Physiological typing of Pseudallescheria and Scedosporium strains using Taxa Profile, a semi-automated, 384-well microtitre system.

During the last few decades, Pseudallescheria and Scedosporium infections in humans are noted with increasing frequency. Multi-drug resistance commonly occurring in this species complex interferes with adequate therapy. Rapid and correct identification of clinical isolates is of paramount significance for optimal treatment in the early stages of infection, while strain typing is necessary for epidemiological purposes. In view of the development of physiological diagnostic parameters, 570 physiological reactions were evaluated using the Taxa Profile Micronaut system, a semi-automatic, computer-assisted, 384-well microtitre platform. Thirty two strains of the Pseudallescheria and Scedosporium complex were analysed after molecular verification of correct species attribution. Of the compounds tested, 254 proved to be polymorphic. Cluster analysis was performed with the Micronaut profile software, which is linked to the ntsypc® program. The systemic opportunist S. prolificans was unambiguously separated from the remaining species. Within the P. boydii/P. apiosperma complex differentiation was noted at the level of individual strains, but no unambiguous parameters for species recognition were revealed.