Histopathology of chromoblastomycosis

Neutrophil extracellular traps (NETs) and Th-2 dominant immune responses in chronic granulomatous chromobalstomycosis

Chromoblastomycosis (CBM), a chronic, granulomatous, suppurative mycosis of the skin and subcutaneous tissue, is caused by several dematiaceous fungi. The formation of granulomas, tissue proliferation, and fibrosis in response to these pathogenic fungi is believed to be intricately linked to host immunity. To understand this complex interaction, we conducted a comprehensive analysis of immune cell infiltrates, neutrophil extracellular traps (NETs) formation, and the fibrosis mechanism in 20 CBM lesion biopsies using immunohistochemical and immunofluorescence staining methods. The results revealed a significant infiltration of mixed inflammatory cells in CBM granulomas, prominently featuring a substantial presence of Th2 cells and M2 macrophages. These cells appeared to contribute to the production of collagen I and III in the late fibrosis mechanism, as well as NETs formation. The abundance of Th2 cytokines may act as a factor promoting the bias of macrophage differentiation toward M2, which hinders efficient fungal clearance while accelerates the proliferation of fibrous tissue. Furthermore, the expression of IL-17 was noted to recruit neutrophils, facilitating subsequent NETs formation within CBM granulomas to impede the spread of sclerotic cells. Understanding of these immune mechanisms holds promise for identifying therapeutic targets for managing chronic granulomatous CBM.

New Immunological Markers in Chromoblastomycosis-The Importance of PD-1 and PD-L1 Molecules in Human Infection

The pathogenesis of chromoblastomycosis (CBM) is associated with Th2 and/or T regulatory immune responses, while resistance is associated with a Th1 response. However, even in the presence of IFN-γ, fungi persist in the lesions, and the reason for this persistence is unknown. To clarify the factors associated with pathogenesis, this study aimed to determine the polarization of the cellular immune response and the densities of cells that express markers of exhaustion in the skin of CBM patients. In the skin of patients with CBM, a moderate inflammatory infiltrate was observed, characterized primarily by the occurrence of histiocytes. Analysis of fungal density allowed us to divide patients into groups that exhibited low and high fungal densities; however, the intensity of the inflammatory response was not related to mycotic loads. Furthermore, patients with CBM exhibited a significant increase in the number of CD4+ and CD8+ cells associated with a high density of IL-10-, IL-17-, and IFN-γ-producing cells, indicating the presence of a chronic and mixed cellular immune response, which was also independent of fungal load. A significant increase in the number of PD-1+ and PD-L1+ cells was observed, which may be associated with the maintenance of the fungus in the skin and the progression of the disease.

Repurposing Benzimidazoles against Causative Agents of Chromoblastomycosis: Albendazole Has Superior In Vitro Activity Than Mebendazole and Thiabendazole

Chromoblastomycosis (CBM) is a neglected human implantation mycosis caused by several dematiaceous fungal species. Currently available therapy is usually associated with physical methods, especially surgery, and with high refractoriness. Therefore, drug discovery for CBM is essential. Drug repositioning is a strategy used to facilitate the discovery of new treatments for several diseases. The aim of this study was to discover substances with antifungal activity against CBM agents from a collection of drugs previously approved for use in human diseases. A screening was performed with the NIH Clinical Collection against Fonsecaea pedrosoi. Ten substances, with clinical applicability in CBM, inhibited fungal growth by at least 60%. The minimum inhibitory concentration (MIC) of these substances was determined against other CBM agents, and the benzimidazoles albendazole, mebendazole and thiabendazole presented the lowest MIC values. The selectivity index, based on MIC and cytotoxicity of these substances, revealed albendazole to be more selective. To investigate a possible synergism of this benzimidazole with itraconazole and terbinafine, the chequerboard method was used. All interactions were classified as indifferent. Our current results suggest that benzimidazoles have repositioning potential against CBM agents. Albendazole seems to be the most promising, since it presented the highest selectivity against all dematiaceous fungi tested.

Reviewing the Etiologic Agents, Microbe-Host Relationship, Immune Response, Diagnosis, and Treatment in Chromoblastomycosis

Chromoblastomycosis (CBM) is a neglected human disease, caused by different species of pigmented dematiaceous fungi that cause subcutaneous infections. This disease has been considered an occupational disease, occurring among people working in the field of agriculture, particularly in low-income countries. In 1914, the first case of CBM was described in Brazil, and although efforts have been made, few scientific and technological advances have been made in this area. In the field of fungi and host cell relationship, a very reduced number of antigens were characterized, but available data suggest that ectoantigens bind to the cell membrane of host cells and modulate the phagocytic, immunological, and microbicidal responses of immune cells. Furthermore, antigens cleave extracellular proteins in tissues, allowing fungi to spread. On the contrary, if phagocytic cells are able to present antigens in MHC molecules to T lymphocytes in the presence of costimulation and IL-12, a Th1 immune response will develop and a relative control of the disease will be observed. Despite knowledge of the resistance and susceptibility in CBM, up to now, no effective vaccines have been developed. In the field of chemotherapy, most patients are treated with conventional antifungal drugs, such as itraconazole and terbinafine, but these drugs exhibit limitations, considering that not all patients heal cutaneous lesions. Few advances in treatment have been made so far, but one of the most promising ones is based on the use of immunomodulators, such as imiquimod. Data about a standard treatment are missing in the medical literature; part of it is caused by the existence of a diversity of etiologic agents and clinical forms. The present review summarizes the advances made in the field of CBM related to the diversity of pathogenic species, fungi and host cell relationship, antigens, innate and acquired immunity, clinical forms of CBM, chemotherapy, and diagnosis.

Neutrophil-suppressive activity over T-cell proliferation and fungal clearance in a murine model of Fonsecaea pedrosoi infection

Neutrophils are essential to control several fungal infections. These cells are commonly known for their pro-inflammatory activities. However, some studies have demonstrated the anti-inflammatory properties of neutrophils during certain infectious diseases, culminating in the inhibition of T cell proliferation. Chromoblastomycosis (CBM) is a deep and progressive mycosis that affects thousands of people worldwide. Although neutrophil infiltrates are observed in the lesion histopathology, the fungus can overtake the immune system response and destroy the host-infected tissue. The present study demonstrated that neutropenic animals had an increase in the IL-6 production in the spleen and liver, followed by a lower fungal burden in these organs up to 14 days of infection. Neutropenic animals also showed a lower F. pedrosoi-specific antibody production 14-days post infection and higher T-cell proliferation in the in vitro experiments after stimulation with F. pedrosoi-purified proteins. Taken together, our results suggest that the presence of regulatory neutrophils in the mouse model of F. pedrosoi infection could act favoring the spread of the fungus and the chronicity of the infection. These findings shed light on the CBM treatment, which might target neutrophil polarization as a new therapy approach to treat CBM lesions.

Immune Sensing and Potential Immunotherapeutic Approaches to Control Chromoblastomycosis

Chromoblastomycosis (CBM) is a neglected, chronic, and progressive subcutaneous mycosis caused by different species of fungi from the Herpotrichiellaceae family. CBM disease is usually associated with agricultural activities, and its infection is characterized by verrucous, erythematous papules, and atrophic lesions on the upper and lower limbs, leading to social stigma and impacts on patients' welfare. The economic aspect of disease treatment is another relevant issue. There is no specific treatment for CBM, and different anti-fungal drug associations are used to treat the patients. However, the long period of the disease and the high cost of the treatment lead to treatment interruption and, consequently, relapse of the disease. In previous years, great progress had been made in the comprehension of the CBM pathophysiology. In this review, we discuss the differences in the cell wall composition of conidia, hyphae, and muriform cells, with a particular focus on the activation of the host immune response. We also highlight the importance of studies about the host skin immunology in CBM. Finally, we explore different immunotherapeutic studies, highlighting the importance of these approaches for future treatment strategies for CBM.

[Chromoblastomycosis]

The paper describes a case of chromoblastomycosis, a rare implantation mycosis in the Russian Federation. It gives data on the prevalence, etiology, and clinical presentations of the disease, and the diagnostic possibilities. Emphasis is laid on the leading role of a pathomorphological study in the diagnosis of chromoblastomycosis in non-endemic countries, including Russia. The clinical and pathomorphological presentations are described in detail. Histological examination detected 5-12-µm spherical or polygonal pigmented cells that are fungal elements, which allows chromoblastomycosis to be diagnosed in the cytoplasm of macrophages and extracellularly. A refusal to conduct a pathomorphological study leads to diagnostic errors and an irrational treatment policy.

Epidemiology of Subcutaneous Mycoses in Northeast India: A Retrospective Study

Background:

Subcutaneous mycoses, although rare, are frequently reported from northeast India. Their spectrum varies with geographic region.

Materials and Methods:

We evaluated clinical records and histopathological features of subcutaneous mycoses cases seen during April 2013 to March 2017.

Results:

A total of 70 patients (44 males and 26 females) of subcutaneous mycoses were analyzed. Sixty-one percent of patients were 20–60 years old. Duration of the disease ranged from 3 months to 25 years. Most common site of involvement was the lower limb (32, 46%), followed by the upper limb (25, 36%). A history of trauma was obtained from 76% of patients. Eighty-seven percent of patients were from rural area. Ninety-two percent of patients were agricultural workers. There were 30 established cases of chromoblastomycosis and 16 cases of sporotrichosis. In 24 cases, subcutaneous mycosis was suspected clinically and showed some improvement to empirical itraconazole therapy. Multifocal lesions were seen in six patients. Complication of subcutaneous mycoses in the form of invasive squamous cell carcinoma was seen in one patient. On histopathological examination, verrucous hyperplasia was seen in 93% of cases. Granulomas with suppuration were seen in 77% of cases and granulomas without suppuration were seen in 14.3% of cases. Copper penny bodies were appreciated in 42.8% of cases. Fungal culture was positive only in 55.7% of cases. There was growth of Sporothrix schenckii in 16 patients, Fonsecaea sp. in 19, Cladosporium sp. in 3, and Curvularia sp. in 1.

Conclusion:

Chromoblastomycosis was the most common subcutaneous mycoses seen in northeast India followed by sporotrichosis. The diagnosis remained a challenge in a few cases as the culture positivity was very low. Suppurative granulomas in histopathology played a corroborative role. Therapeutic trial of itraconazole for 2 months was worth trying in such cases.

Eighty Years of Mycopathologia: A Retrospective Analysis of Progress Made in Understanding Human and Animal Fungal Pathogens

Mycopathologia was founded in 1938 to 'diffuse the understanding of fungal diseases in man and animals among mycologists.' This was an important mission considering that pathogenic fungi for humans and animals represent a tiny minority of the estimated 1.5-5 million fungal inhabitants on Earth. These pathogens have diverged from the usual saprotrophic lifestyles of most fungi to colonize and infect humans and animals. Medical and veterinary mycology is the subdiscipline of microbiology that dwells into the mysteries of parasitic, fungal lifestyles. Among the oldest continuing scientific publications on the subject, Mycopathologia had its share of 'classic papers' since the first issue was published in 1938. An analysis of the eight decades of notable contributions reveals many facets of host-pathogen interactions among 183 volumes comprising about 6885 articles. We have analyzed the impact and relevance of this body of work using a combination of citation tools (Google Scholar and Scopus) since no single citation metric gives an inclusive perspective. Among the highly cited Mycopathologia publications, those on experimental mycology accounted for the major part of the articles (36%), followed by diagnostic mycology (16%), ecology and epidemiology (15%), clinical mycology (14%), taxonomy and classification (10%), and veterinary mycology (9%). The first classic publication, collecting nearly 200 citations, appeared in 1957, while two articles published in 2010 received nearly 150 citations each, which is notable for a journal covering a highly specialized field of study. An empirical analysis of the publication trends suggests continuing interests in novel diagnostics, fungal pathogenesis, review of clinical diseases especially with relevance to the laboratory scientists, taxonomy and classification of fungal pathogens, fungal infections and carriage in pets and wildlife, and changing ecology and epidemiology of fungal diseases around the globe. We anticipate that emerging and re-emerging fungal pathogens will continue to cause significant health burden in the coming decades. It remains vital that scientists and physicians continue to collaborate by learning each other's language for the study of fungal diseases, and Mycopathologia will strive to be their partner in this increasingly important endeavor to its 100th anniversary in 2038 and beyond.

Molecular identification and antifungal susceptibility profiles of clinical strains of Fonsecaea spp. isolated from patients with chromoblastomycosis in Rio de Janeiro, Brazil

BACKGROUND

Chromoblastomycosis (CBM) is a difficult-to-treat chronic subcutaneous mycosis. In Brazil, the main agent of this disease is Fonsecaea pedrosoi, which is phenotypically very similar to other Fonsecaea species, differing only genetically. The correct species identification is relevant since different species may differ in their epidemiologic aspects, clinical presentation, and treatment response.

METHODOLOGY/PRINCIPAL FINDINGS

Partial sequencing of the internal transcribed spacer (ITS) was used to identify twenty clinical isolates of Fonsecaea spp. Their in vitro antifungal susceptibility was determined using the broth microdilution method, according to the M38-A2 protocol. Amphotericin B (AMB), flucytosine (5FC), terbinafine (TRB), fluconazole (FLC), itraconazole (ITC), ketoconazole (KTC), posaconazole (POS), voriconazole (VRC), ravuconazole (RVC), caspofungin (CAS), and micafungin (MFG) were tested. The association between ITC/TRB, AMB/5FC, and ITC/CAS was studied by the checkerboard method to check synergism. The available patients' data were correlated with the obtained laboratory results. Fonsecaea monophora (n = 10), F. pedrosoi (n = 5), and F. nubica (n = 5) were identified as CBM' agents in the study. TRB and VRC were the drugs with the best in vitro activity with minimal inhibitory concentrations (MIC) lower than 0.25 mg/L. On the other hand, FLC, 5FC, AMB, and MFG showed high MICs. The AMB/5FC combination was synergistic for three F. monophora strains while the others were indifferent. Patients had moderate or severe CBM, and ITC therapy was not sufficient for complete cure in most of the cases, requiring adjuvant surgical approaches.

CONCLUSIONS/SIGNIFICANCE

F. monophora, the second most frequent Fonsecaea species in South America, predominated in patients raised and born in Rio de Janeiro, Brazil, without cerebral involvement in these cases. TRB, VRC, and the AMB/5FC combination should be further investigated as a treatment option for CBM.

Chromoblastomycosis: tissue modifications during itraconazole treatment

Background

Histological and mycological changes during itraconazole use have not been totally established in chromoblastomycosis.

Objectives

To evaluate tissue modifications in chromoblastomycosis carriers under itraconazole treatment.

Methods

A histological retrospective study of 20 cases of chromoblastomycosis seen at the university hospital at the south of Brazil, during itraconazole 400 mg daily treatment. Patients were classified into two groups: plaque or tumor lesions, and underwent periodic evaluations every four months during three years. Hematoxylin-eosin stain was used to analyze epidermal modifications, inflammatory infiltrate and fibrosis, and Fontana-Masson stain for parasite evaluation.

Results

Fontana-Masson stain was superior to hematoxylin-eosin stain in fungal count in the epidermis (mean difference=0.14; p<0.05). The most distinct mycosis tissue responses were registered in the dermis. Epidermal thinning, granulomatous infiltrate decrease or disappearance, fibrosis increase and quantitative/morphological changes occurred during treatment.

Study limitations

Patients could not be located to have their current skin condition examined.

Conclusion

Parasitic and tissue changes verified in this study can reflect the parasite-host dynamics under itraconazole action.

Chromoblastomycosis

Chromoblastomycosis (CBM), also known as chromomycosis, is one of the most prevalent implantation fungal infections, being the most common of the gamut of mycoses caused by melanized or brown-pigmented fungi. CBM is mainly a tropical or subtropical disease that may affect individuals with certain risk factors around the world. The following characteristics are associated with this disease: (i) traumatic inoculation by implantation from an environmental source, leading to an initial cutaneous lesion at the inoculation site; (ii) chronic and progressive cutaneous and subcutaneous tissular involvement associated with fibrotic and granulomatous reactions associated with microabscesses and often with tissue proliferation; (iii) a nonprotective T helper type 2 (Th2) immune response with ineffective humoral involvement; and (iv) the presence of muriform (sclerotic) cells embedded in the affected tissue. CBM lesions are clinically polymorphic and are commonly misdiagnosed as various other infectious and noninfectious diseases. In its more severe clinical forms, CBM may cause an incapacity for labor due to fibrotic sequelae and also due to a series of clinical complications, and if not recognized at an early stage, this disease can be refractory to antifungal therapy.

Study on the organization of cellular elements in the granulomatous lesion caused by chromoblastomycosis

BACKGROUND

Chromoblastomycosis is a deep fungal infection characterized by a complex cellular granuloma. The aim of this study was to analyze the arrangement of cells responsible for the granuloma configuration of this disease by semiquantification of the cellular components of chromoblastomycosis skin biopsies.

METHODS

The cells of cutaneous biopsies slides from 100 patients with untreated chromoblastomycosis were stained with hematoxylin-eosin and the granuloma cells were evaluated by microscopic examination of the elements of each granuloma and semiquantified the number of cells through its expressivity in crosses and the histopathological variables. Their presence were coded in degrees of intensity and classified in two categories: low expression and high expression. The cells that constituted the granulomas were separated into three groups: A, B and C.

RESULTS

The chromoblastomycotic granuloma analyzed by this semiquantification of its cellular components showed that there was high expression of the elements setting up a mixed organized mycotic granuloma. It was observed that mononuclear phagocytic system (A), polymorphonuclear phagocytic system (B) and lymphoplasmocytic infiltrate (C) were located around the fungus.

CONCLUSION

The results indicated that the granuloma present in the cutaneous lesion of chromoblastomycosis is a mixed organized mycotic granuloma with high expression of the cellular components.

Chromoblastomycosis

Chromoblastomycosis is a chronic fungal infection of the skin and subcutaneous tissue. The infection usually results from a traumatic injury and inoculation of microorganism from a specific group of dematiaceous fungi (usually Fonsecaea pedrosoi, Phialophora verrucosa, Cladophialophora carrionii). In the tissues fungi produce characteristic sclerotic cells or muriform cells. Dermal lesions can range from small nodules to large papillary-like eruptions. The disease has been described worldwide but the prevalence is higher in rural populations in countries with a tropical or subtropical climate, such as Madagascar in Africa and Brazil in South America. Diagnostic techniques are based on direct examination, culture and histopathology. Despite a variety of treatment modalities, which include long courses of antifungals, surgical excision and destructive physical therapies, the disease remains one of the most difficult deep mycotic infections to eradicate.

Association of IgG immunoglobulin and subclasses level with the severity of chromoblastomycosis due to Fonsecaea pedrosoi and therapeutic response to itraconazole

Chromoblastomycosis (CBM) is a chronic, suppurative, granulomatous mycosis of the skin and subcutaneous tissues. The aim of this study was to evaluate the association between IgG antibody levels and the severity of CBM and therapeutic response of patients to itraconazole. A longitudinal study was conducted in patients with CBM due to Fonsecaea pedrosoi and in healthy subjects with chromomycin skin test (CST)+. The dosage of anti-F. pedrosoi IgG antibody performed in 47 healthy individuals with CST+ showed positivity in 97.5 %, with an average titer of 2,109 [standard deviation (SD) + 3,676)] and a mean optical density (OD) of 1.174 (SD + 0.456), showing positive correlation with the induration area of the CST (mm(2)). The level of antibodies in 55 patients with CBM expressed in OD and titration showed that, before treatment, patients with severe disease had higher levels of IgG, IgG1, IgG2, and IgG3 when compared with moderate or mild disease (p < 0.05). According to the time of treatment, the mean antibody titers of IgG, IgG1, and IgG2 were reduced after treatment (p < 0.05). In the assessment of therapeutic response, there was reduction of IgG3 and IgG titers in patients with rapid response (p < 0.05) and IgG2 on rapid and intermediate response (p < 0.05). There was clear evidence of what are the risk factors for exposure to F. pedrosoi in the daily lives of these subjects, with prospects of preventive measures for the target population. The immunological analysis shows that the antibody anti-F. pedrosoi did not exhibit a protective role against infection caused by this agent.

Plasmacytoid dendritic cells in cutaneous lesions of patients with chromoblastomycosis, lacaziosis, and paracoccidioidomycosis: a comparative analysis

Plasmacytoid dendritic cells (pDCs) are characterized by expression of CD123 and BDCA-2 (Blood Dendritic Cell Antigen 2) (CD303) molecules, which are important in innate and adaptive immunity. Chromoblastomycosis (CBM), lacaziosis or Jorge Lobo's disease (JLD), and paracoccidioidomycosis (PCM), are noteworthy in Latin America due to the large number of reported cases. The severity of lesions is mainly determined by the host's immune status and in situ responses. The dendritic cells studied in these fungal diseases are of myeloid origin, such as Langerhans cells and dermal dendrocytes; to our knowledge, there are no data for pDCs. Forty-three biopsies from patients with CBM, 42 from those with JLD and 46 diagnosed with PCM, were evaluated by immunohistochemistry. Plasmacytoid cells immunostained with anti-CD123 and anti-CD303 were detected in 16 cases of CBM; in those stained with anti-CD123, 24 specimens were obtained from PCM. We did not detect the presence of pDCs in any specimen using either antibody in JLD. We believe that, albeit a secondary immune response in PCM and CBM, pDCs could act as a secondary source of important cytokines. The BDCA-2 (CD303) is a c-type lectin receptor involved in cell adhesion, capture, and processing of antigens. Through the expression of the c-lectin receptor, there could be an interaction with fungi, similar to other receptors of this type, namely, CD207 in PCM and CD205 and CD209 in other fungal infections. In JLD, the absence of expression of CD123 and CD303 seems to indicate that pDCs are not involved in the immune response.

Revisiting the clinical and histopathological aspects of patients with chromoblastomycosis from the Brazilian Amazon region

BACKGROUND AND AIMS

Chromoblastomycosis is a chronic fungal infection caused by species of the family Dematiaceae. Fonsecaea pedrosoi is the most common etiological agent. The objective of this study was to describe the epidemiological and mycological profile of patients with chromoblastomycosis from the Amazon region of Brazil and to correlate the clinical forms with the histopathological findings and severity criteria.

METHODS

Sixty-five patients were submitted to mycological (direct, culture, and microculture) and histopathological (hematoxylin-eosin staining) examination. Severity of the disease was classified according to the criteria proposed by Carrión in 1950.

RESULTS

Most patients were males (93.8%) and laborers (89.2%). There was a predominance of verrucous lesions (55.4%), which were mainly found on the lower limbs (81.5%). Two major types of tissue reaction were observed: a granulomatous reaction characterized by the formation of suppurative granulomas rich in fungal cells, which were almost always seen in verrucous lesions, and a reaction characterized by the formation of tuberculoid granulomas with few parasites, which were mainly found in well-delimited erythematous plaque-like and cicatricial lesions (p = 0.0001). A peculiar type of organized mycotic granuloma was observed in 20 subjects. Suppurative granulomas were more frequently detected in severe lesions (p = 0.0189) and in lesions with a duration of >10 years (p = 0.0408).

CONCLUSIONS

These results suggest that verrucous lesions present a less competent inflammatory tissue response than patients who develop a well-formed tuberculoid reaction. The latter is associated with a more effective immune response as observed in the limited clinical forms of chromoblastomycosis.

Clinical, epidemiological and mycological report on 65 patients from the Eastern Amazon region with chromoblastomycosis

BACKGROUND: Chromoblastomycosis is a chronic fungal infection caused by fungi from the Dematiaceae family. According to several studies, Fonsecaea pedrosoi is the most common of these fungi. The infection is more common in tropical countries, with the Brazilian state of Pará having one of the largest infected populations worldwide. The disease is difficult to treat and recurrences are common. OBJECTIVES: To describe the epidemiological and mycological aspects of cases of chromoblastomycosis and its clinical forms in the state of Pará, Brazil. METHODS: Mycological exams (direct mycological examinations, culture and microculture) were performed and a clinical/epidemiological evaluation was made of 65 patients receiving care at the Dermatology Department of the Federal University of Pará between 2000 and 2007. The clinical classification proposed by Carrión in 1950 was used in this study. RESULTS: The majority of the patients were male (93.8%), agricultural workers (89.2%) of 45 to 55 years of age, and the majority of lesions (55.4%) were of the verrucous type, located principally on the lower limbs (81.5%). In the majority of the cases investigated (61.5%), the infection had been present for a long time, with a mean duration of 11 years. Direct mycological examination was performed in 86.2% of the patients (n=56). Of these, 96.4% (n=54) tested positive. Culture and microculture were performed in vitro in 47 cases of those that tested positive at direct microscopy, results showing Fonsecaea pedrosoi to be the only agent present in this sample. CONCLUSION: This study highlighted the extent to which chromoblastomycosis still affects the quality of life of the local population, principally individuals working in agriculture. This is a chronic disease for which there is no effective treatment. The importance of continuing to investigate this disease should be emphasized, as further studies may lead to new clinical or epidemiological findings.

Chromoblastomycosis: a clinical and molecular study of 18 cases in Rio de Janeiro, Brazil

BACKGROUND

Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by dematiaceous fungi.

METHODS

We described epidemiological data, clinical presentation, and treatment of 18 cases of CBM diagnosed in Rio de Janeiro, Brazil. Diagnosis was obtained by mycological, histopathological findings demonstrating typical muriform cells with confirmation of isolated by DNA sequencing of the ribosomal internal transcribed spacer.

RESULTS

The majority of patients were male (72.2%) ranging from 39 to 83 years old, farm laborers and construction workers. The duration of disease varied from four months to 32 years. The most common presentations were verrucous form in ten (55.6%) patients, followed by tumoral in three (16.7%) patients, primarily of moderate (55.6%) and severe (38.9%) intensity. Lower (44.4%) and upper limbs (33.3%) were the most affected sites. Fonsecaea pedrosoi isolated from 14 (77.8%), and Cladophialophora carrionii isolated from one case (5.6%). Fifteen patients (83.3%) were treated. Six patients (40%) received oral itraconazole 200-400 mg/day, five patients (33.3%) received oral itraconazole 200-400 mg/day combined with fluconazole 200 mg/day, and four (26.7%) patients were submitted to surgery. The duration of therapy varied from 12 to 48 months. Cure rate was 80% (12/15). No relapse was observed after two years of follow-up.

CONCLUSIONS

Success was due to attending a center with specialized clinical care, laboratory support, and pharmaceutical care.

Pseudoepitheliomatous hyperplasia: a review

Pseudoepitheliomatous hyperplasia (PEH) is a benign condition, characterized by hyperplasia of the epidermis and adnexal epithelium, closely simulating squamous cell carcinoma. PEH may be present in a number of conditions characterized by prolonged inflammation and/or chronic infection, as well as in association with many cutaneous neoplasms. Herein, we review different inflammatory, infectious, and neoplastic skin diseases, in which florid epidermal hyperplasia is a prominent histopathologic feature, and introduce a systematic approach in the interpretation of PEH.

[Transepidermal elimination of parasites in Jorge Lobo's disease]

BACKGROUND

Few studies have focussed on the transepidermal elimination of parasites in Jorge Lobo's disease (lobomycosis).

OBJECTIVE

To identify the morphological features of the transepidermal elimination of parasites in lobomycosis.

METHODS

Sections were obtained from paraffin-embedded biopsy specimens of patients with lobomycosis and stained with hematoxylin-eosin for microscopic examination. Only the presence of parasites in epidermal structures was considered to constitute transepidermal elimination.

RESULTS

Forty biopsies from 37 patients were included in the study (31 males and 6 females). The mean age of patients was 51.03 years (range 29-80 years). Biopsies performed over a period of 37 years (1967-2003) were used, from which 511 sections were obtained (a mean of 12.77 sections per case; range 2-39 sections per case). Transepidermal elimination of parasites was found in 110/511 (21.52%) and was absent in 401/511 sections (78.48%) (p<0.0001). Features consistent with the phenomenon were found in 15/37 patients (40.5%) and were absent in 22/37 (59.5%) (p>0.05). Parasites in the epidermis were detected within hyperplastic infundibula, either connected in chains or as isolated units, associated or not with inflammatory cells.

CONCLUSION

Features consistent with transepidermal elimination of parasites were found in a statistically nonsignificant number of patients in the sample (p>0.05), suggesting that in Jorge Lobo's disease, this phenomenon invariably occurs through the infundibular epithelium. Future studies are required to evaluate the significance of this finding in the epidemiology of mycosis.

The cell wall fraction from Fonsecaea pedrosoi stimulates production of different profiles of cytokines and nitric oxide by murine peritoneal cells in vitro

Chromoblastomycosis is a chronic, suppurative and granulomatous mycosis whose main etiologic agent is the fungus Fonsecaea pedrosoi. The severity of chromoblastomycosis clinical manifestations correlates with the Th1 or Th2 immune response, and an efficient cellular immune response depends on the interaction between immune cells and the cell wall of the fungi, which is able to promote this activation. The objective of this study was to analyze the influence of cell wall fractions of Fonsecaea pedrosoi on the activation of peritoneal phagocytes obtained from mice. Our results revealed that after 4 h of inoculation with fungal cell wall components, there was a cell migration predominantly comprised of neutrophils followed, after 72 h, by migration of the macrophages. After 4 h, the F2 fraction caused increased production of nitric oxide in phagocytes, but this effect was not observed in the phagocytes after 72 h. The F1 fraction stimulated production of IL-12 in cells that migrated after 72 h, while the inactivated fungus and the F2 fraction led to production of IL-10. The F2 fraction decreased the rate of phagocytosis and increased the production of IL-10. Our results suggest that the F2 fraction and its components caused an important disruption of microbicidal mechanisms negatively modulating the immune response and favoring the persistence of the fungus.

[Chromomycosis in Guadeloupe]

BACKGROUND

Chromomycosis is a widespread subcutaneous fungal infection seen essentially in tropical and subtropical regions and transmitted via skin injury caused by the prickles of plants or infected wood splinters. It is prevalent throughout the West Indies including Guadeloupe, where its incidence is not well known.

PATIENTS AND METHODS

This retrospective and descriptive study concerns five histologically established cases of chromomycosis in Guadeloupe between 1995 and 2005. The five patients were diagnosed and treated at Pointe-à-Pitre University Teaching Hospital.

RESULTS

The study concerned four male patients and one female patient with an average age of 78 years; four were from the Basse-Terre district and one was from the Grande-Terre district. The most frequent clinical aspect was nodular or verrucous. The most common initial topography was the upper limbs. Fonsecaea pedrosoi was the only species identified. Diagnosis was confirmed by histopathology, which in all cases revealed sclerotic cells. Three patients underwent surgical treatment and two received medical treatment; only two patients were cured by 2005.

DISCUSSION

Our study confirms the presence of a source of chromomycosis in Guadeloupe, where Fonsecaea pedrosoi is clearly the best adapted species. It also highlights the difficulties of therapeutic care in tropical areas.

Lacaziose (doença de Jorge Lobo): revisão e atualização

Lacaziose ou doença de Jorge Lobo é micose crônica, granulomatosa, causada por implantação traumática do fungo Lacazia loboi - patógeno não cultivável até o presente - nos tecidos cutâneo e subcutâneo, manifestando-se clinicamente por lesões nodulares queloidianas predominantes, envolvendo sobretudo pavilhões auriculares, face, membros superiores e inferiores, e não comprometendo as mucosas. A maioria dos casos humanos está registrada em países da América do Sul. Entretanto, a enfermidade apresenta aspectos epidemiológicos destacados, como o aparecimento em tribo Caiabi, no Brasil Central e em mamíferos não humanos, golfinhos de duas espécies (Tursiops truncatus e Sotalia guianensis) capturados na costa da Flórida (EUA), na foz do rio Suriname, na costa de Santa Catarina (Brasil), no golfo de Gasconha (baía de Biscaia-Europa), com manifestações cutâneas e achados histopatológicos muito similares às encontradas no homem. O artigo objetiva abordar características do fungo e sua taxonomia, e aspectos históricos, ecoepidemiológicos, clínicos, imuno-histoquímicos, histopatológicos, ultra-estruturais e terapêuticos.

Biology and pathogenesis of Fonsecaea pedrosoi, the major etiologic agent of chromoblastomycosis

Fonsecaea pedrosoi is the principal etiologic agent of chromoblastomycosis, a fungal disease whose pathogenic events are poorly understood. Treatment of the disease presents poor effectiveness and serious side effects. The disease is epidemiologically important in several regions, which has stimulated studies focused on the biology and pathogenic potential of its major causative agent. In this review, we summarize the current knowledge on the biological aspects of F. pedrosoi, including cell differentiation and pathogenic mechanisms during the interaction of fungi with different hosts' elements.

Chromoblastomycosis

Chromoblastomycosis is a chronic subcutaneous mycotic infection caused by pigmented or dematiaceous saprophytic moulds ubiquitous in the environment. The most common etiologic agents are Fonsecaea pedrosoi and Cladophialophora carrionii, both of which can be isolated from plant debris. The infection usually follows traumatic inoculation through penetrating thorn or splinter wounds. The fungal agents develop as small clusters of cells known as muriform bodies. Several months after the injury, painless papules or nodules appear in the affected area progressing to scaly and verrucose plaques. Direct examinations of skin scrapings or histopathologic study demonstrates the typical muriform bodies. Microbiologic culture is necessary for the correct determination of the etiologic agent. Itraconazole is the treatment of choice, often in combination with surgery. Even so, results are often unsatisfactory as patients present late to medical services because of lack of funds and the fact that the disease usually affects the main family earner.

Inhibition of Nitric Oxide Production by Macrophages in Chromoblastomycosis: A Role for Fonsecaea pedrosoi Melanin

Chromoblastomycosis is a chronic and progressive deep mycosis that is usually found in tropical and subtropical areas. Fonsecaea pedrosoi is considered its most frequent etiologic agent and causes a typical granulomatous inflammatory response, whose degree reflects the immune status of the host. Since macrophages play a fundamental role in the control of the infection, this study aimed at investigating the production of oxygen reactive specimens, the phagocytic capacity and the production of nitric oxide (NO) by macrophages employing in vitro assays and an in vivo model of chromoblastomycosis. Our results demonstrated that, during the infection, peritoneal macrophages show an increased phagocytic capacity and H2O2 production, but also a reduced ability to produce NO. Moreover, F. pedrosoi stimulated H2O2 production in vitro but not the synthesis of NO. The incubation of IFNgamma and LPS-stimulated macrophages with melanin, obtained from the fungus, inhibited NO production. Examination of the liver and spleen of infected animals, at day 30 or 60 following inoculation, showed a progressive increase in the number and size of granulomas, indicating that macrophages are properly mobilized and activated. Our data suggest that the inability of the host to clear F. pedrosoi, leading to a chronic disease, is due, at least in part, to the inhibition of NO synthesis by macrophages by fungus-produced melanin.

Vinyl adhesive tape also effective for direct microscopy diagnosis of chromomycosis, lobomycosis, and paracoccidioidomycosis

Among the existing techniques for direct microscopy diagnosis in mycology, vinyl adhesive tape (VAT) preparations have proved their usefulness for Malassezia spp., Candida spp., and dermatophyte superficial infections. The collection and identification of fungal agents can be performed easily by the VAT technique, as demonstrated in this work, for the setting of some deep-seated cutaneous mycoses, where infectious agents can be observed in the horny layer of the epidermis in transepidermal elimination events. Preliminary results obtained in a series of 19 cases (chromomycosis, 12; lobomycosis, 5; paracoccidioidomycosis, 2) yielded positive results in 17 (89.47%). Failures for proper microscopic diagnosis detection happened in just 2 cases, 1 for chromomycosis and 1 for paracoccidioidomycosis. These results, although encouraging, were obtained from a relatively small patient population sample. Thus, the authors recommend further tests using this direct microscopy technique in a larger number of patients to validate these preliminary results and to explore its sensitivity in cases of small lesions.

Antigen distribution and antigen-presenting cells in skin biopsies of human chromoblastomycosis

BACKGROUND

Chromoblastomycosis is a chronic, suppurative, granulomatous mycosis usually confined to skin and subcutaneous tissues. The host defense mechanisms in chromoblastomycosis have not been extensively investigated. The purpose of the present study was to determine the distribution and pathways of the fungal antigen(s) and the possible role of the different immunocompetent cells in antigen processing in skin lesions.

METHODS

The distribution of Fonsecaea pedrosoi antigen(s) in human skin was studied in 18 biopsies from 14 patients with chromoblastomycosis. A purified polyclonal immune serum raised in rabbits against metabolic antigen(s) of F. pedrosoi was used to detect yeast antigen(s) by immunohistochemical procedures. Double immunolabeling was performed with yeast antigen(s) and Langerhans' cells [labeled with anti-S100 protein monoclonal antibody (MoAb)], yeast antigen(s) and factor XIIIa+ dermal dendrocytes (immunolabeled with anti-factor XIIIa polyclonal antibody), and yeast antigen(s) and macrophages (labeled with CD 68 monoclonal antibody).

RESULTS

The F. pedrosoi antigen(s) accumulated in the skin macrophages and, in a few instances, in factor XIIIa+ dendrocytes and Langerhans' cells.

CONCLUSIONS

The data obtained suggest that chiefly macrophages, also Langerhans' cells and factor XIIIa+ dermal dendrocytes, function as antigen-presenting cells in chromoblastomycosis.

The cell-mediated immune reaction in the cutaneous lesion of chromoblastomycosis and their correlation with different clinical forms of the disease

Chromoblastomycosis is a fungal infection caused by dematiaceous fungi inducing skin lesions of difficult treatment and of frequent recurrence. The objective of the present investigation was to characterize cell-mediated tissue reactions in the skin in cases of Chromoblastomycosis using histopathology and immunocytochemistry methods and to correlate them with different clinical forms of Chromoblastomycosis. Biopsies from 19 patients were stained with HE and Giemsa, and serial sections were immunohistochemically stained using CD45RO, CD20, CD4, CD8, CD68, CD1a, CD34, IL4, IL10, TNF-alpha and IFN-gamma antibodies. A quantitative and semiquantitative analysis of the cell subsets and cytokines in the inflammatory infiltrates was performed by counting ten high-power fields (400x). The cutaneous lesion presented as verrucous plaque (n = 15) or erythematous atrophic plaque (n = 4). We observed two types of tissue reaction: A) a granulomatous reaction with a suppurative granuloma with several fungi cells in the cutaneous lesion presenting as verrucous plaque; B) a granulomatous reaction with a tuberculoid granuloma with few fungi cells in the cutaneous lesion presenting as atrophic plaque. The data obtained suggest that patients with lesion presented as verrucous plaque have a type Th2 immunological response, while patients with lesion presented as erythematous atrophic plaque have a type Th1 response.

Chromoblastomycosis: clinical and mycologic experience of 51 cases

This is a study of 51 cases of chromoblastomycosis detected in a 17-year period, all of which were clinically and mycologically proven by direct examinations, cultures and biopsies. The therapeutic results of the various treatments used are reported. Most cases were males (36 of 51; 70%), the mean age was 35 years and farmers predominated (74%); the most frequent lesions were in the lower limbs (54%). Major clinical presentations were nodular (41%) and verrucous (26%). The principal aetiologic agent isolated was Fonsecaea pedrosoi (90%). Overall results of the various treatments were as follows: 31% were cured, 57% improved and 12% failed. The best results were obtained with cryosurgery for small lesions, with itraconazole for large ones, and in some cases the combination of both treatments.

Chromoblastomycosis: a retrospective study of 325 cases on Amazonic Region (Brazil)

A retrospective study of 325 cases of chromoblastomycosis diagnosed in the last 55 years in the Amazon region was carried out by the main Mycology services of the state of Pará, Brazil (Department of Tropical Pathology--UFPA and Mycology Department of the Evandro Chagas Institute/FNS). The data obtained showed that: (a) the main age group affected by the diseases range from 41 to 70 years-old, (b) 86.1% of the patients were agricultural-workers, (c) 93.2% of them were males and (d) 80.7% showed lesions on the lower limbs (feet and legs). The diagnosis of 62% of the cases was confirmed by laboratory studies considering the tissue form in histopathological analysis. In 24% of patients (78 cases), the etiological agent was isolated and identified through culture. Fonsecaea pedrosoi was present in 77 cases and Phialophora verucosa in only one case.

The in vitro susceptibility of Fonsecaea pedrosoi to activated macrophages

Light and electron microscopy were used to analyze in vitro the interaction of Fonsecaea pedrosoi with in vivo activated-macrophages. Adherence of the fungi to the surface of activated macrophages triggers the respiratory burst as revealed by reduction of nitroblue tetrazolium. Transmission electron microscopy revealed NAD(PO)H-oxidase activity in the portions of the macrophage plasma of membrane that were in contact with the fungus as well as within phagocytic vacuoles. Activated macrophages failed to kill ingested fungi, but they showed a fungistatic activity delaying germ tube and hyphae formation.