Evaluation of a new system for the rapid identification of clinically important yeasts

Abstract

The rapid system developed by Huppert et al. (1975) for the identification of yeasts based on assimilation and fermentation patterns and on germ tube and pseudohyphal production was evaluated in a comparative study with conventional procedures. The 95 test cultures were members of the genera Candida, Cryptococcus, Rhodotorula, Saccharomyces, Torulopsis, and Trichosporon. The study revealed that approximately 94% of the isolates were correctly identified by the rapid method in comparison with the standard method. With the rapid method identification was accomplished in 72h, and with the conventional procedures identification was completed in 2 weeks. Although it was difficult with some isolates to obtain definitive speciation by the rapid method, this method promises to be especially useful in clinical laboratories for the identification of yeasts of medical importance. Modifications were made in the procedure of Huppert et al. (1975) to improve the reading of reactions. Commercial media and a disk dispenser to make the method more useful were also investigated.