熱帶念珠菌是主要引起院內念珠菌血症的致病菌之一，主要是感染免疫力低下的病人，特別是嗜中性白細胞低下的病人。熱帶念珠菌對於治療念珠菌血症的三唑藥物敏感度有下降的趨勢。對2011到2014年成大醫院從念珠菌血症中所分離的102株熱帶念珠菌的藥物敏感度進行回溯性研究。藥敏測試是利用先特真菌藥敏測試盤作分析，測試包含了9 種不同的抗真菌藥物。藥敏的結果顯示成大醫院的菌株對於三唑類藥物氟康唑(Fluconazole)和伏立康唑(Voriconazole)，抗藥率分別為20.6%和16.7%。利用多重序列分型（MLST）分析這些菌株的親源關係。從102株菌株當中發現56種不同的DST，當中有33種為新的DST。利用樹狀圖分析菌株之間的親源關係與對藥物敏感度的關聯性。結果顯示親源關係較相近的菌株對於伏立康唑表示出較接近的敏感度，氟康唑的敏感度與親源關係沒有表現出關聯性。同源複合物（clonal cluster）利用最小生成樹和eBURST去作分析，利用eBURST分析後共分成7組，結果顯示同屬同一組別對藥物表現出相似的敏感度。第7組內富含對三唑抗藥的菌株。本研究對於南台灣的熱帶念珠菌的藥物敏感度和多重基因序列分型有了進一步的了解。

Candida tropicalis is one of most important pathogens cause nosocomial candidemia and mainly cause infection in immunocompromised patients, especially in neutropenic patients. C. tropicalis show decrease the susceptible to candidemia therapy Triazole. A retrospective review of candidemia of C. tropicalis in National Cheng Kung University Hospital was conducted during 2011-2014. 102 isolates from blood cultures were enrolled in this study. The antifungal susceptibility determine by SensititreTM YeastOneTM with nine antifungal drugs. Antifungal susceptibility testing revealed that 20.6% were fluconazole resistance and 16.7% were voriconazole resistance. The genetic relatedness of 102 isolates were determined by Multilocus sequence typing (MLST). 56 different DSTs were identified in 102 isolates and 33 DSTs were new to database. The correlation between genetic relatedness and drug susceptibility was determine by UPGMA dendrogram. The result showed that genetic relatedness was more related to susceptibility of voriconazole than fluconazole. The clonal cluster was determined by Minimum Spanning tree and eBURST analysis which revealed 7 groups and the same eBURST group represent similar drug susceptibility. In addition, the triazole-resistance isolates were clustered in group 7. The present work extends the current understanding of antifungal susceptibility pattern and MLST typing of C. tropicalis in southern Taiwan.

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