STANDARDIZATION OF ANTIFUNGAL SUSCEPTIBILITY TESTING AND CLINICAL RELEVANCE

Standardization of antifungal susceptibility testing became essential to overcome the problem of interlaboratory variability and to determin e the clinical relevance of in vitro data. This evolving process began for the yeasts and consequently broth macrodilution and microdilution methods (NCCLS M27 document) have been developed. These tests may not be useful for testing all organism-drug combinations or be the most c onvenient techniques for routine use in the clinical laboratory. Diffe rent alternatives to the NCCLS methods are currently under investigati on. The identification of standard guidelines for antifungal susceptib ility testing has reduced interlaboratory variability and further prog ress has been achieved with the determination of tentative interpretiv e breakpoints for certain drug-yeast combinations. However, these brea kpoints are not adequate for interpretations of MICs for fungi-drug co mbinations beyond the setting for which they were determined. The NCCL S Subcommittee has also generated data for proposed testing guidelines for the moulds.