In vitro antifungal susceptibility and molecular identity of 99 clinical isolates of the opportunistic fungal genus Curvularia

Abstract The in vitro antifungal susceptibility of a set of 99 clinical isolates of Curvularia was tested against 9 drugs using a reference microdilution method. The isolates had been identified previously to species level by comparing their ITS rDNA and glyceraldehyde-3-phosphate dehydrogenase gene sequences with those of reference strains. We were able to reliably identify 73.2% of the isolates, the most frequent species being Curvularia aeria , Curvularia geniculata / Curvularia senegalensis , Curvularia lunata , Curvularia inaequalis , Curvularia verruculosa , and Curvularia borreriae . Most of these isolates had been recovered from nasal sinus, which is generally considered one of the most frequent sites of infection by these fungi. In addition, at least 3 phylogenetic species that have not yet been formally described were detected. The most active drugs were the echinocandins, amphotericin B, and posaconazole, whereas voriconazole and itraconazole showed poor activity.