尖孢镰刀菌致坏疽性臁疮1例并文献复习

Ecthyma Gangrenosum Caused by Fusarium Oxysporum:A Case Report and Literature Review

目的分析真菌感染致坏疽性臁疮的临床特点、病理特点、病原菌种类、诊断及治疗方法。方法报告1例尖孢镰刀菌感染致坏疽性臁疮,并对1977-2015年真菌感染致坏疽性臁疮文献进行复习。结果患者男,17岁。右小腿胫前皮损3个月。取痂下坏死组织直接镜检见大量菌丝,真菌培养(SDA)见白色棉絮状菌落生长。扫描电镜观察见镰刀形大分生孢子。提取菌株DNA,对ITS,TEF-1α,BT2基因片段进行PCR扩增、测序、比对,鉴定为尖孢镰刀菌。予口服伊曲康唑治疗2周后,皮损稍好转,后失访。25例已报道病例中,男13例,女12例;年龄12d^69岁,中位年龄15岁。最常见基础疾病是血液系统恶性肿瘤(17例,占68.00%),包括急性白血病14例、淋巴瘤2例、多发性骨髓瘤1例。皮损部位:四肢或臀部23例(92.00%),躯干10例(40.00%),头面部4例(16.00%)。致病菌:镰刀菌7例(28.00%),毛霉目真菌7例(28.00%),念珠菌6例(24.00%),黑曲霉、双间柱顶孢、金龟子绿僵菌、弯孢菌和明脐霉各1例,分别占4.00%。21例(84.00%)予系统性抗真菌治疗,9例(36.00%)予外科治疗,包括外科清创术(4例)和手术切除局部皮损(5例)。15例(60.00%)治愈,1例(4.00%)好转,1例(4.00%)失访,8例(32.00%)死于本病,均为播散性感染。结论真菌感染致坏疽性臁疮主要发生于免疫受损患者,以白血病患者最多见,皮损好发于四肢或臀部,毛霉目真菌、镰刀菌和念珠菌是其最常见致病菌。播散性感染病死率高,及早诊断并合理治疗是治疗成功的关键。

Objective To analyze the clinical and histopathologic features, the pathogenic species, the diagnostic and therapeutic methods of Ecthyma gangrenosum Caused by Fungi.Methods We reported 1 case of ecthyma gangrenosum due to Fusarium oxysporum, and reviewed the literatures on Ecthyma gangrenosum Caused by Fungi published from 1977 to 2015.Results A 17-year-old male patient presented with skin lesion on his right lower leg for three months.Direct microscopic examination of necrotic tissue under crust demonstrated multiple hyphae and fungal culture on SDA yielded white cotton- like colony.Scanning electron microscopy showed sickle-shaped macroconidia.The pathogen was identified as Fusarium oxysporum by using polymerase chain reaction of fungal DNA followed by sequencing ITS,TEF-1α and BT2 genes.Slightly improvement was achieved after two-week treatment with itraconazole,and the patient did not return for follow up visits. Among 25 reported patients,13 were male and 12 females, with a median age of 15 years （range,12 days to 69 years）.Hematologic malignancies（17 cases[68.00%]）were the most common underlying disease, including 14 cases of acute leukemia,2 cases of lymphoma,1 cases of multiple myeloma.Distribution of skin lesions： limbs or buttocks（23 cases [92.00%]）, trunk（10 cases [40.00%]）, head and face（4 cases [16.00%]）.Pathogens：Fusarium（7 cases [28.00%]）,Mucorales（7 cases [28.00%]）,Candida（6 cases [24.00%]）,each of Aspergillus niger,Scytalidium dimidiatum,Metarhizium anisopliae Curvularia and Exserohilum（1 case [4.00%]）.21/25 cases（84.00%）received systemic antifungal therapy,and surgical treatment was used in 9 cases（36.00%）,including surgical debridement（4 cases） and surgical resection（5 cases）.Overall,15 patients（60.00%）were completely cured after treatment.Partial response was described for 1 patient（4.00%）.1 patient（4.00%）was lost to follow-up without receiving any treatment.8 patients（32.00%）died related directly to fungal infection and all of these patients＇infection type was disseminated infection.Conclusion Fungal Ecthyma gangrenosum is usually seen in immunocompromised patients, particularly those with leukemia.The skin lesions usually occur in the extremities or buttocks.Mucorales, Fusarium and Candida are the most frequent agents.Disseminated infection has a high mortality rate, so early diagnosis and reasonable treatment is the key to successful treatment.