Kinetik der minimalen Hemmkonzentration verschiedener Antimykotika gegenüber den klinisch isolierten Erregern der Onychomykosen während einer Beobachtungszeit von 20 Wochen

The aim of the investigations was to determine how long dermatophytes (Trichophyton rubrum and Trichophyton mentagrophytes) and molds (scopulariopsis brevicaulis) isolated from patients with a toenail mycosis can survive in sterile petry dishes, and whether such ex-vivo conditions may change the susceptibility of the fungi to antimycotics. Toe nails of 47 patients with onychomycosis were abraised with an electrical drill. The nail specimens were then stored in sterile petry dishes for 20 weeks at room temperature. Subsequently after nail abrasion, and 4, 8, 12, 16 and 20 weeks after abrasion, a part of the nail specimens were each cultured on 2 different mediums (Selective- and Standard agar). At week 20 all remained nail specimens were then cultured. Anytime a growth of fungi was observed the minimal inhibitory concentrations (MIC) of amorolfine, ciclopirox, fluconazole, itraconazole and terbinafine for isolated dermatophytes and molds were assessed by a microdilution test as described elsewhere 12 strains of T. rubrum , 5 strains of T. mentagrophytes and 9 strains of scopulariopsis brevicaulis were isolated from the toe nail of 47 patients with onychomycosis during 20 weeks. At week 20 a growth of T. rubrum (50%), T. mentagrophytes (40%) and scopulariopsis brevicaulis (77,8%) could still be proved . The MICs of ciclopirox (2-8 µg/ml), amorolfine (0,01-0,5 µg/ml) and terbinafine (0,005-5 µg/ml) seemed to be stable during the test period. By contrast, fluconazole (64-2048 µg/ml) and itraconazole (0,5-40 µg/ml) showed a broad range of the MICs. This could be explained by a limited reproducibility of the microdilution test for azole antimycotics. Against scopulariopsis brevicaulis fluconazole and itraconazole shows no activity. Some of dermatophytes (40-50%) and the most strains of scopulariopsis brevicaulis (77,8%) isolated from patients with toenail mycosis could survive in sterile petry dishes at least for a period of 20 weeks. These ex-vivo conditions do not seem to affect the susceptibility of the isolated dermatophytes to oral and topical antifungal agents. Each strain of T. rubrum, T. mentagrophytes and scopulariopsis brevicaulis showed during the test period an unchanged susceptibility to the antimycotics. The MICs observed agreed with previous findings of other groups.The aim of the investigations was to determine how long dermatophytes (Trichophyton rubrum and Trichophyton mentagrophytes) and molds (scopulariopsis brevicaulis) isolated from patients with a toenail mycosis can survive in sterile petry dishes, and whether such ex-vivo conditions may change the susceptibility of the fungi to antimycotics. Toe nails of 47 patients with onychomycosis were abraised with an electrical drill. The nail specimens were then stored in sterile petry dishes for 20 weeks at room temperature. Subsequently after nail abrasion, and 4, 8, 12, 16 and 20 weeks after abrasion, a part of the nail specimens were each cultured on 2 different mediums (Selective- and Standard agar). At week 20 all remained nail specimens were then cultured. Anytime a growth of fungi was observed the minimal inhibitory concentrations (MIC) of amorolfine, ciclopirox, fluconazole, itraconazole and terbinafine for isolated dermatophytes and molds were assessed by a microdilution test as described elsewhere 12 strains of T. rubrum , 5 strains of T. mentagrophytes and 9 strains of scopulariopsis brevicaulis were isolated from the toe nail of 47 patients with onychomycosis during 20 weeks. At week 20 a growth of T. rubrum (50%), T. mentagrophytes (40%) and scopulariopsis brevicaulis (77,8%) could still be proved . The MICs of ciclopirox (2-8 µg/ml), amorolfine (0,01-0,5 µg/ml) and terbinafine (0,005-5 µg/ml) seemed to be stable during the test period. By contrast, fluconazole (64-2048 µg/ml) and itraconazole (0,5-40 µg/ml) showed a broad range of the MICs. This could be explained by a limited reproducibility of the microdilution test for azole antimycotics. Against scopulariopsis brevicaulis fluconazole and itraconazole shows no activity. Some of dermatophytes (40-50%) and the most strains of scopulariopsis brevicaulis (77,8%) isolated from patients with toenail mycosis could survive in sterile petry dishes at least for a period of 20 weeks. These ex-vivo conditions do not seem to affect the susceptibility of the isolated dermatophytes to oral and topical antifungal agents. Each strain of T. rubrum, T. mentagrophytes and scopulariopsis brevicaulis showed during the test period an unchanged susceptibility to the antimycotics. The MICs observed agreed with previous findings of other groups.