Present status of the detection of antifungal resistance: the perspective from both sides of the ocean

The NCCLS reference methodology for antifungal susceptibility testing is a new milestone of the evolution of medical mycology. The use of this methodo logy however, is not problem-free. At present, major limitations are a trai ling phenomenon with azoles. unreliable detection of resistance to amphoter icin B, poor growth of some organisms and unpractical procedures for the cl inical laboratory. Herein a overview of NCCLS guidelines for yeasts and fil amentous fungi is presented. Likewise. a review of studies conducted trying to overcome the limitations of reference procedures is also included. Seve ral alternative approaches are reviewed as alternative media. inoculum size and incubation time. Modifications of reading procedure and endpoint deter mination are also evaluated. Agar diffusion methods and other methods for s usceptibility testing are cited. Finally, we discuss the data on correlatio n of the in vitro results with the in vivo activity.