Effect of Intravitreal Ciprofloxacin in the Treatment of Experimental Bacillus Endophthalmitis

ABSTRACT

PURPOSE: Bacillus cereus is an important cause of post-traumatic endophthalmitis. Several different anti-biotics have been used to prevent permanent visual loss. The authors compared the efficacy of intravitreal vancomycin and ciprofloxacin in the treatment of experimental Bacillus cereus endophthalmitis. METHODS: Forty eyes of 20 white rabbits were inoculated with B. cereus organisms. Ten eyes were randomized to receive intravitreal vancomycin (group 1) and 10 eyes ciprofloxacin (group 2) after 12 or 24 hours. Fellow eyes were injected with normal saline as control group. After 48 hours, the eyes were examined and graded for clinical signs of infection and enucleated for histologic examination. RESULTS: There was a statistically significant difference in clinical features between treated groups and control group (p<0.05). There was no significant difference between vancomycin-treated group and ciprofloxacin-treated group. Compared to eyes treated 12 hours after inoculation, eyes treated 24 hours after inoculation showed worse clinical gradings (p<0.05). Histologic examination showed vancomycin or ciprofloxacin-treated groups had significant less inflammation and tissue destruction than control group (p<0.05). There was a statistically significant difference in vitreous and retinal structure between ciprofloxacin-treated after 12 hours inoculation and 24 hours inoculation group (p<0.05). CONCLUSIONS: Ciprofloxacin appeared to be limiting inflammation and tissue destruction in experimental Bacillus endophthalmitis and might effective in substitute vancomycin when necessary.