红色毛癣菌临床分离株的菌落形态和镜下结构特征再分析

目的探讨红色毛癣菌的菌落形态和镜下结构特征以及与感染部位的相关性。方法采用传统培养方法对192株红色毛癣菌进行表型分型,选取其中39株在28℃、30℃、35℃3种温度孵育6d、10d、14d时观察菌落形态和生长速度。结果192株红色毛癣菌共分离出3种表型：绒毛型、沟纹型、粉末型（或颗粒型）。在相同培养基上,28℃、30℃时菌落生长速度无显著差异（P〈0.05）,均快于35℃（P〈0.05）。在相同温度时,菌落在SDA上的生长速度快于PDA培养基。在28℃、30℃时菌落形态比较稳定,在35℃时变异较大。菌落在PDA培养基上产孢丰富,镜下显示有较多的大、小分生孢子,而在SDA培养基上只有少量的小分生孢子,几乎见不到大分生孢子。各种浅部感染均以绒毛型为主,绒毛型在手足癣中占比例最高,沟纹型在体股癣中所占比例较高,粉末型在甲癣中占的比例较高。结论红色毛癣菌的菌落形态与培养基和培养温度有关,其表型和镜下结构与感染部位均有一定的相关性。

Reanalysis of characteristics of colony morphology and microscopic structure of Trichophyton rubrum

Objective To study colony morphology and structural characteristics of Triehophyton rubrum under microscope and the relevance with sites of infection. Methods Traditional cultivation method was performed to discriminate the phenotypes of 192 strains of Trichophyton rubrum. Thirty nine strains of Trichophyton rubrum were cultured on Sabroud Dextrose Agar （SDA） and Potato Dextrose Agar （PDA） at 28℃ , 30℃and 35℃ respectively for two weeks. Colony morphology and growth rate were observed at 6,10,14 day. Results The colonies of 192 Triehophyton rubrum were classified into three types including downy type, furrowed type and powdery type. In the same medium, colony growth rate was not significantly different between 28℃ group and 30℃ group （ P 〉0.05）, both faster than that in 35℃ group （ P 〈0.05）. At same temperature, colony growth rate on SDA was faster than that on PDA. Strains cultured at 28℃ and 30℃ were found macrocopically stable, while varied at 35℃. Trichophyton rubrum strains on PDA sporlated more abundantly than that on SDA. More macroconidia and microconidia were observed, while few maeroeonidia was seen in SDA colonies. Downy type was the predominant phenotype in superficial infection and most common in tinea mannum and tinea pedis. Furrowed type was often seen in tinea cruris, while powdered type was common in onychomycosis. Conclusions Conoly morphology of Trichophyton rubrum was related with medium, culture temperature and sites of infection.