Fonsecaea monophora所致皮肤着色芽生菌病3例病原学鉴定及临床分析

Clinical Analysis of Three Cases Chromoblastomycosis and Identification of Fonsecaea Monophora

目的对3例Fonsecaea monophora所致皮肤着色芽生菌病进行病原学鉴定及临床分析。方法分析3例患者的临床特点。取患者皮损脓液直接镜检，皮损组织病理学检查及真菌培养。提取病原菌DNA，利用引物ITS4和ITS5进行rDNAITS区序列的PCR扩增，扩增产物测序后在GenBank核酸数据库及CBS数据库中进行同源性比对。结果皮损组织病理表现为慢性肉芽肿样改变，并可见硬壳小体。真菌培养可见暗棕色、橄榄色至黑色菌落生长，生长速度较慢，镜下可见枝孢型和喙枝孢型产孢。温度实验37℃生长，38℃不生长。0．01％，0．05％和0．1％放线菌酮均能耐受。经序列分析与GenBank及CBS数据库中Fonsecaea monophora的ITS区进行同源性比对，其同源性高。结合3例患者组织病理、真菌学特征及rDNAITS区序列分析将病原菌鉴定为Fonsecaea monophora。确诊后经口服伊曲康唑200mg，2次／d，6～8周后以200mg，1次／d维持治疗，或特比萘芬250mg，1次／d。治疗3个月后，皮损逐渐消退。结论Fonsecaea monophora与裴氏着色霉相似，可引起皮肤着色性芽生菌病，可通过分子生物学方法鉴别，口服伊曲康唑或特比萘芬治疗有效。

Objective To analyze the clinical features and identify the fnngal pathogen of three cases chromoblastomy- cosis infected by Fonsecaea monophora. Methods The clinical features of three chromoblastomycosis cases were analyzed. Their topathologic examination, direct smear examination and fungal culture were performed. PCR was used to amplify the DNA of the pathoden with primers ITS4 and ITS5. The amplified products were sequenced and blasted in GenBank for homology comparison. Results Histopathologic examination showed chronic granuloma and round, thick-walled sclerotic bodies. Fungal culture produced olivaceous to black colonies. Rhinocladiella type and cladosporium type conidia were observed in the slide culture. Maximum growth temperature was 37℃ and the isolate exhibited eycloheximide tolerant （0.01%, 0.05% and 0. 1% ）. Ribosomal DNA ITS domains were amplified, and the products were sequenced, which were high homology with F. monophora available in the GenBank and CBS database. The pathogenic fungi of three pa- tients were identified as Fonsecaea rnonophora by histopathology, pathogen identification and sequence analy- sis of ITS region. After treatment with itraconazole （ 200mg, BID for 6 - 8 weeks, then 200mg, QD ） or with terbinafine （250mg, QD） for 3 months, the patients＇ skin lesions gradually subsided. Conclusion Fonsecaea monophora was very similar to Fonsecaea pedrosoi,it may result in chromoblastomycosis, and rD- NA ITS sequence analysis is capable of idification of the pathogen . hraconazole and （or） terbinafine were effective on patients infected with Fonsecaea rnonophora.