COMPARISON OF RAPID TESTING METHODS FOR ENZYME-PRODUCTION WITH THE GERM TUBE METHOD FOR PRESUMPTIVE IDENTIFICATION OF CANDIDA-ALBICANS

The observation of germ tube production as a method for the presumptiv e identification of Candida albicans has been in use for many years. M ethods have recently been developed for detecting the production of th e enzymes L-proline aminopeptidase and beta-galactosaminidase by yeast isolates grown in culture. Both enzymes are produced by C. albicans; other yeasts may produce either L-proline aminopeptidase or beta-galac tosaminidase but not both enzymes. One hundred thirty-three clinical y east isolates, including 55 C. albicans, 27 Candida tropicalis, 22 Tor ulopsis (Candida) glabrata, and 29 other yeast isolates were tested by the germ tube production method and three tests for enzyme production , with the API 20C method used as a ''gold standard.'' All three enzym atic methods evaluated provided more objective and rapid nonmicroscopi c alternatives to the germ tube test and may be used to accurately dis tinguish C. albicans from other yeasts.