Chromoblastomycosis: A Single Centre Clinical Laboratory Experience of Seven Years (2016-2022) and Literature Review From Pakistan.

BACKGROUND: Chromoblastomycosis (CBM) is a chronic infection of skin and subcutaneous tissue. CBM cases have been reported in local literature from Pakistan with heterogenous demographic, diagnostic and therapeutic information. The objective of this study is to share the experience of CBM from a large tertiary care hospital laboratory in Pakistan. METHOD: This was a retrospective observational study. Histopathology and microbiology data of suspected CBM between 2016 and 2022 was retrieved. Patients' demographics, site of involvement, histopathological findings and positive microbiology cultures were assessed. Literature search on Google Scholar, PubMed and PakMediNet was done between 1990 and 2023 with multiple terms. RESULT: A total of 16 CBM cases were identified; 14 were histopathology positive and two were both histopathology and culture positive. The median age was 21 years, and 11 patients were male. The predominant site was lower extremities followed by the face. Severe acanthosis, hyperkeratosis and granuloma with sclerotic bodies were observed in all histopathology slides. Alternaria spp. and Phialophora spp. were isolated from two culture-positive cases. A total of nine cases of CBM were reported from Pakistan in PubMed non-indexed journal. CONCLUSION: CBM is not a commonly thought of disease when evaluating skin lesions in Pakistan. A high index of suspicion when assessing patients who may have a history of trauma, exposure to soil and suggestive lesions is reasonable. An integrated approach between clinicians, histopathologist and microbiologist is required to do early identification and therapeutic interventions.

Successful management of chromoblastomycosis utilizing conventional antifungal agents and imiquimod therapy.

Chromoblastomycosis (CBM), a chronic fungal infection affecting the skin and subcutaneous tissues, is predominantly caused by dematiaceous fungi in tropical and subtropical areas. Characteristically, CBM presents as plaques and nodules, often leading to scarring post-healing. Besides traditional diagnostic methods such as fungal microscopy, culture, and histopathology, dermatoscopy and reflectance confocal microscopy can aid in diagnosis. The treatment of CBM is an extended and protracted process. Imiquimod, acting as an immune response modifier, boosts the host's immune response against CBM, and controls scar hyperplasia, thereby reducing the treatment duration. We present a case of CBM in Guangdong with characteristic reflectance confocal microscopy manifestations, effectively managed through a combination of itraconazole, terbinafine, and imiquimod, shedding light on novel strategies for managing this challenging condition.

Misleading subcutaneous mycosis: a case report of subsequent clinical mycetoma-like and histological chromoblastomycosis-like lesions.

Hyalohyphomycosis and phaeohyphomycosis are groups of mycoses caused by several agents and show different clinical manifestations. We report a case of an immunocompromised patient who presented rare manifestations of opportunistic mycoses: mycetoma-like hyalohyphomycosis on his right foot caused by Colletotrichum gloeosporioides, followed by cutaneous phaeohyphomycosis on his right forearm caused by Exophiala oligosperma. Further to the rarity of this case, the patient's lesion on the foot shows that the clinical aspects of mycetomas could falsely appear in other fungal infections similar to hyalohyphomycosis. We also show that the muriform cells that were seen in the direct and anatomopathological examination of the skin are not pathognomonic of chromoblastomycosis, as observed in the lesion of the patient's forearm.

Nodular lesions of the buttock for 20 years: the challenge of chromoblastomycosis in non-endemic settings.

Chromoblastomycosis is an implantation mycosis of the skin caused by certain species of melanised fungi. A man in his 50s, born in Kerala but living in England for 14 years, presented with a nodular lesion on his left buttock, which had been present for 20 years. Biopsy revealed muriform cells and fungal culture isolated Fonsecaea spp, consistent with a diagnosis of chromoblastomycosis. Treatment with oral terbinafine was initiated and changed to itraconazole based on results of antifungal susceptibility. Drug intolerance and low drug levels of itraconazole necessitated change to voriconazole and topical terbinafine. Despite long-term combined therapy, the lesions worsened, and the patient opted for surgical excision abroad. Recurrence was evident at surgical sites and combined therapy continues. Chromoblastomycosis is an insidious and burdensome neglected tropical disease. Within non-endemic countries, diagnosis remains challenging. A travel history and appropriate fungal investigations are vital.

Comparison of the antifungal activity of the pyrimidine analogs flucytosine and carmofur against human-pathogenic dematiaceous fungi.

Chromoblastomycosis (CBM) and pheohyphomycosis (PHM) are the most common implantation mycoses caused by dematiaceous fungi. In the past, flucytosine (5-FC) has been used to treat CBM, but development of resistance is common. Carmofur belongs to the same class as 5-FC and has in vitro inhibitory activity against the main agents of CBM and PHM. The aim of this study was to compare the action of these two pyrimidine analog drugs against CBM and PHM agents. The minimum inhibitory concentration (MIC) and the selectivity index based on cytotoxicity tests of these two drugs against some agents of these mycoses were determined, with carmofur presenting a higher selectivity index than 5-FC. Carmofur demonstrated here synergistic interactions with itraconazole and amphotericin B against Exophiala heteromorpha, Fonsecaea pedrosoi, Fonsecaea monophora, and Fonsecaea nubica strains. Additionally, carmofur plus itraconazole demonstrated here synergism against a Phialophora verrucosa strain. To evaluate the development of carmofur resistance, passages in culture medium containing subinhibitory concentrations of this pyrimidine analog were carried out, followed by in vitro susceptibility tests. Exophiala dermatitidis quickly developed resistance, whereas F. pedrosoi took seven passages in carmofur-supplemented medium to develop resistance. Moreover, resistance was permanent in E. dermatitidis but transient in F. pedrosoi. Hence, carmofur has exhibited certain advantages, albeit accompanied by limitations such as the development of resistance, which was expected as with 5-FC. This underscores its therapeutic potential in combination with other drugs, emphasizing the need for a meticulous evaluation of its application in the fight against dematiaceous fungi.

Resazurin to determine the minimum inhibitory concentration on antifungal susceptibility assays for Fonsecaea sp. using a modified EUCAST protocol.

Chromoblastomycosis is a fungal chronic disease, which affects humans, especially in cutaneous and subcutaneous tissues. There is no standard treatment for Chromoblastomycosis, and it is a therapeutic challenge, due natural resistance of their causative agents, inadequate response of patients and common cases of relapse. Protocols for determination of antifungal drugs susceptibility are not standardized for chromoblastomycosis agents and endpoint definition is usually based on visual inspection, which depends on the analyst, making it sometimes inaccurate. We presented a colorimetric and quantitative methodology based on resazurin reduction to resofurin to determine the metabolic status of viable cells of Fonsecaea sp. Performing antifungal susceptibility assay by a modified EUCAST protocol allied to resazurin, we validated the method to identify the minimum inhibitory concentrations of itraconazole, fluconazole, amphotericin B, and terbinafine for eight Fonsecaea clinical isolates. According to our data, resazurin is a good indicator of metabolic status of viable cells, including those exposed to antifungal drugs. This work aimed to test resazurin as an indicator of the metabolic activity of Fonsecaea species in susceptibility assays to antifungal drugs. Species of this genus are the main causative agents of Chromoblastomycosis, which affects humans.

An Experimental Model of Chromoblastomycosis Caused by Fonsecaea sp. Species.

The experimental rodent models for the fungal disease are a handy tool for understanding host-fungus interactions. To Fonsecaea sp., one of the causative agents of chromoblastomycosis, there is an extra challenge because the animals preferably used show a spontaneous cure; so until now, there is no model to reproduce the long-term disease similar to human chronic disease. In this chapter, we described an experimental model using rats and mice with a subcutaneous route, with the checkpoints of acute-like and chronic-like lesion analysis comparable with human lesions, the fungal burden, and the lymphocytes investigation.

New methylene blue-mediated photodynamic inactivation of multidrug-resistant Fonsecaea nubica infected chromoblastomycosis in vitro.

Chromoblastomycosis is a fungal disease presented with local warty papule, plaque, and verrucous nodules. In addition, the incidence and drug resistance of chromoblastomycosis are increasing each year worldwide. Photodynamic therapy is a promising method to treat mycoses. The purpose of this study was to evaluate the effect of new methylene blue (NMB)-induced PDT on multidrug-resistant chromoblastomycosis in vitro. We isolated one wild-type strain pathogen from one clinical patient diagnosed with chromoblastomycosis for over 27 years. The pathogen was identified by histopathology, the morphology of fungal culture, and genetic testing. Drug susceptibility testing was performed on the isolate. It was cultured with logarithmic growth phase spore in vitro and incubated with different concentrations of NMB for 30 min, and received illumination by red light-emitted diode with different light doses. After photodynamic treatment, the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were conducted. The pathogen was Fonsecaea nubica, and it was resistant to itraconazole, terbinafine, amphotericin B, voriconazole andcaspofungin. At the same NMB concentration, the sterilization efficiency of NMB-photodynamic therapy (PDT) on F. nubica increased with increasing light intensity; F. nubica was completely killed at 25 µmol/L NMB with a light dose of 40 J/cm2 or 50 µmol/L NMB and light doses of ≥ 30 J/cm2. SEM and TEM observed ultrastructural changes after PDT. NMB-PDT inactivates the survival of multidrug-resistant F. nubica in vitro; it therefore has the potential to become an alternative or adjuvant treatment for refractory chromoblastomycosis.

Draft Genome Sequence of the Rhinocladiella similis Clinical Isolate CBS 149759.

Rhinocladiella similis is a melanized fungi involved in chromoblastomycosis. R. similis genome has never been sequenced, therefore we propose the first draft genome of R. similis.

Chromoblastomycosis: A Rare Presentation With Polymorphic Cutaneous Lesions And Bone Involvement, Caused By Exophiala Janselmei.

Chromoblastomycosis, a chronic fungal infection of skin and subcutaneous tissue arises as a result of traumatic inoculation of exposed areas of the body. We present a unique case of chromoblastomycosis caused by Exophiala janselmei in a female farmer who presented with multiple smooth non-tender nodules on trunk and limbs for 5 years and pigmented indurated plaques on her face for 2 years along with deformities of her hands. Imaging investigations revealed multiple lytic lesions in the bones of the upper and lower limbs. Histopathological findings showed characteristic sclerotic bodies, consistent with the diagnosis of chromoblastomycosis. She was started on a combination of oral antifungals with a good response. This case highlights the importance of high suspicion and early diagnosis of deep fungal infections in order to avoid disfigurement and comorbidities.

Treatment responses in patients with chromoblastomycosis to itraconazole in Madagascar.

INTRODUCTION: Chromoblastomycosis (CBM) is a chronic fungal infection of the skin and subcutaneous tissue caused by several pigmented fungi. It is frequently found in tropical and subtropical areas like Madagascar. This study primarily discusses the effects of antifungal therapy while also describing the epidemiological, clinical, and pathological features of CBM in our patients. METHODS: From March 2013 to January 2019, a descriptive prospective study on CBM patients was undertaken. The study included patients with CBM who had received antifungal treatment for at least 3 months. Itraconazole 200 mg was given to patients every day for ˃3 months. Results were assessed at the 6th and 12th months and classified as major responses, minor responses to treatment, or failure. RESULTS: A total of 29 cases of CBM were included. The mean age of patients was 42.02 years. They primarily worked in rural areas. Infected men were more prevalent. At the end of the 12th month of itraconazole therapy, 3 patients presented major responses, 14 patients had minor responses to treatment, and 12 had been lost to follow-up. The clinical response of CBM to treatment was correlated to the severity and the long course of CBM. When compared with CBM caused by Cladophialophora, CBM caused by Fonsecaea showed a greater clinical response. CONCLUSION: These findings demonstrated that CBM lesions are recalcitrant and difficult to treat.

Chromoblastomycosis (CBM) is a chronic fungal infection of the skin and subcutaneous tissue commonly seen in tropical and subtropical areas. This study mainly discusses the therapeutic while also describing the epidemiological, clinical, and pathological features of CBM in Madagascar.

New possibilities for chromoblastomycosis and phaeohyphomycosis treatment: identification of two compounds from the MMV Pathogen Box® that present synergism with itraconazole.

BACKGROUND: Black fungi of the Herpotrichiellaceae family are agents of chromoblastomycosis and phaeohyphomycosis. There are few therapeutic options for these infections and it is common to associate antifungal drugs in their treatment. OBJECTIVES: To investigate the Medicines for Malaria Venture (MMV) Pathogen Box® for possible compounds presenting synergism with antifungal drugs used to treat black fungal infections. METHODS: An initial screening of the Pathogen Box® compounds was performed in combination with itraconazole or terbinafine at sub-inhibitory concentrations against Fonsecaea pedrosoi. Hits were further tested against eight Herpotrichiellaceae using the checkerboard method. FINDINGS: No synergism was observed with terbinafine. MMV687273 (SQ109) and MMV688415 showed synergism with itraconazole against F. pedrosoi. Synergism of these compounds was confirmed with some black fungi by the checkerboard method. SQ109 and itraconazole presented synergism for Exophiala dermatitidis, F. pedrosoi, F. monophora and F. nubica, with fungicidal activity for F. pedrosoi and F. monophora. MMV688415 presented synergism with itraconazole only for F. pedrosoi, with fungicidal activity. The synergic compounds had high selectivity index values when combined with itraconazole. MAIN CONCLUSIONS: These compounds in combination, particularly SQ109, are promising candidates to treat Fonsecaea spp. and E. dermatitidis infections, which account for most cases of chromoblastomycosis and phaeohyphomycosis.

Chromoblastomycosis: A case series from Eastern China.

Chromoblastomycosis (CBM) is a chronic fungal infection of the cutaneous and subcutaneous tissues caused by brown pigmented fungi. Fonsecaea monophora is one of the most common pathogens of CBM in China. Most formal cases have been reported from Southern China, however, the infection is not uncommon in Eastern China where very few case series are available. To describe the clinical aspects of CBM, we report a series of 11 cases between 2018 and 2021 at a single medical center in Eastern China. The patients were predominately male (n = 9) and the disease duration ranged from 3 months to 20 years. Plaque type lesions were the most common clinical manifestations. There were 7 cases of mild forms and 3 cases of severe forms. Among the 3 severe cases, one case gave up treatment due to economic poverty; one case did not respond to a 1-year systemic treatmen; one case was cured by combination therapy of 10 months. Other cases were cured by treatment with antifungal agents. All cases of direct mycological examination were positive. All isolates were identified by morphology and sequencing of the the ITS regions of ribosomal DNA, Ten were F. monophora and 1 was Cladophialophora carrionii. All cases had been evaluated at other clinics, where 8 cases were misdiagnosed as other diseases. As a neglected tropical disease (NTD), CBM is still a major challenge in the field of dermatology, especially in its severe clinical forms. As an effective and simple diagnostic method of CBM, direct microscopic examination should be further promoted in rural hospitals.

[Chromoblastomycosis. First allochthonous case treated in Chile]. / Cromoblastomicosis. Primer caso alóctono tratado en Chile.

Chromoblastomycosis is a fungal infection of the skin and subcutaneous tissue, of chronic evolution, caused by dematiaceous fungi. The disease occurs worldwide, mainly in tropical and subtropical regions, but in regions like Chile there is only one report of a human case more than 30 years ago. We present the case of a 46-year-old Haitian man, resident in Chile, with verrucous plaques in the right anterior tibial area of one year of evolution. The diagnosis of chromoblastomycosis was confirmed when muriform cells and dematiaceous colonies were observed in the histopathological analysis and the direct microscopy, respectively. After six months of treatment with systemic antimycotics and cryotherapy, complete remission of the lesions was achieved.

Molecular epidemiology and clinical-laboratory aspects of chromoblastomycosis in Mato Grosso, Brazil.

INTRODUCTION: Chromoblastomycosis is a disease caused by melanized fungi, primarily belonging to the genera Fonsecaea and Cladophialophora, mainly affecting individuals who are occupationally exposed to soil and plant products. This research aimed to determine the clinical, epidemiological and laboratory characteristics of chromoblastomycosis in the state of Mato Grosso, Brazil. MATERIALS AND METHODS: Patients diagnosed with chromoblastomycosis treated at the Júlio Müller University Hospital, Cuiabá, Brazil, from January 2015 to December 2020, whose isolates were preserved in the Research Laboratory of the Faculty of Medicine of the Federal University of Mato Grosso. Isolates were identified by partly sequencing the Internal Transcribed Spacer (ITS) and ß-tubulin (BT2) loci. AFLP fingerprinting was used to explore the genetic diversity. Susceptibility to itraconazole, voriconazole, 5-fluorocytosine, terbinafine and amphotericin B was determined by the broth microdilution technique. RESULTS: Ten patients were included, nine were male (mean age = 64.1 years). Mean disease duration was 8.6 years. Lesions were mainly observed in the lower limbs. Predominant clinical forms were verrucous and scarring. Systemic arterial hypertension and type II diabetes mellitus were the predominant comorbidities. Leprosy was the main concomitant infectious disease. Fonsecaea pedrosoi was the unique aetiological agent identified with moderate genetic diversity (H = 0.3934-0.4527; PIC = 0.3160-0.3502). Antifungal agents with the highest activity were terbinafine, voriconazole and itraconazole. CONCLUSION: Chromoblastomycosis is affecting the poor population in rural and urban areas, mainly related to agricultural activities, with F. pedrosoi being the dominant aetiologic agent. All isolates had low MICs for itraconazole, voriconazole and terbinafine, confirming their importance as therapeutic alternatives for chromoblastomycosis.

Tuberculosis verrucous cutis mimicking chromoblastomycosis: A case report and diagnostic challenges.

Tuberculosis verrucous cutis (TBVc) is a skin infection caused by M. tuberculosis, characterized by the presence of a solitaire verrucous plaque but may present as a varies of different clinical morphologies on the finger and or feet. The diagnosis is often late because of its mimicking other diseases with different etiology. Bacterial culture examination is negative because there are few pathogens in the lesion. Meanwhile, other diagnostic methods provide lower sensitivity and specificity which add further diagnostic challenges. We presented one case report of TBVc mimicking chromoblastomycosis. A 26-year-old man complain a multiple papule-plaque verrucose on the dorsum of the right foot and extending to all of fingers for 2 years ago. The first lesion appears as a small papule verrucous then progressively to form plaque with curst yellow-red and central healing. Examination of bacterial culture with Ziehl-Neelsen stain and GeneXpert did not find M. tuberculosis but could not rule out the diagnosis of TBVc. The diagnosis was established based on the correlation of clinical manifestations and dermoscopy with histopathological examination. To date, there is no gold standard for TBVc testing. Correlation analysis of clinical manifestations, dermoscopy, and histopathology can be considered to establish the diagnosis of TBVc, especially if the culture is negative and the limitations of polymerase chain reaction tools.

Pathogenicity and Growth Conditions Modulate Fonsecaea Extracellular Vesicles' Ability to Interact With Macrophages.

Chromoblastomycosis (CBM) is a chronic cutaneous and subcutaneous mycosis caused by black, dimorphic, and filamentous fungi of the Herpothrichiellaceae family, such as species of the genus Fonsecaea. These fungi can switch between the saprophytic forms (conidia and hyphae) and the pathogenic form, the muriform cells (MCs), which is considered an essential mechanism for fungal virulence. Nearly all types of cells can produce membranous structures formed by a lipid bilayer that communicate extracellularly with other cells, known as "extracellular vesicles" (EVs), which may act as virulence factors, as observed for several species of pathogenic fungi. Our findings demonstrated for the first time that F. pedrosoi, F. nubica, and F. erecta produce EVs in response to nutritional conditions. The EVs varied in sterol and protein contents, size, and morphology. Moreover, the EVs induced different cytokine and nitric oxide release patterns by bone marrow-derived macrophages (BMDMs). The EVs activated IL-1ß production, possibly acting as the first signal in inflammasome activation. Unlike the pathogenic species, the EVs isolated from F. erecta did not significantly stimulate TNF and IL-10 production in general. Overall, these results demonstrated that different species of Fonsecaea produce EVs capable of modulating pro- and anti-inflammatory cytokine and nitric oxide production by BMDMs and that growth conditions affected the immunomodulatory capacities of the EVs as well as their size, content, and morphology.