Multicenter evaluation of ATB fungus: a standardized micromethod for yeast susceptibility testing

The micromethod for yeast susceptibility testing, ATB Fungus, was evaluated with 30 reference strains in three laboratories. Ready-to-use strips with 5-fluorocytosine, amphotericin B, nystatin, miconazole, econazole and ketoconazole were used. The test allowed the categorization of each strain as susceptible, intermediate or resistance to all the antifungals tested, and 5-fluorocytosine and amphotericin B MIC determination. The results were compared with the MIC for each reference strain obtained by a microdilution method on RPMI 1640 buffered with MOPS. The repeatability and intralaboratory and interlaboratory reproducibility were evaluated. ATB Fungus was a reliable and reproducible method with a repeatability of 96.6%, a reproducibility of 95.4% and showed an excellent correlation 91.7%) with reference MICs.