In vitro susceptibility of filamentous fungal isolates from a corneal ulcer clinical trial

Abstract

Purpose To describe the minimum inhibitory concentration (MIC) of fungal isolates to natamycin and voriconazole, and to compare these MICs to previous ocular susceptibility studies. Design Experimental laboratory study using isolates from a randomized clinical trial. Methods The Mycotic Ulcer Treatment Trial I was a randomized, double-masked, multicenter trial comparing topical natamycin and voriconazole for fungal keratitis treatment. Susceptibility testing to natamycin and voriconazole were performed according to Clinical and Laboratory Standards Institute methods. The relationship between organism and MIC was assessed. A literature review was performed to compare results to previous ocular susceptibility studies. Results Of the 323 patients enrolled in the trial, MICs were available for 221 (68%). Fusarium (n = 126) and Aspergillus species (n = 52) were the most commonly isolated organisms. MICs to natamycin and voriconazole were significantly different across all genera (P