Fransisca Cindy, He Ya, Chen Zhiwen, Liu Hongfang, Xi Liyan
Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
Med Mycol. 2017 Nov 1;55(8):851-858. doi: 10.1093/mmy/myw140.
Chromoblastomycosis is a chronic fungal infection of the skin and subcutaneous tissue. The most common etiologic agent encountered in Southern China is from the genus Fonsecaea. Fonsecaea species are often misidentified due to indistinct morphology features; furthermore, recent taxonomy revision was done on the fungi genus. Herein, a comprehensive evaluation with molecular sequencing data based on internal transcribed spacer (ITS) ribosomal DNA regions as molecular targets were implemented to 37 clinical isolates from chromoblastomycosis patients. Twenty strains that were formerly identified as Fonsecaea pedrosoi through morphological characteristic were verified to be either Fonsecaea nubica or Fonsecaea monophora, while 17 strains were appropriately identified as F. monophora. A phylogenetic method was further performed to establish the species delimitation. Our investigations validate that the clinical isolates from Guangdong consist of F. monophora and the recently found new species, F. nubica. In this study, F. pedrosoi has not been isolated from chromoblastomycosis patients in Guangdong, Southern China. Reevaluation of previous reports regarding F. pedrosoi as chromoblastomycosis etiologic agent in China is necessary for a comprehensive assessment of geographic distribution pattern of Fonsecaea species. This study is the first reported study presenting large samples of F. nubica domestic or abroad.
着色芽生菌病是一种皮肤和皮下组织的慢性真菌感染。在中国南方，最常见的病原体是瓶霉属真菌。由于形态特征不明显，瓶霉属真菌常被误认；此外，该真菌属最近进行了分类修订。在此，我们以核糖体DNA内转录间隔区（ITS）为分子靶点，对37株来自着色芽生菌病患者的临床分离株进行了基于分子测序数据的综合评估。通过形态学特征先前鉴定为裴氏瓶霉的20株菌株，经证实为努比亚瓶霉或单孢瓶霉，而17株菌株被正确鉴定为单孢瓶霉。进一步采用系统发育方法进行物种界定。我们的研究证实，来自广东的临床分离株包括单孢瓶霉和最近发现的新物种努比亚瓶霉。在本研究中，未从中国南方广东的着色芽生菌病患者中分离出裴氏瓶霉。有必要重新评估以往关于裴氏瓶霉作为中国着色芽生菌病病原体的报道，以便全面评估瓶霉属真菌的地理分布模式。本研究是国内外首次报道的关于大量努比亚瓶霉样本的研究。
