Suitability of the modified API 20 C, Mycotube and Bacto-Candida-albicans-Antiserum for the identification of yeasts in the routine laboratory.

In a clinical routine study 304 yeasts were examined with the aid of API 20 C Auxanogram (Analytab Products Inc.) Mycotube (Roche) and Bacto-Candida-albicans-Antiserum (Difco) (=CAA). API (in parenthesis the result of the Mycotube test) identified 99% (92.4%) correctly; without considering C. albicans, the result was correct in 96.5% (75.8%). The CAA indicated a high specificity against C. albicans. For the Routine Laboratory we recommend screening of all yeasts with the CAA; an additional morphological examination is also recommended as cross-reactions with C.tropicalis and Torulopsis species are found. The non-agglutinating yeasts can then be further examined with the API 20 C.