Comparison Therapeutic Effects of Ciprofloxacin, Silver Nanoparticles and Their Combination in the Treatment of Pseudomonas keratitis in Rabbit: An Experimental Study

Pseudomonas aeruginosa is one of the most common causes of keratitis. The current study was done to evaluate the therapeutic effects of antibacterial combinations with Silver nanoparticles (Ag-NPs) and Ciprofloxacin in experimental Pseudomonas keratitis. Sixty four New Zealand rabbits were prepared. All rabbits were randomly categorized into eight groups (each group containing eight rabbits): Control +, Control -, Ciprofloxacin, Ag-NPs, Ciprofloxacin plus Betamethasone, Ag-NPs plus Betamethasone, Ciprofloxacin plus Ag-NPs, and Ciprofloxacin plus Ag-NPs plus Betamethasone. Twelve hours after bacterial inoculation into the cornea, the eyes were examined daily to evaluate the number of days of ocular discharge and blepharospasm. Also, after 108 and 204 h, first grading of corneal opacity was done and then four rabbits of each groups were euthanized for bacterial count. The results showed that the means of days of blepharospasm, ocular discharge, and bacterial counts (log CFU mL(-1)) were significantly different in the treatment groups at 108 and 204 h (P <0.0005, ANOVA). According to Tukey's test, Ciprofloxacin plus Ag-NPs plus Betamethasone group was significantly less than Control +, Ag-NPs, and Ag-NPs plus Betamethasone groups for these variables (P < 0.05). The mean rank of opacity scores was significantly different between treatment groups (P = 0.01, Krnskal-Wallis). Mann-Whitney U-test revealed that Ciprofloxacin plus Ag-NPs plus Betamethasone group had significantly better score than Control +. Ag-NPs, and Ag-NPs plus Betamethasone groups (P < 0.05). It seems Ag-NPs can be an appropriate adjuvant for Ciprofloxacin, but due to the results they can't be an alternative for Ciprofloxacin to treat Pseudomonas keratitis.