The epidemiology, genotypes, antifungal susceptibility of Trichosporon species, and the impact of voriconazole on Trichosporon fungemia patients

Abstract

Invasive Trichosporon infections are emerging, but association of different therapeutic management of Trichosporon fungemia and clinical outcomes were rarely reported. This study investigates the epidemiology, species distribution and genotypes of trichosporonosis in Taiwan, and identified the predictors of clinical outcomes in patients with Trichosporon fungemia. Strains collected from four medical centers in Taiwan, during 2010-2018. Species identification was confirmed by sequencing of IGS1 region, and antifungal susceptibility was performed using Sensititre YeastOne panel. Among 115 isolates, Trichosporon asahii was the leading species (73.0%), followed by Trichosporon dermatis (11.3%), Trichosporon faecales (6.1%), and Trichosporon montevideense (5.2%). Of the 84 T. asahii isolates, genotype 1 was the predominant (41.7%). High fluconazole minimal inhibitory concentration (MICs,≧8μg/mL) were observed for 70.2% T. asahii isolates and 16.1% non-asahii Trichosporon isolates. Posaconazole and voriconazole possess the most potent antifungal activity against all Trichosporon isolates, with geometric mean values of 0.251μg/mL and 0.111μg/mL, respectively. Fifty-three isolates collected from blood cultures, and 42 patients with fungemia enrolled for the Kaplan-Meier plot which revealed that voriconazole treatment had a significantly better survival rate compared with those without (p=0.042). In multivariate analysis, source control (odds ratio [OR]: 0.13 95%CI [confidence interval]: 0.02-0.83, p=0.031) and voriconazole use (OR: 0.11 95%CI: 0.02-0.74, p=0.023) are independent predictors of 14-day mortality. This is the largest series of Trichosporon fungemia up till the present moment. Voriconazole therapy and source control play important roles in 14-day mortality.