CRITICAL ANALYSIS OF ANTIFUNGAL SUSCEPTIB ILITY TESTING

Yeast infections are an increasingly important problem and the recogni tion of antifungal resistance stresses the need for improved susceptib ility testing, Antifungal susceptibility testing has lacked reproducti bility because of the absence of universally accepted guidelines. The major sources of variation in susceptibility testing have been attribu ted to the choice of medium and pH, inoculum preparation and size, inc ubation temperature and time, and end-point criteria. These parameters have been addressed by the National Commmittee for Clinical Laborator y Standards (NCCLS) and proposed guidelines have recently been publish ed (M27-P). Although major advances in fungal susceptibility testing h ave been achieved, the results of studies to date do not support a cor relation between the results of in vitro susceptibility testing and in vivo response. Routine antifungal susceptibility testing of yeasts sh ould therefore be discouraged. Susceptibility testing of the filamento us fungi is currently poorly developed.