Clinical comparison of the Baxter MicroScan Yeast Identification Panel and the Vitek Yeast Biochemical Card.

Abstract

To determine the reliability of the Baxter MicroScan Yeast Identification Panel, processed by the Walkaway-96, and the Vitek Yeast Biochemical Card, 150 clinical yeast isolates (30 Candida albicans, 67 Candida species, not albicans, 26 Torulopsis glabrata, 13 Cryptococcus neoformans, 4 Saccharomyces cerevisiae, 6 Trichosporon beigelii, 3 Rhodotorula species, and 1 Geotrichum species) were tested on both systems. Results were compared with those obtained by the API 20C and the appearance of yeast cells on cornmeal Tween-80 agar. After inoculation of each system, results were available in 4 hours with MicroScan panels, 24-48 hours with Vitek cards, and 72 hours with the API 20C strips. On initial testing, 101 (67%) and 128 (85%) isolates, respectively, were correctly identified by MicroScan and Vitek. After repeat testing, the number of correctly identified isolates increased to 123 (82%) by MicroScan and to 142 (95%) by Vitek. Yeasts most commonly misidentified were Candida tropicalis, T glabrata, and Candida parapsilosis by MicroScan and C tropicalis and T glabrata by Vitek.