阿萨希毛孢子菌与西弗射盾子囊霉的实验室鉴定与体外抗真菌药敏特点分析  

Laboratory identification and in vitro analysis of antifungal susceptibility of Trichosporon asahii and Stephanoascus ciferrii

作　　者：林思佳 袁凯旋 LIN Sijia;YUAN Kaixuan(Department of Laboratory Medicine,Chaozhou People's Hospital,Chaozhou 512000,China;Department of Laboratory Medicine,Guangdong Provincial People's Hospital,Southern Medical University,Guangzhou 510000,China)

机构地区：[1]潮州市人民医院检验科,潮州521000 [2]南方医科大学附属广东省人民医院检验科,广州510080

出　　处：《中国真菌学杂志》2024年第2期143-149,153,共8页Chinese Journal of Mycology

摘　　要：目的探讨阿萨希毛孢子菌与西弗射盾子囊霉的实验室鉴定与体外抗真菌药敏特点,为临床用药、准确鉴定和流行病学研究提供依据。方法收集2017年1月—2022年9月广东省人民医院临床分离的2种少见酵母样真菌,其中阿萨希毛孢子菌54株,西弗射盾子囊霉23株,复苏后进行形态学鉴定、生化鉴定和质谱鉴定,同时采用FUNGUS-3 MIC法测定5-氟胞嘧啶、两性霉素B、氟康唑、伊曲康唑和伏立康唑的最小抑菌浓度(MIC)。结果阿萨希毛孢子菌主要感染65岁以上人群(46.30%),感染部位以创面感染(27.78%)与尿路感染为主(22.22%),主要分布于外科(35.19%)和内科(35.19%);而西弗射盾子囊霉感染患者主要以18~40岁(39.13%)和41~65岁(47.83%)两个年龄段为主,感染部位以耳道为主(78.26%),分布于耳鼻喉外科病区(60.87%)和耳聋专科门诊(26.09%);在形态学鉴定方面,2种真菌菌落均为白色凸起,呈镶嵌生长,其中阿萨希毛孢子菌生长速度快于西弗射盾子囊霉,菌落革兰染色可见关节孢子、关节菌丝、真假菌丝及芽生孢子,而西弗射盾子囊霉可见分枝分隔菌丝和单细胞、卵圆形的芽生孢子。在生化鉴定方面,阿萨希毛孢子菌尿素酶阳性,可水解七叶苷,同化多种糖类化合物,而西弗射盾子囊霉尿素酶阴性、不水解七叶苷,但可同化多种碳水化合物。微生物质谱对阿萨希毛孢子菌和西弗射盾子囊霉的鉴定率分别为96.30%和91.30%,具有良好鉴定效果;在体外药敏结果方面,两种真菌对5-氟胞嘧啶均表现出高MIC值,其中54株(100%)阿萨希毛孢子菌MIC值均≥4μg/mL,23株(100%)西弗射盾子囊霉MIC值均≥4μg/mL;同时也需警惕2种真菌对氟康唑出现高MIC值的情况,其中7株(12.97%)阿萨希毛孢子菌MIC值均≥4μg/mL,16株(69.56%)西弗念珠菌MIC值≥16μg/mL;两性霉素B、伊曲康唑、伏立康唑则整体上表现出较低的MIC值(≤2μg/mL),表现出较好的体外活性。结论阿萨Objective To investigate the laboratory identification and in vitro antifungal susceptibility of T.asahii and S.ciferrii,so as to provide evidence for clinical treatment,laboratory identification and epidemiological study.Methods Two rare yeast-like fungi were collected from Guangdong Provincial People's Hospital from January 2017 to September 2022,54 strains of T.asahii and 23 strains of S.ciferrii were revived and identified by morphology,physiology,biochemistry,and MALDI-TOF MS.The minimum inhibitory concentrations of 5-flucytosine,amphotericin B,fluconazole,itraconazole and voriconazole to all strains were tested by FUNGUS-3 MIC method.Results T.asahii mainly infected people aged above 65 years old(46.30%),with wound area(27.78%)and urinary tract(22.22%)being the main sites of infection.These patients are mainly distributed in surgery(35.19%)and medicine(35.19%).However,The patients with S.ciferrii infection were mainly aged 18-40 years old(39.13%)and 41-65 years old(47.83%).The infection site was mainly in the ear canal(78.26%),which was distributed in the otorhinolaryngological surgery area(60.87%)and the otorhinolaryngological clinic(26.09%).In terms of morphological identification,both fungi were white raised colonies,embedded on the surface of the medium,T.asahii growth faster than S.ciferrii.After Gram staining of T.asahii,arthrospore,articular hyphae,euhyphae,pseudohyphae and blastospore were observed under microscope.In contrast,in S.ciferrii,branching septate hyphae and unicellular,oval blastophores were seen.In terms of biochemical identification,T.asahii urease was positive and could hydrolyze heptagenin,assimilating multiple carbohydrate compounds,while S.ciferrii urease was negative and does not hydrolyze heptagenin,but could assimilate multiple carbohydrates.In terms of mass spectrometry identification,the identification rates of T.asahii and S.ciferrii were 96.30%and 91.30%,respectively,with good identification results.In vitro susceptibility results of both fungi showed high MIC values to 5-fl

关 键 词：阿萨希毛孢子菌 西弗射盾子囊霉 实验室鉴定 抗真菌体外药物敏感性试验 

分 类 号：R379.9[医药卫生—病原生物学]