Chromoblastomycosis: delayed diagnosis with extensive cutaneous lesions

•Chromoblastomycosis is a chronic cutaneous mycosis caused by pigmented fungi.•It is typically diagnosed late owing to polymorphous clinical appearance.•Prompt diagnosis can be made using 10% potassium hydroxide and biopsy preparations. Chromoblastomycosis (CBM) is a chronic cutaneous mycosis caused by the implantation of brown-pigmented fungi, primarily Fonsecaea species. It is a neglected tropical disease affecting impoverished populations in the tropics [[1]World Health OrganizationEnding the neglect to attain the sustainable development goals: a road map for neglected tropical diseases 2021–2030. World Health Organization, Geneva2020Google Scholar,[2]Elder DE et al.Atlas and synopsis of Lever's histopathology of the skin. Lippincott Williams & Wilkins, Philadelphia2012Google Scholar]. The clinical appearance of CBM is often polymorphic, with at least five different forms: nodular, tumoral, verrucous, plaque, and scarified; resulting in misdiagnosis or delayed diagnosis. A delayed diagnosis leads to chronic lymphedema, ankylosis, antifungal resistance, and in rare cases transformation into squamous cell carcinoma [[3]Belda Junior W Criado PR Casteleti P Passero LF. Chromoblastomycosis evolving to sarcomatoid squamous cell carcinoma: a case report.Dermatol Reports. 2021; 13: 9009https://doi.org/10.4081/dr.2021.9009Crossref PubMed Google Scholar,[4]Queiroz-Telles F de Hoog S Santos DW Salgado CG Vicente VA Bonifaz A et al.Chromoblastomycosis.Clin Microbiol Rev. 2017; 30: 233-276https://doi.org/10.1128/CMR.00032-16Crossref PubMed Scopus (170) Google Scholar]. Thus, early identification of the pathogens through direct microscopy, histopathological examination, or culture, as well as, more advanced molecular and serologic tests, is crucial [[5]Rimet Borges J Eda YV Ianhez M Garcíazapata MT Diagnosis of chromoblastomycosis: an historical review.Rev Patol Trop. 2022; 51: 97-115https://doi.org/10.5216/rpt.v51i2.71026Crossref Scopus (1) Google Scholar]. We described a 36-year-old barefooted farmer who was presented with an extensive itchy verrucous cutaneous lesion that had progressed from his left foot to the adjacent leg over the previous 8 years (Figure 1). An incisional biopsy (Figures 2a–c) and scrape samples for 10% potassium hydroxide preparation (Figure 3) were taken from the lesions and both revealed golden brown septated fungal spores variably described as, Medlar bodies, sclerotic bodies, or “copper pennies”.Figure 2Chromoblastomycosis: histopathologic features (hematoxylin and eosin stained section): low power field shows pseudoepitheliomatous hyperplasia with intraepidermal abscess (a) and numerous multinucleated giant cells (b); high power field revealed bronze-colored sclerotic bodies (c).View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 3Chromoblastomycosis: 10% potassium hydroxide preparation showing multiple golden brown septated “copper pennies”.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Thus, in resource-limited areas, a high level of clinical suspicion combined with relatively inexpensive investigations can facilitate rapid diagnosis and prevent complications of CBM. The authors have no competing interest to declare. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.