In vitro activity of antifungal agents against clinical isolates of aspergilli

The growth-inhibitory effect of 9 antifungal agents against 32 strains of aspergilli belonging to 10 species was studied. MIC values were determined in a microtiter dilution method using Brain Heart Infusion Broth (polyenes, azoles) and a medium with Yeast Nitrogen Base (5-flucytosine). Saperconazole was the most active agent against all isolates tested, the growth of 90% being inhibited at a concentration of 0.09 mg l-1. The susceptibility profile of individual species differed only little, with the exception of high MIC values of polyenes in A. terreus. Nine isolates (28%) were resistant to 5-flucytosine. The intra-species variation of susceptibility studied in A. fumigatus was only little pronounced.