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.

Chromoblastomycosis: A Potential Mimic of Squamous Cell Carcinoma in Transplant Recipients.

Chromoblastomycosis (CBM), also known as chromomycosis is a chronic, granulomatous fungal infection of the skin and subcutaneous tissue. It usually occurs by the traumatic inoculation of various dematiaceous fungi and is more common in the developing world. This condition is rare in North America and the developed world. Herein, we present a case of a 75-year-old man who received a bilateral lung transplant 4 months prior and presented for evaluation of a painful, erythematous papule on the elbow which was diagnosed as CBM. This case highlights that immunosuppression used in patients who undergo solid organ transplantation not only increases the risk of opportunistic infections like CBM but can also be confused for cutaneous squamous cell carcinoma as both these entities share many overlapping clinical and histopathologic features and may be a potential source of misdiagnosis.

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.

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.

Potassium iodide enhances the killing effect of methylene blue mediated photodynamic therapy against F. monophora.

BACKGROUND: Chromoblastomycosis (CMB) is a chronic granulomatous fungal infection that affect the skin and subcutaneous tissues. It is clinically problematic due to limited treatment options, low cure rates, and high rates of relapse. This underscores the necessity for innovative treatment approaches. In this study, potassium iodide (KI) combined with Methylene Blue (MB) mediated antimicrobial photodynamic therapy (PDT) were assessed in the treatment of Fonsecaea monophora (F. monophora) both in vitro and in vivo. And the underlying mechanism that contributes to the efficacy of this treatment approach was investigated. METHODS: In vitro experiments were conducted using different combinations and concentrations of MB, KI, and 660 nm light (60 mW/cm2) to inhibit F. monophora. The study was carried out using colony-forming unit (CFU) counts and scanning electron microscopy (SEM). The production of singlet oxygen (1O2), free iodine (I2), hydrogen peroxide (H2O2), and superoxide anion during the KI combined MB-mediated antimicrobial PDT process was also detected. In vivo experiments were developed using a Balb/c mouse paw infection model with F. monophora and treated with PBS, 10 mM KI, 2 mM MB +100 J/cm² and 10 mM KI+2 mM MB +100 J/cm² respectively. Inflammatory swelling, fungal load and histopathological analyses of the mouse footpads were assessed. RESULTS: KI enhanced the killing effect of MB-mediated antimicrobial PDT on the conidial spores of F. monophora at the cell and infected animal model level. During the process, the main antimicrobial agents in KI combined with MB- mediated antimicrobial PDT could produce stronger toxic active species including free I2 and H2O2. CONCLUSION: KI combined with MB-mediated antimicrobial PDT could be an effective adjunct therapy for treating CBM.

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.

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.

Environmental influences on induction of itching and scratching using immersive virtual reality.

Chronic itching is a serious and uncomfortable condition. The scratch response might result in a vicious cycle of alternating itching and scratching. To develop psychological interventions for people suffering from chronic itching and to break the vicious itch-scratching-itch cycle, it is important to elucidate which environmental factors trigger itch sensations. Virtual reality (VR) techniques provide a useful tool to examine specific content characteristics in a three-dimensional (3D VR) environment and their influences on itch sensations and scratching behaviour. This article describes two experiments in which we focused on the effects of environmental information on itching and scratching behaviour. Additionally, in the second experiment, we examined the influence of having a chronic skin condition on sensitivity to itch induction. We found evidence for the importance of the content of audio-visual materials for the effectiveness in inducing feelings of itch in the observers. In both experiments, we observed significantly higher levels of perceived itch in the itch-inducing conditions than in the control condition. Moreover, the results showed that elevated levels of perceived itch were associated with an increase in scratching behaviours, which was especially salient in the contagious itch condition, in which perceived itch was accompanied by a significant increase in the number of scratches. Experiment 2 additionally showed increased perceived itch levels in participants who reported having a chronic skin condition, reflecting higher sensitivity to itch-inducing audio-visual stimuli in this group than in participants without a chronic skin condition. Based on the results we concluded that directing attention towards itch- or scratch aspects of related information in the environment and to the consequences for one's own skin are effective tools to induce itch sensations and scratching behaviour. This knowledge provides tools for developing novel strategies in advising and treating people suffering from chronic itching and breaking the vicious itch-scratching-itch cycle.

Subcutaneous mycoses: Endemic but neglected among the Neglected Tropical Diseases in Ethiopia.

BACKGROUND: Subcutaneous (deep) mycoses are a chronic infectious disease of the skin and underlying structures endemic in tropical countries. The disease has serious medical and socioeconomic consequences for patients, communities and health services in endemic areas. The inclusion of mycetoma and other subcutaneous mycoses in the list of Neglected Tropical Diseases by WHO highlights the need to assess the burden of these diseases and establish control programs where necessary. In Ethiopia no strategies can be devised because of a lack of epidemiologic information. To address this evidence gap, we performed a national rapid assessment of the geographic distribution of subcutaneous mycoses. METHODOLOGY: We conducted a rapid retrospective assessment using hospital records to identify all suspected and confirmed cases of subcutaneous mycoses in 13 referral hospitals across the country between 2015 and 2022. In each hospital the logbooks were reviewed for diagnoses of subcutaneous mycosess, as diagnosed per routine practice. Descriptive analysis was done. RESULT: From 13 hospitals we extracted 143 cases of subcutaneous mycoses, registered from July 2018 to September 2022. 118 (82.5%) patients were diagnosed as mycetoma, 21 (14.7%) as chromoblastomycosis and the remaining 4 (2.8%) as sporotrichosis. The mean age of patients was 35.8 years (SD = 14.5). 101 (70.6%) patients were male and 96 (67.1%) patients were farmers. 64 (44.8%) cases were from the Tigray regional state. 56 (65.9%) patients had information on diagnostic microscopic evaluation: for mycetoma histopathologic evaluation and fine needle aspiration cytology had a higher positivity rate while for chromoblastomycosis potassium hydroxide (KOH) staining had a better yield. The main clinical presentations were nodules, sinuses and infiltrative plaques on the skin. Radiologic findings of bone involvement was present in some. CONCLUSIONS: Mycetoma and other subcutaneous mycoses are endemic in Ethiopia, with cases reported from almost all regions with the highest cases numbers reported from the northern part of the country. A routine program and systems should be developed to identify and document the burden of subcutaneous fungal infections in the country. Diagnosis and treatment guidelines should be developed.

Cromoblastomicosis: abordaje con terapia combinada / Chromoblastomycosis: a combination therapy approach

La cromoblastomicosis es una micosis de implantación crónica y progresiva causada por diversos hongos de la familia Dematiaceae. En Latinoamérica, las especies en-contradas con más frecuencia son Fonsecaea pedrosoi y Cladophialophora carrionii. El tratamiento de esta micosis puede ser un desafío por la falta de respuesta y la recidiva, en especial en individuos con lesiones crónicas y extensas.Se presenta un individuo con recaída de cromoblastomico-sis (causada por Fonsecaea pedrosoi) en miembro inferior derecho que había realizado tratamiento incompleto con terbinafina e itraconazol. El paciente respondió de mane-ra favorable al retratamiento con itraconazol y terbinafina combinado con resección quirúrgica parcial de la lesión e injerto de piel en sitio quirúrgico

Chromoblastomycosis is a chronic and subcutaneous mycosis caused by various dematiaceous fungi, In Latin America, the most frequently found species are Fonsecaea pedrosoi and Cladophialophora carrionii.Treatment is a challenge because of the lack of response and recurrence in in some cases, especially in patients with extensive and chronic lesions.We report an individual with relapse of chromoblastomycosis (by Fonsecaea pedrosoi) in the right lower limb, who had undergone incomplete treatment with terbinafine and itraconazole. The patient responded favorably to retreatment with itraconazole and terbinafine combined with partial surgical resection of the lesion and skin grafting at the surgical site.

Subcutaneous phaeohyphomycosis caused by Alternaria section Alternaria.

A woman presented with purulent infiltrating plaques on her hands and arms after a 7-year history of nephrotic syndrome. She was ultimately diagnosed with subcutaneous phaeohyphomycosis, which is caused by Alternaria section Alternaria. The lesions completely resolved after 2 months of antifungal treatment. Interestingly, spores (round-shaped cells) and hyphae were observed in the biopsy and pus specimens, respectively. This case report highlights that distinguishing subcutaneous phaeohyphomycosis from chromoblastomycosis may be difficult if the diagnosis is solely based on pathological findings. It also emphasizes that the parasitic forms of the dematiaceous fungi in immunosuppressed hosts may vary with the site and environment.

Cromoblastomicosis verrugosa-cicatricial multifocal: una entidad desatendida en Colombia / Multifocal verrucous-cicatricial chromoblastomycosis: a neglected disease in Colombia

La cromoblastomicosis es una micosis subcutánea crónica de presentación clínica heterogénea que afecta principalmente a poblaciones de escasos recursos, lo que sumado al acceso limitado a los servicios de salud condiciona el retraso en el diagnóstico y tratamiento, ocasionando secuelas físicas graves. Se describe el caso de un hombre de 50 años con lesiones cutáneas verrugosas y cicatriciales de 30 años de evolución en la extremidad inferior y mano izquierda, además en cara en los últimos cinco años. Se realizó el diagnóstico de cromoblastomicosis de presentación multifocal y clínica mixta, con examen directo e histopatología compatibles, y cultivo para hongos positivo para Fonsecaea pedrosoi. Se indicó tratamiento oral con itraconazol y seguimiento clínico. Reconocer esta entidad es crucial para un diagnóstico y tratamiento oportunos, con el fin de evitar secuelas físicas y estigmatización secundaria. Se debe fortalecer en la atención primaria el reconocimiento de patologías desatendidas y de incidencia subestimada en Colombia, con una presentación multifocal mixta atípica y de un tiempo de evolución prolongado. El examen directo KOH es un herramienta accesible y económica en los primeros niveles de atención que puede contribuir al enfoque diagnóstico.

Chromoblastomycosis is a chronic subcutaneous mycosis with heterogeneous clinical presentation. It mainly affects low-income populations, which added to limited access to health services delays diagnosis and treatment, causing serious physical sequelae. We describe the case of a 50-year-old man with warty and cicatricial skin lesions of 30 years of evolution, at the level of left lower limb and left hand, with face involvement in the last five years. A diagnosis of chromoblastomycosis with multifocal and mixed clinical presentation was made, based on compatible direct examination and histopathology, and positive fungal culture for Fonsecaea pedrosoi. Oral treatment with itraconazole and clinical followup were stablished. Recognizing this entity is crucial for timely diagnosis and treatment, to avoid physical sequelae and secondary stigmatization. Primary health care should be strengthened for the recognition of neglected diseases whose incidence is underestimated in Colombia, with an atypical mixed multifocal presentation and a long evolution time. The KOH direct examination is an accessible and economical tool in the first levels of care that can contribute to the diagnostic approach.