A Case of Subcutaneous Phaeohyphomycosis Caused by Exophiala xenobiotica in a Poorly-Controlled Diabetic Patient: The Conventional Papanicolaou Staining on Cytology Specimen Can Potentially Guide Us to the Correct Diagnosis

IF 1 4区医学 Q4 MEDICAL LABORATORY TECHNOLOGY

Diagnostic Cytopathology Pub Date : 2025-01-27 DOI:10.1002/dc.25444

Rie Kadoguchi, Kazushi Anzawa, Yoshiiku Okanemasa, Yao Liu, Vu Anh Dung, Akihiro Shioya, Sohsuke Yamada

{"title":"A Case of Subcutaneous Phaeohyphomycosis Caused by Exophiala xenobiotica in a Poorly-Controlled Diabetic Patient: The Conventional Papanicolaou Staining on Cytology Specimen Can Potentially Guide Us to the Correct Diagnosis","authors":"Rie Kadoguchi, Kazushi Anzawa, Yoshiiku Okanemasa, Yao Liu, Vu Anh Dung, Akihiro Shioya, Sohsuke Yamada","doi":"10.1002/dc.25444","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <h3> Background</h3>\n \n <p>Phaeohyphomycosis is a very rare fungal infection, which is one of more usual complications in immunocompromised and/or traumatic patients, has never been reported especially in a cytological field. We describe a first case of subcutaneous phaeohyphomycosis caused by <i>Exophiala xenobiotica</i> (<i>E. xenobiotica</i>) in a poorly controlled diabetic patient, and in which a correct cytological diagnosis of phaeohyphomycosis was possible to conclude.</p>\n </section>\n \n <section>\n \n <h3> Case Presentation</h3>\n \n <p>The diabetic obese patient was a 60's-year-old male with a chief complaint of subcutaneous cyst-like nodule on the left knee. The Papanicolaou staining on aspiration cytology from this central fluid contained a substantial number of characteristically brown hyphae with dichotomous branching conidiophores and annelloconidia formation, in the necrotic and inflammatory backgrounds. Culture on potato dextrose agar showed many slow-growing yeast-like colonies particularly in an olivaceous gray to black colored fashion. Furthermore, sequencing data for the rRNA internal transcribed spacer (ITS) regions confirmed phaeohyphomycosis caused by <i>E. xenobiotica</i> infection. Histologically, the resected subcutaneous nodule was diagnosed as necrotizing epithelioid granulomas with central abscess formation, admixed with a large number of dichotomous branching fungal organisms with conidia, reminiscent of <i>Aspergillus</i>. However, Fontana-Masson staining readily identified the melanin pigments in these fungal hyphae.</p>\n </section>\n \n <section>\n \n <h3> Conclusion</h3>\n \n <p>In this subcutaneous cyst-like case of immunocompromised patient, it is critical to consider the possibility of subcutaneous phaeohyphomycosis. The conventional methodology of Papanicolaou staining on cytology specimen can recognize characteristically typical dichotomous branching and brown-pigmented fungi, potentially guiding us to the correct and quick diagnosis.</p>\n </section>\n </div>","PeriodicalId":11349,"journal":{"name":"Diagnostic Cytopathology","volume":"53 4","pages":"E70-E74"},"PeriodicalIF":1.0000,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Diagnostic Cytopathology","FirstCategoryId":"3","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/dc.25444","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MEDICAL LABORATORY TECHNOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

Background

Phaeohyphomycosis is a very rare fungal infection, which is one of more usual complications in immunocompromised and/or traumatic patients, has never been reported especially in a cytological field. We describe a first case of subcutaneous phaeohyphomycosis caused by Exophiala xenobiotica (E. xenobiotica) in a poorly controlled diabetic patient, and in which a correct cytological diagnosis of phaeohyphomycosis was possible to conclude.

Case Presentation

The diabetic obese patient was a 60's-year-old male with a chief complaint of subcutaneous cyst-like nodule on the left knee. The Papanicolaou staining on aspiration cytology from this central fluid contained a substantial number of characteristically brown hyphae with dichotomous branching conidiophores and annelloconidia formation, in the necrotic and inflammatory backgrounds. Culture on potato dextrose agar showed many slow-growing yeast-like colonies particularly in an olivaceous gray to black colored fashion. Furthermore, sequencing data for the rRNA internal transcribed spacer (ITS) regions confirmed phaeohyphomycosis caused by E. xenobiotica infection. Histologically, the resected subcutaneous nodule was diagnosed as necrotizing epithelioid granulomas with central abscess formation, admixed with a large number of dichotomous branching fungal organisms with conidia, reminiscent of Aspergillus. However, Fontana-Masson staining readily identified the melanin pigments in these fungal hyphae.

Conclusion

In this subcutaneous cyst-like case of immunocompromised patient, it is critical to consider the possibility of subcutaneous phaeohyphomycosis. The conventional methodology of Papanicolaou staining on cytology specimen can recognize characteristically typical dichotomous branching and brown-pigmented fungi, potentially guiding us to the correct and quick diagnosis.

查看原文本刊更多论文

1例控制不良的糖尿病患者由外生菌引起的皮下褐丝酵菌病：细胞学标本的常规巴氏染色可能指导我们正确诊断。

背景：褐丝酵母菌病是一种非常罕见的真菌感染，是免疫功能低下和/或创伤患者的常见并发症之一，从未在细胞学领域报道过。我们描述了第一例由外生菌（E. xenobiotica）引起的皮下褐丝酵母菌病在一个控制不良的糖尿病患者，并在其中一个正确的细胞学诊断的褐丝酵母菌病是可能的结论。病例介绍：60岁男性糖尿病肥胖患者，主诉为左膝皮下囊肿样结节。该中心液滴吸细胞学的Papanicolaou染色在坏死和炎症背景中含有大量具有分支分生孢子和环状分生孢子形成的特征性棕色菌丝。在马铃薯葡萄糖琼脂上培养显示出许多生长缓慢的酵母样菌落，特别是橄榄色的灰色到黑色。此外，rRNA内部转录间隔区（ITS）的测序数据证实了由E. xenobiotica感染引起的褐丝酵母菌病。组织学上，切除的皮下结节被诊断为坏死性上皮样肉芽肿伴中央脓肿形成，并伴有大量分生孢子的分叉真菌生物，使人联想到曲霉。然而，Fontana-Masson染色很容易识别出这些真菌菌丝中的黑色素。结论：在这例免疫功能低下的皮下囊肿样病例中，考虑皮下褐丝酵菌病的可能性至关重要。传统的细胞学标本Papanicolaou染色方法可以识别出典型的二分分支和棕色真菌，有可能指导我们正确和快速的诊断。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Diagnostic Cytopathology 医学-病理学

CiteScore

2.60

自引率

7.70%

发文量

163

审稿时长

3-6 weeks

期刊介绍： Diagnostic Cytopathology is intended to provide a forum for the exchange of information in the field of cytopathology, with special emphasis on the practical, clinical aspects of the discipline. The editors invite original scientific articles, as well as special review articles, feature articles, and letters to the editor, from laboratory professionals engaged in the practice of cytopathology. Manuscripts are accepted for publication on the basis of scientific merit, practical significance, and suitability for publication in a journal dedicated to this discipline. Original articles can be considered only with the understanding that they have never been published before and that they have not been submitted for simultaneous review to another publication.