播散性阿萨希毛孢子菌病一例

A case report of disseminated trichosporonosis due to Trichosporon asahii

目的报道1例阿萨希毛孢子菌血症播散性消化系统及皮肤感染，探讨诊断和治疗方法。方法分析2年多的病史及其就诊的多家医院诊治资料。反复取多个部位溃疡坏死组织分别做组织病理检查，真菌学检查，取血、尿、粪行真菌培养，并作体外药物敏感试验，将培养菌落作rDNAITS序列测定。作腹部B超、肝胆核磁共振及逆行胰胆管造影（ERCP）等检查。及时联合应用足量的抗真菌药物系统治疗和局部治疗。结果病理检查发现坏死组织内大量成团孢子、少许菌丝、关节孢子及芽生孢子。坏死组织压片镜下发现大量菌丝、桶状关节孢子、芽生孢子。血液和多处溃疡组织培养均为阿萨希毛孢子菌生长。测序结果为阿萨希毛孢子菌。溃疡坏死组织及十二指肠乳头部炎性肉芽组织内均有菌丝、关节孢子。影像学检查及肝胆核磁共振及逆行胰胆管造影检查发现肝内外胆管炎、慢性胰腺炎、十二指肠乳头炎。确诊为阿萨希毛孢子菌血症——播散性毛孢子菌病。予两性霉素B和氟康唑联合治疗，后改为伊曲康唑治疗取得理想疗效。结论在诊断复杂的疑难病例时，特别是在按结核、结节病等久治无效反而加重时，应及时考虑深部真菌病。抗真菌药物应早期足量，随病情好转后渐渐减量，直至各部位炎症痊愈时才停药。

Objective To report a case of disseminated digestive tract and skin infection by Trichosporon asahii. Methods The patient＇s medical history, with the course of diagnosis and treatment at many hospitals over the past two years, was reviewed. Necrotic tissues were obtained fi＇om the ulcers at various body sites for direct microscopic examination, culture and histopathological examination. Fungus culture was performed with blood, urine, and stool samples. Antifungal susceptibility testing of the isolate was done in vitro. The sequence of rDNA ITS of the fungal isolate was tested. Type-B ultrasonic diagnosis, nuclear magnetic resonance for liver and gall, and endoscopic retrograde cholangiopan creatography （ERCP） were also performed. Sufficient antifungal agents were combined and applied timely for this patient systemically and topically. Results Pathological examination showed lumping spores, few hyphae, arthroconidia and blastospores in the necrotic tissues. As shown by direct microscopy of sheeting of necrotic tissues, there were abundant hyphae, tubby arthroconidia and blastospores. The culture of blood and many ulcer tissues was positive for the growth of Trichosporon asahii, which was proved to be sensitive to fluconazole and amphotericin B. Gene sequencing confirmed that the isolate was Trichosporon asahii. Abundant hyphae and arthroconidia were also found in the infectious granulomas of duodenum mamilla. Furthermore, angiocholitis of inner and outer liver, chronic pancreatitis and duodenal papillitis were detected by the above imaging examinations. A diagnosis of Trichosporon asahii fungemia-disseminated trichosporonosis was made. The patient was greatly improved by the combined treatment with fluconazole and amphotericin B followed by itraconazole. Conclusions Deep mycosis should be suspected in patients with a condition which could not be controlled or even exacerbated by the strategies of anti-tuberculosis, anti-sarcoidosis, etc. Antifungal agents should be applied sufficiently and early, and gradually decrease in dosage with disease improvement. Moreover, the treatment should maintain till the complete recovery.