In vitro activity of seven azole compounds against some clinical isolates of non-dermatophytic filamentous fungi and some dermatophytes

The in vitro activity of seven azole compounds viz clotrimozole, isoconazole, bifanazole, fluconazole oxyconazole, Bay n 7133 and Bay L 9139 was investigated against 47 clinical isolates of pathogenic non-dermatophytic filamentous fungi and dermatophytic fungi. The isolates included Hendersonula toruloidea-26, Scytalidium hyalinium-5, Scytalidium japonicum-1, Trichophyton rubrum-5, Trichophyton tonsurans-3, Trichophyton mentagrophytes var. mentagrophytes-4, Epidemophyton floccosum-2, Microporum gypseum-2 isolates. The drugs were significantly more active against the dermatophytes (MIC range 0.025–1.56 g/ml) than non-dermatophytes (MIC range 0.39–6.25 g/ml). Isoconazole showed more activity than the rest of the azole compound tested. Clotrimazole, fluconazole, oxyconazole, bifonazole were comparable in their inhibitory activity against both dermatophytes and non-dermatophytes. The azole derivatives, Bay n 7133 and Bay L 9139 showed higher MIC range i.e. gave a range of 0.39–1.56 g/ml for dermatophytes and 1.56–6.25 g/ml for non-dermatophytic filamentous fungi. The minimal fungicidal concentration (MFC) of all the drugs tested were mostly within 2–8 times their MIC values.