Abstract: Feng Yumiao, Wu Lijuan, Wang Miaomiao, Sun Lan, Zeng Xuesi, Shen Yongnian, Lyu Guixia, Liu Weida Department of Dermatology, Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou 215001, China （Feng YM, Wu LJ, Sun L）; Department of Dermatology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China （Wang MM）; Department of Pathology, Hospital of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China （Zeng XS）; Department of Mycology, Hospital of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China （Shen YN, Lyu GX, Liu WD） Corresponding author: Wang Miaomiao, Email: wangmiaomiao@suda.edu.cn 【Abstract】 A 55-year-old male patient presented with plaques on the face for more than 20 years, and no immunodeficiency diseases were diagnosed. Skin examination showed large areas of pink plaques on the nose, bilateral cheeks and upper oral lips with slight desquamation, verrucous hyperplasia on the dorsal area of the nose, and a bean-sized verrucous protuberance on the tip of the nose. Histopathological examination of the skin lesions revealed pseudoepitheliomatous hyperplasia in the epidermis and hyphae-like structures in the stratum corneum. Moreover, there was diffuse infiltration of inflammatory cells in the dermis, which mainly included neutrophils, lymphocytes, histiocytes and multinucleated giant cells. Periodic acid-Schiff （PAS）-positive spore-like structures were observed in the multinucleated giant cells. Culture of the lesional tissues on Sabouraud dextrose agar （SDA） medium showed grey-brown villous colonies. Microculture on the potato dextrose agar （PDA） medium yielded dark septate hyphae and pycnidia filled with a large number of spores. Microsphaeropsis arundinis was identified by fungal molecular biological techniques. The patient was diagnosed with cutaneous phaeohyphomycosis caused by Microsphaeropsis arundinis. The patient was treated with CO2 laser for the removal of verrucous protuberance on the tip of the nose, and oral itraconazole capsules at a dose of 200 mg twice a day. After 3-month treatment, the skin lesions subsided and the drug was withdrew. During 6-month follow-up, no relapse occurred.

Key words: Chromoblastomycosis, Sequence homology, nucleic acid, Face, Infection, Microsphaeropsis arundinis