Efficacy of Amphotericin B Against Fusarium and Aspergillus in Corneal Storage Medium

Abstract

Purpose: The incidence of postkeratoplasty fungal infection is increasing in the United States, and our most commonly used corneal storage medium, Optisol-GS, contains antibiotics but no antifungal agents. We previously demonstrated the efficacy of amphotericin B additives in eliminating Candida albicans contaminants in Optisol-GS. The purpose of this study was to determine whether amphotericin B would also be efficacious against Fusarium solani and Aspergillus fumigatus.

Methods: Vials of Optisol-GS were supplemented with 0.255 μg/mL of amphotericin B. Half of the vials were inoculated with F. solani and half with A. fumigatus. Positive control vials were inoculated with the fungi but no amphotericin B. The vials were refrigerated, sampled, and plated at different time points. The plates were then incubated at 36°C for 48 hr after which fungal colony counts were performed.

Results: There was an average reduction in the growth of F. solani in the amphotericin B-supplemented vials of 44% on day 2, 79% on day 7, and 80% on day 14 when compared with the positive control vials. There was an average reduction in the growth of A. fumigatus in the amphotericin B-supplemented vials of 40% on day 2 and 14% on day 7 when compared with the positive control vials. Both amphotericin B-supplemented and control vials grew less than 2 colonies of A. fumigatus on day 14.

Conclusions: This study suggests that amphotericin B additives in Optisol-GS reduce the growth of F. solani and A. fumigatus.