In vitro susceptibility of filamentous fungi to itraconazole.

The in vitro activity of itraconazole was investigated against 25 clinical isolates of filamentous fungi by agar dilution method. The isolated included Aspergillus sp., hyalohypomycetes, dematiaceous fungi and zygomycetes. Intraconazole was more active, inhibiting 50% (MIC 50) and 90% (MIC 90) of the Aspergillus sp., at a concentration of 0.5 and 2.5 ug ml-1 (MIC range 0.1 and 5 micrograms ml-1) Ketoconazole (MIC range 0.5-10 ug ml-1) required 1 and 5 ug ml-1 for inhibiting 50% and 90% of the isolates. For the hyalophypomycetes and dematiaceous fungi, the MIC 50s for itraconazole were 1 and 0.5 ug ml-1 and Ketoconazole required 2.5 ug ml-1 for both the groups. For the zygomycetes, the MIC range and MIC 50s for Ketoconazole were 1-100 and 10 ug ml-1 whereas the values for itraconazole were 5- > 100 and > 100 micrograms ml-1.