厚皮马拉色菌引起面部疣状增生性结节一例

目的 报道1例由厚皮马拉色菌引起的面部疣状增生性结节。方法 采用真菌直接镜检与培养、温度试验、过氧化氢酶试验、皮肤病理检查、PAS染色和扫描电镜对1例面部疣状增生性结节女性患者分离出的菌株进行鉴定。结果 皮损病理检查显示真皮内慢性炎症细胞弥漫性浸润,PAS染色见真皮内散在的孢子。皮损和宠物狗皮屑革兰氏染色,镜检发现大量革兰氏阳性酵母样孢子及芽孢。含橄榄油及不含油SDA 27℃培养2周,见乳白色酵母样菌落生长。该菌在含油SDA培养,27℃生长最佳;过氧化氢酶试验阴性。扫描电镜观察显示菌体较小,芽颈较宽,基围较厚,孢子呈球形、卵圆形、椭圆形等形态。上述结果提示该菌为厚皮马拉色菌。结论 厚皮马拉色菌引起面部疣状增生性结节为国内首例报道,氟康唑联合局部冷冻治疗获得良好疗效。

A case of facial verrucous proliferating nodules caused by Malassezia pachydermatis

Objective To report a case of facial verrucous proliferating nodules caused by Malassezia pachydermatis.Methods Direct microscopic examination,fungal culture,temperature test,catalase test,pathological examination,PAS staining,and scanning electron microscopy were used to identify the fungus isolated from a woman with facial verrucous proliferating nodules.Results Pathological examination with HE and PAS staining of the lesion showed diffuse infiltration of chronic inflammatory cells and sparse distribution of spores in the dermis.Microscopically,Gram staining of lesional secretions and pet dog scales showed many yeast-like spores and germs.After culture of the lesion specimen at 27℃ for 2 weeks, yeast-like milky colonies apppeared on Sabouraud's agar (SDA) medium with/without olive oil.The fungus grew well on SDA medium with olive oil at 27℃,and was catalase-negative.The ultrastructural examination of the fungus under a scanning electon microscope showed small cells,broad budding collarette,thick budding base,and spherical,oval or ellipse spores,etc.The above-mentioned characteristics suggested that the fungus was Malassezia pachydermatis.Conclusion It is the first case report of facial verrucous proliferating nodules due to Malassezia pachydermatis transmitted by pet dogs in China,and fluconazole plus lesional freezing has good therapeutic effects.