IN-VITRO SUSCEPTIBILITY TESTS OF DERMATOPHYTES TO GRISEOFULVIN AND IMIDAZOLE DERIVATIVES

The sensitivity of dermatophytes (89 ''wild'' and 38 ''collections'' s trains) to griseofulvin and azole derivatives (clotrimazole, cetoconaz ole, tioconazole, miconazole, econazole, isoconazole and oxiconazole) was studied using ''in vitro'' determinations of minimum inhibitory co ncentration (MIC) and minimum fungicidal concentration (MFC). Tile bro th dilution method was used, the antifungal drugs were used in concent rations between 0,05 to 100 mu g/ml. The inoculum was (standardized ad justing the suspension to contain) 1,0 to 1,5 x 10(6) ufc/ml. The MIC and MFC values showed different results for many fungi strains and dif ferent concentrations of antifungal agents. The values for clotrimazol e varied fi-om 0,1 to 1,56 mu g/ml in almost all strains. Higher value s were obtained for T. rubrum (12,5 mu g/ml) and T. mentagrophytes (25 ,0 mu g/ml). Cetoconazole was the imidazole drug that showed the highe st MIC and MFC values, as high as 100,0 mu g/ml when tested against th e species of T. rubrum, T. mentagrophytes, T. tonsurans aid M. gypseum . The antifungal activities of the other imidazole drugs were comparab le, the MIC and MFC values varied from 0,10 to 12.5 mu g/ml. In relati on to griseofulvin, the fungi used in this study, presented two differ ent behaviours: higher MIC and MFC values (12,5 to 100,0 mu g/ml) for T. rubrum, T. mentagrophytes, T. tonsurans, T. soudanense, M. canis, M . gypseum and M. persicolor and lower values (0,39 to 3,12 mu g/ml) fo r T. schoenleinii, T. violaceum, E. floccosum, and M. audouinii. E. fl occosum, M. canis and T. schoenleinii had higher susceptibilitis to th e drugs, (MIC and MFC values varying from 0,05 to 0,20 mu g/ml), when compared to T. mentagrophytes, T. rubrum, M. gypseum and T. soudanense . No important differences were observed in tile MIC aid MFC values fo r. tile ''wild'' and the ''collection'' strains.