Biochemical differentiation of the etiologic agents of chromoblastomycosis from non-pathogenic Cladosporium species.

respectively. These pathogens are separated from closely related saprophytic Cladosporium species on the basis of their gross and microscopic morphology. However, the general appearance of the colonies of both the pathogenic and saprophytic members of this group is quite similar. In general, the saprophytic species grow more rapidly than the pathogens, but rate of growth is of dubious value in identification which is influenced by many factors. The saprophytic Clad osporium species produce spores by only one type of sporulation designated as the "cladosporium type". The pathogenic species in this group also have the "cladosporium type" but in addition they possess other types of sporulation. Due to their absence in some isolates or irregularity of production these other types of sporulation cannot be utilized to identify some isolates. Biochemical studies by Montemayor (1), De Yries (2) and Trejos (3) led us to make a study of the biochemical activities of this group of organisms in the hope of finding a method independent of morphologic structures for differentiating between pathogenic dematiaceous fungi and morphologically similar saprophytic species.