[In vitro activity of a new semisynthetic echinocandin, micafungin, against clinical isolates of Candida species isolated in Tenri Hospital].

We have examined the antifungal activities of the available antifungal agents including micafungin (MCFG), one of the echinocandin antifungal group, against 92 yeast-like fungi isolated at our hospital during a 3-month period from November 2002 to February 2003. Determination of the antifungal susceptibility was conducted in conformity with the Standards of the Japanese Society for Medical Mycology. The MIC 80% of the antifungal agents against 4 fungi species including C. albicans (55 strains), C. tropicalis (20 strains), C. glabrata (8 strains), C. krusei (5 strains) were as follows; MCFG: 0.03-0.125 microgram/ml, amphotericin-B: 0.125-0.25 microgram/ml, 5-fluorocytosine: 0.125-16 micrograms/ml, itraconazole: 0.25-2 micrograms/ml, fluconazole: 0.5-32 micrograms/ml. The isolation rate of the drug-resistant fungi was 20% for the fluconazole (FLCZ)-resistant C. tropicalis and 33% when including the susceptible dose dependent (S-DD) class. The rate was 5% for FLCZ-resistant strains of C. albicans and 11% when including the S-DD class. However, MCFG was shown to have an excellent antifungal activity against those azole-resistant strains of Candida species. An analysis of the randomly amplified polymorphic DNA pattern (RAPD) was carried out to assess the fingerprinting of the azole-resistant strains. The results demonstrated a common pattern in 3 of the 6 strains of C. tropicalis that showed MIC of > or = 16 micrograms/ml for fluconazole, while all of the 6 strains of C. albicans demonstrated their respective patterns.