Wongsuk Thanwa, Boonsilp Siriphan, Pumeesat Potjaman, Homkaew Anchalee, Sangsri Tanes, Chongtrakool Piriyaporn
1Department of Clinical Pathology, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Bangkok, Thailand.
2Department of Medical Technology, Faculty of Science and Technology, Bansomdejchaopraya Rajabhat University, Bangkok, Thailand.
Acta Microbiol Immunol Hung. 2022 Aug 16;69(3):247-257. doi: 10.1556/030.2022.01797. Print 2022 Sep 16.
The basidiomycetes yeast Trichosporon is widespread in the natural environment, but can cause disease, mainly in immunocompromised patients. However, there have been only few studies about this infection in Thailand. In this study, we characterized 53 Trichosporon spp. isolated from urine samples from patients admitted to a single hospital in Bangkok, Thailand over a one-year period from 2019 to 2020. The strains were identified using colony morphology, microscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and nucleotide sequence analysis of intergenic spacer 1 (IGS1). Fifty-one isolates were Trichosporon asahii, and the remaining isolates were Trichosporon inkin and other Trichosporon species. Three genotypes of IGS1-1, 3, and 7 were observed among T. asahii. The sensitivity of the yeasts to the antifungal drugs amphotericin B, fluconazole, and voriconazole ranged from 0.25 to >16 μg ml-1, 0.5-8 μg ml-1, and 0.01-0.25 μg ml-1, respectively. We investigated biofilm formation by the isolates, and no biofilm production was found in one isolate, low biofilm production in forty-four isolates, and medium biofilm production in six isolates. T. inkin produced biofilms at low levels, and Trichosporon spp. produced biofilms at medium levels. This research increases our understanding of the molecular epidemiology of Trichosporon spp. isolated from one university hospital in Bangkok, Thailand, and reveals their genetic diversity, antifungal susceptibility profiles, and capacity for in vitro biofilm production.
担子菌酵母毛孢子菌在自然环境中广泛存在，但可引发疾病，主要发生在免疫功能低下的患者中。然而，泰国关于这种感染的研究很少。在本研究中，我们对2019年至2020年期间从泰国曼谷一家医院收治的患者尿液样本中分离出的53株毛孢子菌属菌株进行了特征分析。使用菌落形态、显微镜检查、基质辅助激光解吸/电离飞行时间质谱以及基因间隔区1（IGS1）的核苷酸序列分析对菌株进行鉴定。51株分离株为阿萨希毛孢子菌，其余分离株为因金毛孢子菌和其他毛孢子菌属物种。在阿萨希毛孢子菌中观察到IGS1的三种基因型，即1、3和7型。这些酵母对两性霉素B、氟康唑和伏立康唑的敏感性范围分别为0.25至>16 μg/ml、0.5至8 μg/ml和0.01至0.25 μg/ml。我们研究了分离株的生物膜形成情况，发现一株分离株未产生生物膜，44株分离株生物膜产生水平低，6株分离株生物膜产生水平中等。因金毛孢子菌生物膜产生水平低，毛孢子菌属物种生物膜产生水平中等。本研究增进了我们对从泰国曼谷一家大学医院分离出的毛孢子菌属菌株分子流行病学的了解，并揭示了它们的遗传多样性、抗真菌药敏谱以及体外生物膜产生能力。
