic antimicrobial agent, not previously tested against infectious endophthalmitis. The efficacy of intravitreal taurolidine in the treatment of experimental Staphylococcus epidermidis endophthalmitis was evaluated and compared with vancomycin in a rabbit model.

The right eyes of 34 albino rabbits were infected with an intravitreal inoculum of S. epidermidis (10(5) colony-forming units/0.1 ml). The right eyes of four rabbits (group 7) were not infected and served as uninfected controls. 24 hours after inoculation of bacteria the animals were divided into the following treatment groups: group 1 (7 rabbits) received intravitreal taurolidine at 24 hours and group 2 (7 rabbits) received at 48 hours. Group 3 (7 rabbits) received vancomycin at 24 hours and group 4 (7 rabbits) at 48 hours. Group 5 (3 rabbits) received polyvinylpyrrolidone at 24 hours and group 6 (3 rabbits) at 48 hours. Clinical scoring was performed at 24, 48 and 72 hours. At 72 hours post inoculation, vitreous samples were collected for quantitative microbiological studies and then, the eyes were enucleated for histopathological scorings.

The clinical and histopathological examinations revealed significant amelioration of inflammation in eyes treated with taurolidine and vancomycin when compared with polyvinylpyrrolidone. The eyes treated with taurolidine also had significantly lower colony forming units than the eyes treated with polyvinylpyrrolidone and taurolidine rendered many eyes sterile.

Taurolidine is expected to be a potential agent for treatment of S. epidermidis endophthalmitis.