A comparative evaluation of Etest and broth microdilution methods for fluconazole and itraconazole susceptibility testing of Candida spp.

The Etest strip is a promising tool of broad application in clinical microb iology. The method provides MIC readings and is easier to perform than brot h microdilution. We carried out a study to compare the MICs of fluconazole and itraconazole obtained by the Etest with those obtained by broth microdi lution, performed according to the guidelines of the NCCLS document M27-A, with 402 clinical isolates (360 Candida albicans, 17 Candida tropicalis, ni ne Candida krusei, nine Candida glabrata and seven Candida parapsilosis) an d seven control isolates. The agreement between MICs by the two methods (at +/- 2 dilutions) was 74.5% for fluconazole and 61.4% for itraconazole. The se results suggest that further development is necessary to standardize the medium and incubation conditions before introduction of the Etest as a rou tine method in the clinical microbiology laboratory for fluconazole and itr aconazole susceptibility testing.