Effects of methylprednisolone and cyclosporine A on fungal growth in vitro

Abstract

Purpose: The management of corneal transplants after mycotic keratitis often poses a therapeutic dilemma. Clinicians are hesitant to use topical steroids because of their potential enhancement of fungal growth. This study seeks to evaluate the in vitro effects of methylprednisolone and cyclosporine A on the growth of various molds that often are responsible for keratomycoses.

Methods: Fusarium oxysporum, Fusarium solani, and Aspergillus fumigatus were grown in the presence of varying concentrations of methylprednisolone, cyclosporine A, and vehicle controls. Fungal growth was evaluated in a masked fashion based on the number of colonies and their morphologies.

Results: All tested concentrations of cyclosporine A (1%, 2%, 4%) had a statistically significant suppressive effect on the growth of F. oxysporum (p<0.001) and F. solani (p<0.001) compared with methylprednisolone and vehicle control solutions. A dose-dependent decrease in the number of colonies grown also was noted for F. oxysporum (p<0.001) and F. solani (p<0.001). In the case of A. fumigatus, cyclosporine A significantly decreased the colony size (p<0.015) in a dose-dependent fashion.

Conclusions: Cyclosporine A appears to have an inhibitory effect on fungal growth in vitro. Cyclosporine A may be an important alternative to topical steroids for management of corneal transplants after mycotic keratitis.