Trichosporon dohaense , a rare pathogen of human invasive infections, and literature review

is a rare fungal species that has not been described in human invasive infections. In this study, we investigated two isolates from patients with invasive infections in two hospitals in China, as part of the China Hospital Invasive Fungal Surveillance Net (CHIF-NET) program. Both patients were under immunocompromised conditions. On chromogenic agar, isolates were dark blue, similar to the color of , but the characteristic moist colony appearance was quite different from that of . The two isolates were misidentified as and by the VITEK 2 YST system. The rDNA internal transcribed spacer (ITS) region and the D1/D2 domain sequences of the two isolates were 100% identical to type strain CBS10761 . The sequence of the intergenic spacer region-1 also clearly distinguished the species. Of the three matrix-assisted laser desorption/ionization time-of-flight mass spectrometry systems, Bruker Biotyper and Autobio MS correctly identified the two isolates to species level, whereas Vitek MS systems misidentified them as or . Echinocandins exhibited no in vitro activities against the two isolates. In addition, the isolates exhibited intermediate susceptibility to fluconazole (with minimal inhibitory concentrations [MICs] of 8 and 16 µg/mL) and itraconazole, voriconazole, and posaconazole (MICs of 0.25-1 µg/mL). demonstrated susceptibility to amphotericin B with MIC of 1 µg/mL. The MICs of fluconazole and voriconazole in our study were higher than the MIC of 62 for isolates (4 and 0.064 µg/mL) in the CHIF-NET program. This case study points to a possible emergence of as an opportunistic human invasive fungal pathogen, and the reduced susceptibility should be noted.