Comparison of efficacy of topical and oral fluconazole treatment in experimental Aspergillus keratitis

Purpose. To investigate the therapeutic role of topical and oral fluconazole treatment using a rabbit model of Aspergillus fumigatus keratitis. Methods. Aspergillus fumigatus spores were injected into the corneal stroma of the right eye of 20 rabbits. Forty-eight hours later the rabbits were randomly divided into three groups. Group 1 rabbits (six) were treated with topical fluconazole (2 mg/ml, eight times daily), group 2 rabbits (seven) received oral fluconazole (37.5 mg/kg bid), and group 3 rabbits (seven) were untreated controls. The eyes were examined and photographed with a slit-lamp 2, 6, 10, 16, and 20 days after inoculation and an observer graded the corneas in a masked fashion. Corneal cultures were taken on days 2, 14, and 20 for fungus growth. Results. At the beginning of treatment, the slit-lamp scores did not differ among three groups. However, on days 6, 10, 16, and 20 the treated groups had statistically significant lower scores compared to the untreated controls. No significant difference was observed between topical and oral treated groups at any examination point. All cultures were positive on day 2, but on days 16 and 20, there were significantly lower positive fungal cultures in both treatment groups compared to the control (p < 0.01, chi square test). Conclusion. Our study showed that both topical and oral fluconazole were effective in lessening the severity of fungal keratitis in a rabbit model and should be considered effective treatment alternatives in the therapy of Aspergillus fumigatus keratitis.