Fonsecaea monophora所致着色芽生菌病1例及其相关实验研究

目的 报道1例由Fonsecaea monophora所致的着色芽生菌病.方法 患者女,60岁,主因左手背皮损1 a余就诊,取皮损痂屑进行真菌直接镜检和培养,取皮损组织进行组织病理学检查和真菌培养.对培养获得菌株进行形态学和分子生物学鉴定,并进行药物敏感性检测.结果 真菌直接镜检阳性,可见较多圆形、厚壁、棕色的硬壳细胞.组织病理学显示为慢性肉芽肿样改变;HE和PAS染色均可见到圆形、厚壁、棕色的硬壳细胞.真菌培养阳性,菌落生长缓慢,呈橄榄色到黑色.小培养及扫描电镜检查可见枝孢型和喙枝孢型产孢,分生孢子单细胞性,呈椭圆形或卵圆形.ITS区序列分析鉴定为Fonsecaea monophora.药敏试验显示伊曲康唑对F.monophora的最低抑菌浓度（minimal inhibitory concentration,MIC）为1.0 μg/mL,特比萘芬的MIC为0.015 6μg/mL.给予患者口服特比萘芬250 mg/d治疗,皮损缓慢好转;6周后加服伊曲康唑200 mg/d治疗,14周后皮损消退呈瘢痕化修复.结论 依据临床及实验室检查确诊该病例为Fonsecaeamonophora所致着色芽生菌病,伊曲康唑联合特比萘芬治疗本病例显示较好疗效.

A case of cutaneous chromoblastomycosis caused by Fonsecaea monophora and laboratory study

Objective To report a case of chromoblastomycosis caused by Fonsecaea monophora and related laboratory investigation.Methods A 60-year-old woman was admitted with skin granulomatous lesions on the left hand for more than one year.Direct smear examination and fungal culture,Histopathologic examination,scanning electron microscope examination,PCR and ribosomal internal transcribed spacer（ITS） sequence analysis were performed for diagnosis.The antifungals susceptibility was tested according to M38-A2 published by CLSI.Results Sclerotic bodies were observed by direct smear examination.Histopat hologic examination showed chronic granuloma and round,thick-walled sclerotic bodies.Fungal cuhure produced olivaceous to black colonies.Rhinocladiella type and cladosporium type conidia were observed in the slide culture and scanning electron microscope examination.Ribosomal DNA ITS domains were amplified,and the product was sequenced,which was aligned with 100％ sequential similarity to multiple sequences of F.monophora in the GenBank database.The MICs for itraconazole and terbinafine were 1.0 μg/mL and 0.015 6 μg/mL against this strain,After treatment with terbinafine （250 mg,QD） alone for 6 weeks,and itraconazole （200 mg,QD） combined with terbinafine （250 mg,QD）for 8 weeks,the patient was cured.Conclusions The case of cutaneous chromoblagtomycosis was caused by F.monophora identified by histopathology,mycology and molecular biology,Itraconazole with terbinafine has good effect.