Invasive Infections Due to <i>Trichosporon</i> : Species Distribution, Genotyping, and Antifungal Susceptibilities from a Multicenter Study in China

Abstract

A total of 133 clinical <i>Trichosporon</i> isolates were collected in the National China Hospital Invasive Fungal Surveillance Net (CHIF-NET) program in 2009 to 2016. Accurate identification was performed by sequencing of the intergenic spacer 1 (IGS1) region. Among these isolates, <i>Trichosporon asahii</i> (108 isolates [81.2%]) was the leading species, followed by <i>Trichosporon dermatis</i> (7 isolates [5.3%]), <i>Trichosporon asteroides</i> (5 isolates [3.8%]), <i>Trichosporon inkin</i> (5 isolates [3.8%]), <i>Trichosporon dohaense</i> (3 isolates [2.3%]), and 1 isolate (0.7%) each of <i>Trichosporon faecale</i>, <i>Trichosporon jirovecii</i>, <i>Trichosporon mucoides</i>, <i>Trichosporon coremiiforme</i>, and <i>Trichosporon montevideense</i> Both the Vitek mass spectrometry (MS) (bioMérieux, Marcy l'Etoile, France) and Bruker Biotyper MS (Bruker Daltonics GmbH, Germany) platforms gave high levels (>97.5%) of correct identification when the species were present in the database. The geometric mean (GM) of amphotericin B MICs for <i>T. asahii</i> was 2-fold higher than that for non-<i>asahii Trichosporon</i> High fluconazole MICs (≥8 μg/ml) were observed for 25% of <i>T. asahii</i> isolates (27/108 isolates) and 16% of non-<i>asahii Trichosporon</i> (4/25 isolates) isolates. Itraconazole MICs were ≤0.5 μg/ml for 89.5% of the isolates. Voriconazole was the most potent antifungal agent <i>in vitro</i>, with a GM of 0.09 μg/ml. Genotyping of the isolates using IGS1 sequence alignment revealed that genotype 1 was most common (41.7%), followed by genotype 4 (31.5%), genotype 3 (23.1%), genotype 5 (0.9%), genotype 6 (0.9%), and genotype 7 (1.8%). Our data on species distribution, genotypes, and antifungal susceptibilities may contribute to a better understanding of the epidemiology of invasive <i>Trichosporon</i> infections throughout China.