Application of agglutinins for the rapid and accurate identification of medically important Candida species.

Agglutinins have been prepared against the medically important Candida species. Crude antisera to the various species demonstrated intense cross-reactions with heterologous yeastlike fungi as well as with many true yeasts. However, carefully monitored adsorptions of selected antisera allowed the production of six factor sera that proved useful in a slide agglutination test. These six sera permitted the rapid and specific identification of C. guilliermondii, C. krusei, C. parapsilosis, and C. pseudotropicalis. They also allowed the delineation of two groups: (i) C. albicans (type A)-C. tropicalis and (ii) C. albicans (type B)-C. stellatoidea. C. albicans type A could be readily distinguished from C. tropicalis by its ability to form germ tubes in serum. C. stellatoidea could be distinguished from C. albicans type B by its predominantly filamentous growth on a nutritionally deficient medium. The medically important Candida species could be identified within 24 hr by the combined use of serological and morphological procedures.