CHEMOTHERAPY OF EXPERIMENTAL KERATOMYCOSIS

An experimental model for mycotic keratitis was developed in pigmented rabbits, utilizing 5,000 spores of Aspergillus fumigatus or 1,000,000 yeast forms of Candida albicans as the inoculum. Forty-eight hours after intralamellar injection of the inoculum, corneal ulcers were observed, and treatment with various antifungal agents was initiated and continued every two hours around the clock for nine treatment days. During and after the treatment period all corneas were evaluated for iritis, perforations, hypopyons and degree of ulceration. The results showed that heavy metals, detergents and ionic solutions were ineffective in reducing the keratomycotic process. Pimaricin and amphotericin B were therapeutically effective against both infections, while nystatin was effective only against C. albicans and A. fumigatus. It was also found that addition of potassium iodide to these compounds produced an additive effect, resulting in increased corneal clarity and in a decreased incidence of iritis and hypopyon formation. Because of the innocuous nature of pimaricin, we believe that the most efficacious treatment of mycotic keratitis is a 5% pimaricin suspension containing 2% potassium iodide applied topically every two hours around the clock. © 1969.