Sporothrix schenckii and sporotrichosis

Zoonotic sporotrichosis in humans and domestic cats: Profile of notifications and spatio-temporal distribution in Southeastern Brazil between 2017 and 2023

The research addresses zoonotic sporotrichosis in Brazil, particularly caused by Sporothrix brasiliensis, highlighting its epidemiological severity. Transmission occurs through contact with sick animals, especially felines, and diagnosis in humans is challenging due to the low fungal load in the lesions. The study analyzed data from Information System for Notifiable Diseases (SINAN) and Zoonosis Surveillance Unit (UVZ) from January 2017 to March 2023, carried out in Contagem, Minas Gerais. Geospatial tools and statistical analysis revealed a significant increase in cases, peaking in 2021 for felines and 2022 for humans. The geospatial analysis highlighted areas of higher incidence, suggesting a correlation between human and feline populations. The research contributes to the understanding of sporotrichosis in Contagem, emphasizing the importance of integrated approaches for surveillance and control strategies, aiming to mitigate impacts on the local community.

Outbreak of Feline Sporotrichosis with Zoonotic Potential in the Seventh Health District of Maceió-AL

Sporotrichosis is a mycosis with zoonotic potential caused by species of Sporothrix. Once thought rare in northeastern Brazil, the disease has recently been spreading, leading to an emergency health issue. In this paper, we describe an outbreak of feline sporotrichosis in the Seventh Health District of Maceió-AL. We collected samples from 23 domiciled and non-domiciled felines without regard for age, breed, sex, and neutering state. Skin samples were analyzed cytologically under a light microscope and seeded onto Sabouraud dextrose agar at 25 °C for from 15 to 30 days. Fifteen of the twenty-three cats with suspected skin lesions were positive for Sporothrix spp. on either cytological or microbiological evaluation. Most of the infected cats were male, young adults, non-neutered, with free access to external areas, and living in environments with poor sanitation, a high population density, and an accumulation of garbage and organic matter. Three owners were bitten or scratched by infected cats and subsequently developed suspicious cutaneous lesions suggestive of sporotrichosis. The epidemiological features of feline sporotrichosis in the outbreaks of Maceió seemed to share similarities with the data obtained from outbreaks in current hyperendemic areas. Identifying geographical sites of infection and providing compulsory notification of the disease is essential for avoiding an epidemic in Alagoas.

Clinical factors associated with systemic sporotrichosis in Brazil

BACKGROUND

Systemic sporotrichosis occurs when organs, other than subcutaneous tissues and lymph nodes, are infected. Interestingly, systemic sporotrichosis in apparently immunocompetent individuals is increasing in Brazil, but data on clinical manifestations and risk factors are scarce. Most of the existing data on such condition relate to people living with HIV. We aimed to study the risk factors associated with systemic sporotrichosis among HIV-negative and HIV-positive patients.

METHODS

We performed a retrospective cross-sectional study with 80 patients from Brazil, diagnosed between 2014 and 2021. The association between disease classification, clinical presentation and risk factors were analysed by logistic regression.

RESULTS

Of the 80 patients, 29 (36.3%) presented with systemic sporotrichosis. All HIV-positive patients developed the systemic form, with increased mortality (p = .002). Alcohol ingestion (p = .009) and diabetes (p = .010) were associated with systemic disease. Alcohol ingestion seemed to favour pulmonary infection (p = .013) and, diabetes favoured osteoarticular (p = .009) and ocular involvement (p = .033). The occurrence of fever (p = .001) and weight loss (p = .006) were significantly associated with systemic sporotrichosis, while meningeal involvement (p = .001) increased mortality risk. Nine (11.3%) patients died from sporotrichosis. The presence of fungal structures in the mycological examination of the patients' lesions were associated with the systemic form (p = .017) and death (p = .002).

CONCLUSION

Our study points to the factors that drive systemic sporotrichosis other than HIV, such as alcohol ingestion and diabetes. Considering the high number of patients presenting severe sporotrichosis, the recognising these factors may contribute to timely diagnosis and proper treatment.

Phenotypic and genotypic characterization of Colombian clinical isolates of Sporothrix spp

INTRODUCTION

For over a century, Sporothrix schenckii was considered the sole species responsible for sporotrichosis. In 2007, scientific community confirmed the disease could be caused by various Sporothrix species. These species differed in their virulence factors and their antifungal sensitivity.

OBJECTIVE

This study aims to characterize 42 Colombian clinical isolates of Sporothrix spp. phenotypically and genotypically.

MATERIAL AND METHODS

Forty-two clinical isolates were characterized using phenotypic methods. It involved various culture media to determine their growth range at different temperatures and to assess the type and distribution of pigment and colony texture. Microscopic morphology was evaluated through microcultures, as well as the conidia diameter, type of sporulation, and morphology. Additionally, the assimilation of carbohydrates was selected as a physiological trait for species identification. Genotyping of 40 isolates was performed through partial amplification of the calmodulin gene, followed by sequence analysis.

RESULTS

Molecular studies enabled the identification of 32 isolates of S. schenckii and 8 isolates of S. globosa. The combination of phenotypic and genotypic methods eased these species characterizations and the recognition keys development based on parameters such as growth diameter at 25 and 30 ºC, colony texture (membranous or velvety) on potato dextrose agar, and microscopic morphology with predominance of pigmented triangular, elongated oval globose, or subglobose conidia.

CONCLUSIONS

Confirmation of the phenotypic characteristics and molecular analysis is crucial for identifying Sporothrix species and determining adequate treatment. This study represents the first phenotypical and genotypical characterization of clinical isolates of Sporothrix spp. reported in Colombia.

Sporotrichosis: A Review of a Neglected Disease in the Last 50 Years in Brazil

Sporotrichosis is caused by fungi belonging to the genus Sporothrix, which saprophytically are found in plants and organic matter. However, cats are highly susceptible to contamination with fungal spores and, when they become sick, they can transmit it to other animals and to man. The objective of this study is to carry out a systematic review on the emergency, diagnosis, clinical symptoms, therapeutics, and control of zoonotic sporotrichosis. Published data covering the last 50 years using a combination of keywords were selected to answer the question: Why has the zoonotic sporotrichosis been a neglected disease up to now? A total of 135 studies were included in this review. The studies emphasize that in recent decades, Brazil has experienced an unprecedented zoonotic outbreak of sporotrichosis. Advances on the genus Sporothrix allowed one to associate thermotolerance, capacity for melanin synthesis, potential for adhesion to tissue macromolecules, ergosterol peroxide production, and expression of virulence proteins as tools for infection and invasion in S. brasiliensis, the main species involved, although cases with S. schenckii or S. lurei were also reported. Correct diagnosis, early treatment, basic educational measures that emphasize responsible ownership of animals and reproductive control programs for felines can contribute to the control of zoonosis.

Beyond Domestic Cats: Environmental Detection of Sporothrix brasiliensis DNA in a Hyperendemic Area of Sporotrichosis in Rio de Janeiro State, Brazil

In Brazil, sporotrichosis has transitioned from a rural to urban disease, driven by a shift in the initiation of infection from the accidental inoculation of organic matter to the traumatic implantation of the fungus by cats. Since the emergence of zoonotic sporotrichosis caused by Sporothrix brasiliensis, investigations have largely ignored the environmental habitat of the pathogen due to its association with domestic cats. Therefore, we investigated 18 environmental samples collected from rural areas of two cities where zoonotic sporotrichosis is endemic, but where domestic cats are scarce. We utilized traditional culture methods, and samples were also examined with two molecular methods used for the clinical diagnosis of sporotrichosis: a nested-PCR targeting the ITS region and a species-specific PCR targeting the calmodulin gene. No Sporothrix colonies were identified by traditional culture methods. However, the nested-PCR and the species-specific PCR for S. brasiliensis were positive for 18 and 5 samples, respectively. Sequencing revealed that positive results with the nested-PCR were due to non-specific amplification of other Ophiostomatales DNA, rather than Sporothrix spp. Three of the five amplicons from the species-specific PCR were suitable for sequencing and confirmed the presence of S. brasiliensis DNA. Hence, we confirmed that S. brasiliensis, as with other Sporothrix species, has an environmental habitat. Our findings underscore the challenges of nested-PCR for Sporothrix environmental studies and highlight that sequencing must follow PCR protocols to definitively identify Sporothrix spp. in environmental samples.

Sporotrichosis Caused by Non-Wild Type Sporothrix brasiliensis Strains

The zoonotic transmission of sporotrichosis due to Sporothrix brasiliensis occurs largely in Rio de Janeiro state, Brazil since the 1990´s. Most patients infected with S. brasiliensis respond well to itraconazole or terbinafine. However, a few patients have a slow response or do not respond to the treatment and develop a chronic infection. The aim of this study was to analyze strains of S. brasiliensis against five different drugs to determine minimal inhibitory concentration distributions, to identify non-wild type strains to any drug evaluated and the clinical aspects of infections caused by them. This study evaluated 100 Sporothrix spp. strains obtained from 1999 to 2018 from the Evandro Chagas National Institute of Infectious Diseases, Fiocruz, which were identified through a polymerase chain reaction using specific primers for species identification. Two-fold serial dilutions of stock solutions of amphotericin B, itraconazole, posaconazole, ketoconazole and terbinafine prepared in dimethyl sulfoxide were performed to obtain working concentrations of antifungal drugs ranging from 0.015 to 8.0 mg/L. The broth microdilution reference method was performed according the M38-A2 CLSI guideline. All strains were identified as S. brasiliensis and thirteen were classified as non-wild type, two of them against different drugs. Non-wild type strains were identified throughout the entire study period. Patients infected by non-wild type strains presented prolonged treatment times, needed increased antifungal doses than those described in the literature and one of them presented a permanent sequel. In addition, three of them, with immunosuppression, died from sporotrichosis. Despite the broad use of antifungal drugs in hyperendemic areas of sporotrichosis, an emergence of non-wild type strains did not occur. The results of in vitro antifungal susceptibility tests should guide sporotrichosis therapy, especially in immunosuppressed patients.

Keratinocyte Response to Infection with Sporothrix schenckii

Sporotrichosis is a subacute, or chronic mycosis caused by traumatic inoculation of material contaminated with the fungus Sporothrix schenckii which is part of the Sporothrix spp. complex. The infection is limited to the skin, although its progression to more severe systemic or disseminated forms remains possible. Skin is the tissue that comes into contact with Sporothrix first, and the role of various cell lines has been described with regard to infection control. However, there is little information on the response of keratinocytes. In this study, we used the human keratinocyte cell line (HaCaT) and evaluated different aspects of infection from modifications in the cytoskeleton to the expression of molecules of the innate response during infection with conidia and yeast cells of Sporothrix schenckii. We found that during infection with both phases of the fungus, alterations of the actin cytoskeleton, formation of membrane protuberances, and loss of stress fibers were induced. We also observed an overexpression of the surface receptors MR, TLR6, CR3 and TLR2. Cytokine analysis showed that both phases of the fungus induced the production of elevated levels of the chemokines MCP-1 and IL-8, and proinflammatory cytokines IFN-α, IFN-γ and IL-6. In contrast, TNF-α production was significant only with conidial infection. In late post-infection, cytokine production was observed with immunoregulatory activity, IL-10, and growth factors, G-CSF and GM-CSF. In conclusion, infection of keratinocytes with conidia and yeast cells of Sporothrix schenckii induces an inflammatory response and rearrangements of the cytoskeleton.

Clinical and Epidemiological Characteristics of Sporotrichosis in a Reference Center of Uruguay

Background: Sporotrichosis is a fungal implantation disease of subacute/ chronic course caused by species of the dimorphic fungus Sporothrix spp. This infection usually develops after traumatic inoculation of contaminated soil, plants or organic material contaminated by Sporothrix spp. conidia into skin or mucosa. The objective of this work is to contribute to the knowledge of sporotrichosis in Uruguay by providing a report of a series of cases diagnosed in a reference center. Methods: We conducted a retrospective, observational, descriptive and cross-sectional study of cases of sporotrichosis diagnosed in the last 38 years. Results: In the period analyzed, 157 cases of sporotrichosis were diagnosed, 152 of those corresponded to male patients. The most frequent clinical presentation was nodular lymphatic in 120 patients. In relation to epidemiological antecedents, 128 patients had been scratched by armadillos during hunting. Conclusions: Sporotrichosis in Uruguay is a sporadic disease with a clear seasonal pattern related to particular social practices, such as hunting armadillos. Related to this practice, the affectation is greater in males and in young adults.

Virulence Factors of Sporothrix schenckii

Sporothrix schenckii is one of the etiological agents of sporotrichosis. In this review, we discuss the virulence factors that have been proven to participate in the S. schenckii-host interaction. Among these known factors, we can find cell wall glycoproteins, adhesins, melanin, extracellular vesicles, and dimorphism. Furthermore, the morphological transition of S. schenckii in response to environmental conditions such as pH and temperature represents a means by which the fungus is able to establish mycosis in mammals. One of the key features in the development of sporotrichosis is the adhesion of the fungus to the host extracellular matrix. This event represents the first step to developing the mycosis, which involves adhesins such as the glycoproteins Gp70, Hsp60, and Pap1, which play a key role during the infection. The production of melanin helps the fungus to survive longer in the tissues and to neutralize or diminish many of the host’s attacks, which is why it is also considered a key factor in pathogenesis. Today, the study of human fungal pathogens’ virulence factors is a thriving area of research. Although we know some of the virulence factors in S. schenckii, much remains to be understood about the complex process of sporotrichosis development and the factors involved during the infection.

Clinical, Epidemiological, and Epizootic Features of Sporothrix brasiliensis in Espírito Santo, Brazil

We verified the clinical-epidemiological, microbiological, and molecular aspects of feline sporotrichosis in Espírito Santo, Brazil, as well as demonstrated the degree of reliability of the cytopathological examination in diagnosis, when compared to fungal culture. From March 2019 to April 2020, 154 suspicious cats were evaluated by collecting data and biological samples. The Cohen's kappa coefficient and the Chi-square independence defined the degree of agreement and the accuracy parameters, respectively. The interobserver agreement was high (Kappa coefficient = 0.96). Sensitivity, specificity, predictive (positive and negative), and accuracy values were 95.0, 97.0, 99.1, 84.2, and 95.5%, respectively. All isolates evaluated were identified as Sporothrix brasiliensis by species-specific PCR. A digital image bank (Padlet) was created with different types of clinical forms and positive slide profiles. We concluded that the cytopathological technique used demonstrated a high degree of reliability. We report an overwhelming occurrence of S. brasiliensis during epizooties in ES.

Sporotrichosis: hyperendemic by zoonotic transmission, with atypical presentations, hypersensitivity reactions and greater severity

In recent decades, an alarming increase in the number of sporotrichosis cases has been reported in southern and southeastern Brazil, especially in the state of Rio de Janeiro, has been considered a long-term hyperendemic condition associated with feline transmission. According to phenotypic classifications, the Sporothrix species recovered from cats were classified as S. brasiliensis in 96.5% of the studied cases. This finding has also been demonstrated in humans, which confirms the zoonotic transmission associated with this predominant species in Brazil. The zoonotic transmission of the fungus and its important virulence in the context of the hyperendemic situation in Rio de Janeiro have changed the approach to the disease, which in its classic form was restricted to certain professional groups and very specific regions in the Brazilian territory, into a public health challenge of scientific interest. Its atypical manifestations and hypersensitivity reactions are increasingly frequent, constituting a new sporotrichosis aspect, which deserves attention from the medical community, as well as from other health professionals.

The Historical Burden of Sporotrichosis in Brazil: a Systematic Review of Cases Reported from 1907 to 2020

Sporotrichosis is a cosmopolitan subcutaneous mycosis caused by Sporothrix species. Recently, this mycosis has gained notoriety due to the appearance of new endemic areas, recognition of new pathogenic species, changes in epidemiology, occurrence of outbreaks, and increasing numbers of cases. The purpose of this study is to analyze the peculiarities of sporotrichosis cases in Brazil since its first report in the country until 2020. In this work, ecological, epidemiological, clinical, and laboratorial characteristics were compiled. A systematic review of human sporotrichosis diagnosed in Brazil and published up to December 2020 was performed on PubMed/MEDLINE, SciELO, Web of Science, and LILACS databases. Furthermore, animal sporotrichosis and environmental isolation of Sporothrix spp. in Brazil were also evaluated. The study included 230 papers, resulting in 10,400 human patients. Their ages ranged from 5 months to 92 years old and 55.98% were female. The lymphocutaneous form was predominant (56.14%), but systemic involvement was also notably reported (14.34%), especially in the lungs. Besides, hypersensitivity manifestations (4.55%) were described. Most patients had the diagnosis confirmed by isolation of Sporothrix spp., mainly from skin samples. Sporothrix brasiliensis was the major agent identified. HIV infection, cardiovascular diseases, and diabetes were the most common comorbidities. Cure rate was 85.83%. Concerning animal sporotrichosis, 8538 cases were reported, mostly in cats (90.77%). Moreover, 13 Sporothrix spp. environmental strains were reported. This review highlights the burden of the emergent zoonotic sporotrichosis in Brazil, reinforcing the importance of "One Health" based actions to help controlling this disease.

Sporotrichosis: A Clinicopathologic Study of 89 Consecutive Cases, Literature Review, and New Insights About Their Differential Diagnosis

BACKGROUND

Sporotrichosis is the most common and least severe of deep mycoses. This disease has varied clinic presentation as well as several differential diagnosis.

METHODS

A cross-sectional and retrospective, individually based, observational study, based on records from the dermatopathology service of a university hospital in Brazil. A total of 175 patients were identified with clinical suspicion of sporotrichosis, from 2009 to 2017. Statistical analysis using prevalence ratios was conducted to characterize the clinicopathologic and epidemiological aspects.

RESULTS

The disease was suspected in 175 patients given the clinical presentation. Of these, 86 cases (49.14%) were sporotrichosis, 39 (22.29%) chronic granulomatous inflammatory processes of unidentified etiology, and 5 squamous cell carcinomas (2.86%). The majority of cases (52 or 60.46%) occurred in the upper limbs. A total of 40 samples presented a suppurative chronic granulomatous inflammatory process (46.51%). Only 5 samples (12.50%) showed positive staining (periodic-Schiff acid or GROCOTT).

CONCLUSIONS

The sporotrichosis cases underwent both cumulative and linear growth, especially in the group above 60 years. Squamous cell carcinomas appeared several times as a misdiagnosis of sporotrichosis by dermatologists, so it should be considered as an important differential diagnose due to the current context of skin cancers.

Sporotrichosis in Mexico

Sporotrichosis is an endemic mycosis caused by the species of the Sporothrix genus, and it is considered one of the most frequent subcutaneous mycoses in Mexico. This mycosis has become a relevant fungal infection in the last two decades. Today, much is known of its epidemiology and distribution, and its taxonomy has undergone revisions. New clinical species have been identified and classified through molecular tools, and they now include Sporothrix schenckii sensu stricto, Sporothrix brasiliensis, Sporothrix globosa, and Sporothrix luriei. In this article, we present a systematic review of sporotrichosis in Mexico that analyzes its epidemiology, geographic distribution, and diagnosis. The results show that the most common clinical presentation of sporotrichosis in Mexico is the lymphocutaneous form, with a higher incidence in the 0-15 age range, mainly in males, and for which trauma with plants is the most frequent source of infection. In Mexico, the laboratory diagnosis of sporotrichosis is mainly carried out using conventional methods, but in recent years, several researchers have used molecular methods to identify the Sporothrix species. The treatment of choice depends mainly on the clinical form of the disease, the host's immunological status, and the species of Sporothrix involved. Despite the significance of this mycosis in Mexico, public information about sporotrichosis is scarce, and it is not considered reportable according to Mexico's epidemiological national system, the "Sistema Nacional de Vigilancia Epidemiológica." Due to the lack of data in Mexico regarding the epidemiology of this disease, we present a systematic review of sporotrichosis in Mexico, between 1914 and 2019, that analyzes its epidemiology, geographic distribution, and diagnosis.

Guideline for the management of feline sporotrichosis caused by Sporothrix brasiliensis and literature revision

We herein present a Brazilian guideline for the management of feline sporotrichosis, a mycosis caused by Sporothrix brasiliensis. This guideline is an effort of a national technical group organized by the Working Group on Sporothrix and Sporotrichosis of the International Society for Human and Animal Mycology (ISHAM). This publication intends to provide information on clinical-epidemiological aspects of this zoonosis, as well as a literature revision. Moreover, it gives some practical information on diagnosis and treatment of feline sporotrichosis. It also contains information that can be helpful for the prevention and control of S. brasiliensis transmission.

Primary conjunctival sporotrichosis in three cats from Northeastern Brazil

INTRODUCTION

Classically, sporotrichosis occurs as a chronic granulomatous lymphocutaneous infection. The extracutaneous form is uncommon and may affect the eye without cutaneous involvement. The most frequent form of ocular sporotrichosis reported in humans is a granulomatous conjunctivitis. There are no previous reports on primary ocular sporotrichosis in cats.

PROCEDURES

Three mixed breed cats rescued from shelters were referred by the veterinarian for ophthalmic evaluation with a complaint of conjunctivitis nonresponsive to treatment with no evidence of skin disease or systemic disease. Complete ophthalmic examination, conjunctival cytology, and microbiological analysis were performed.

RESULTS

Ophthalmic examinations revealed epiphora, purulent ocular discharge, conjunctival hyperemia, and a mass in the palpebral conjunctiva. Conjunctival cytology revealed segmented and degenerated neutrophils, conjunctival epithelial cells, and an abundant number of round and oval cells compatible with Sporothrix spp. Microbiological culture was performed and confirmed the presence of fungi from the Sporothrix schenckii complex. All animals were treated with oral itraconazole; two animals received topical itraconazole in association with oral treatment. Case 1 was refractory to treatment, and iodate potassium was combined with itraconazole therapy without resolution at the time of this publication. Cases 2 and 3 had complete resolution of conjunctival lesions with four months of oral and topical itraconazole therapy.

CONCLUSION

Conjunctival sporotrichosis should be considered as a differential diagnosis of conjunctivitis in cats from endemic regions. Conjunctival cytology is an important tool that can aid early diagnosis.

Molecular epidemiology of Sporothrix schenkii isolates in Malaysia

Sporothrix schenkii is a dimorphic fungus that causes infections in both humans and animals. We report on 25 S. schenkii isolates collected in 2017 from humans and cats clinically diagnosed with sporotrichosis, in Malaysia. These isolates were phenotypically identified as S. schenkii sensu lato and further defined as S. schenckii sensu stricto based on partial calmodulin gene sequence. Isolates from both humans and cats were genotypically identical but displayed phenotypic variation. Phylogenetic analyses based on partial calmodulin sequence showed that the Malaysian isolates clustered with global S. schenkii sensu stricto strains, in particular, of the AFLP type E. This analysis also revealed that partial calmodulin sequence alone was sufficient for classifying global S. schenckii sensu stricto strains into their respective AFLP types, from A to E. The genetically conserved S. schenkii sensu stricto species isolated from humans and cats is suggestive of a clonal strain present in Malaysia. To the best of our knowledge, this is the first report on molecular identification of Sporothrix schenkii strains from human infections in Malaysia. Further studies are required in order to elucidate the clonal nature of Malaysian S. schenkii isolates. Our findings indicate the presence of a predominant S. schenkii genotype in the environment, causing infections in both cats and humans in Malaysia.

Immunoreactive cutaneous sporotrichosis

Sporothrix spp. infection can occur through the inoculation of the organism in the skin through direct contact with the soil (sapronotic infection), through contact with animals, such as infected cats and dogs (zoonotic infection), or less frequently via inhalation. With a subacute or chronic evolution, approximately 80% of patients affected by the disease present with the lymphocutaneous form; episodes associated with a hypersensitivity reaction are rare. The authors report the case of a 12-year-old child with immunoreactive sporotrichosis manifested clinically as erythema nodosum lesions in the lower limbs, associated with an ulcerated lesion in the left arm.

Bibliometric assessment and key messages of sporotrichosis research (1945-2018)

Background: Sporotrichosis has recently emerged as an important mycosis worldwide, with diverse transmission and epidemiologic profiles. For instance, in Brazil most cases are related to zoonotic transmission from naturally infected cats, and the majority of cases in China are due to external injury with environmental materials. Publications on sporotrichosis and on its etiologic agent may guide the direction of the research in this field. It can also define priorities for future studies. Methods: In this study, we evaluated the trends of global research in Sporothrix and sporotrichosis, based on publications records retrieved from Scopus and Web of Science databases for the period of 1945 to 2018. The overall productivity in the field, its geographical and temporal distribution, research themes, co-authorship networks, funding sources, and if audience and research findings are addressed in the abstracts. Results: A total of 4,007 unique publications involving 99 countries were retrieved, most of them published after 2000. Authors based on institutions from the United States of America and Brazil accounted for 57.4% of the publications. Brazil was the leading country in terms of research collaboration and networking, with co-authorship with 45 countries. The thematic mapping revealed a temporal shift from clinical to applied research. Despite the large number of countries publishing in this field, most of funded studies came from Brazil, Mexico, China, South Africa, or the United States of America. The analysis of content identified few specific public health recommendations for prevention, case-management, or research. Moreover, most papers do not have a clearly defined intended audience. Conclusion: As the research in this field is emerging in several countries, with the generation of a large amount of data, it is necessary that scientists strengthen efforts to translate the research results into practice to curb this neglected infection.

Bibliometric assessment and key messages of sporotrichosis research (1945-2018)

Background: Sporotrichosis has recently emerged as an important mycosis worldwide, with diverse transmission and epidemiologic profiles. For instance, in Brazil most cases are related to zoonotic transmission from naturally infected cats, and the majority of cases in China are due to external injury with environmental materials. Publications on sporotrichosis and on its etiologic agent may guide the direction of the research in this field. It can also define priorities for future studies.

Methods: In this study, we evaluated the trends of global research in Sporothrix and sporotrichosis, based on publications records retrieved from Scopus and Web of Science databases for the period of 1945 to 2018. The overall productivity in the field, its geographical and temporal distribution, research themes, co-authorship networks, funding sources, and if audience and research findings are addressed in the abstracts.

Results: A total of 4,007 unique publications involving 99 countries were retrieved, most of them published after 2000. Authors based on institutions from the United States of America and Brazil accounted for 57.4% of the publications. Brazil was the leading country in terms of research collaboration and networking, with co-authorship with 45 countries. The thematic mapping revealed a temporal shift from clinical to applied research. Despite the large number of countries publishing in this field, most of funded studies came from Brazil, Mexico, China, South Africa, or the United States of America. The analysis of content identified few specific public health recommendations for prevention, case-management, or research. Moreover, most papers do not have a clearly defined intended audience.

Conclusion: As the research in this field is emerging in several countries, with the generation of a large amount of data, it is necessary that scientists strengthen efforts to translate the research results into practice to curb this neglected infection.

A case of sporotrichosis infection mimicking pyoderma gangrenosum and the role of tissue culture in diagnosis: A case report

Sporotrichosis infections may cause cutaneous lesions mimicking other infectious or non-infectious causes such as pyoderma gangrenosum. We present a case of cutaneous sporotrichosis misdiagnosed as pyoderma gangrenosum and treated with immunosuppressants for 17 months leading to exacerbation and atypical morphology mimicking Histoplasma organisms on biopsy. Exclusion of infection prior to diagnosing pyoderma gangrenosum is important to prevent iatrogenic immunosuppression, demonstrating the challenges with application of the updated pyoderma gangrenosum diagnostic criteria.

Geographical distribution and ecological niche modeling of the etiological agents of human sporotrichosis in Venezuela

The geographical distribution and ecological niche of the two circulating species of the Sporothrix genus in Venezuela was established. For this, 68 isolates of Sporothrix spp. from patients of different regions of the country were analyzed. A molecular taxonomy analysis was conducted using a fragment of the calmodulin gene (CAL), and ITS regions, confirming the presence of S. schenckii (62%) and S. globosa (38%). Computational models of ecological niche for each species were obtained by the maximum entropy method using the MaxEnt software, which predicted the best environmental conditions for the presence of the two species. These models predict that the main variables influencing the presence of S. schenckii were altitude and annual mean temperature, while for S. globosa, the more influent variable was the land use, with 82% of S. globosa located at urban areas vs 56% for S. schenckii. The results here presented could contribute to understand the specific environmental factors that might modulate the occurrence of Sporothrix spp. as well as its transmission. To our knowledge, our analyses show for the first time Sporothrix spp.-specific ecological niche data, a valuable tool to promote evidence-based public health policymaking within endemic areas of sporotrichosis.

Seroepidemiological survey on sporotrichosis-infection in rural areas of the south of Minas Gerais State, Brazil

Sporotrichosis is a subcutaneous mycosis caused by traumatic inoculation into the skin by fungi species of the genus Sporothrix. The disease has different clinical manifestations (cutaneous, lymphocutaneous, and disseminated), and can also progress to a systemic infection. Despite having a worldwide distribution, sporotrichosis is most prevalent in tropical and subtropical countries. In Brazil, reports of the disease are higher frequent, where cases of the disease were found in Rio de Janeiro, Sao Paulo, Curitiba, Pernambuco, and Paraiba, among others. Certain groups of people may be more exposed to the causative agent of disease, such as residents of rural areas. Thus, this work aimed to carry out a seroepidemiological survey of the prevalence of sporotrichosis in four rural locations in the south of Minas Gerais State, Brazil. In this study, we used an indirect ELISA test in the survey on the prevalence of sporotrichosis. Data obtained in this study evaluated a population of 631 individuals and showed a prevalence of 44.69%. The distribution of seroprevalence of sporotrichosis with respect to age groups and gender showed no significant statistical difference. Thus, we found a high seroprevalence of sporotrichosis-infection in rural regions of southern Minas Gerais State, Brazil, with no difference in prevalence in relation to gender and age.

Systemic sporotrichosis in an alcoholic patient

A 44-year-old male patient presented with nodules that evolved with inflammation, following drainage of seropurulent secretion and ulceration. The patient had a 6 year-history of alcohol addiction and reported contact with cats. At the physical examination, the patient had skin-colored and erythematous nodules, and ulcers covered with thick, blackened crusts on the face, trunk and limbs. A culture of a nodule fluid revealed growth of Sporotrix sp. He also had pulmonary involvement and therefore the disease was classified as systemic sporotrichosis, a rare form that usually affect patients infected with HIV. Chronic alcohol abuse was considered the factor of immunosuppression for the patient.

Associated factors and spatial patterns of the epidemic sporotrichosis in a high density human populated area: A cross-sectional study from 2016 to 2018

An epidemiological characterization of human and feline sporotrichosis was carried out between 2016 and 2018, in a high density-populated area in Brazil. Professionals were trained to identify suspect cats and notify vets to interview the owners and collect swabs of the wounds from these animals. Mycological cultures were performed, and colonies identified as Sporothrix spp. Subsequently, data regarding the outcome from suspect animals were collected. Confirmed cases of human sporotrichosis (56) were also counted and analyzed for spatial distribution. 118 positive animals were observed. The prevalence of feline sporotrichosis was 8.36 ‰ (CI 95 %, 5.38-9.55 ‰). The odds for being positive in animals that lived only partially at home were 3.02 times greater than for those cats without access to the street (OR 3.02, CI 95 % 1,96-10,43). There was no statistically significant association between environmental variables and positive diagnosis, corroborating the hypothesis that direct transmission by infected cats plays a greater role in the occurrence and continuous outbreaks of sporotrichosis in Brazil. Among the positive animals, 61.90 % (CI 95 % 58.95-64.96) died, and they had an odds to die in the next six months 6.30 times greater than negative animals (p < 0.05, OR 6.30, CI 95 % 2,79-14,42). The case fatality rate was 55.08 % in cats (CI 95 % 49.20-51.15). The cause-specific death rate was 4.6 ‰ in cats (CI 95 % 3.4-6 ‰). Only 7.62 % (CI 95 % 7.12-8.16) positive cats were treated and cured. Among dead positive animals, 29.23 % were inappropriately discarded. In the study period 56 human cases were recorded in the Barreiro region. Regions with highest prevalence of feline sporotrichosis, had greater frequencies of both human and feline cases. This is the first report on the epidemic of sporotrichosis in Minas Gerais, Brazil. The free offer for treatment and veterinary care for these animals should be taken into consideration, as well as the collection and incineration of the dead ones, as measures of public health, followed by the guidance and care for the human patient.

Immunization with recombinant enolase of Sporothrix spp. (rSsEno) confers effective protection against sporotrichosis in mice

In recent years, research has focused on the immunoreactive components of the Sporothrix schenckii cell wall that can be relevant targets for preventive and therapeutic vaccines against sporotrichosis, an emergent worldwide mycosis. In a previous study, we identified a 47-kDa enolase as an immunodominant antigen in mice vaccinated with an adjuvanted mixture of S. schenckii cell wall proteins. Here, we sought to assess the protective potential of a Sporothrix spp. recombinant enolase (rSsEno) formulated with or without the adjuvant Montanide Pet-GelA (PGA) against the S. brasiliensis infection in mice. Mice that were immunized with rSsEno plus PGA showed increased antibody titters against rSsEno and increased median survival time when challenged with S. brasiliensis as compared with mice that had not been immunized or that were immunized with rSsEno alone. Immunization with rSsEno plus PGA induced a predominantly T-helper 1 cytokine pattern after in vitro stimulation of splenic cells with rSsEno: elevated levels of IFN-γ and IL-2, as well as of other cytokines involved in host defense against sporotrichosis, such as TNF-alpha, IL-6, and IL-4. Furthermore, we show for the first time the presence of enolase in the cell wall of both S. schenckii and S. brasiliensis. As a whole, our results suggest that enolase could be used as a potential antigenic target for vaccinal purposes against sporotrichosis.

Meningeal and multiorgan disseminated sporotrichosis: A case report and autopsy study

This case report presents a 36-year old man with a disseminated sporotrichosis who presented with seizures and crusted lesions all over the body. Imaging studies revealed acute ischemic brain event with haemorrhagic transformation in right frontal lobe. Skin biopsy showed Sporothrix schenckii. He was treated with standard amphotericin B. Despite therapy, he developed consciousness loss, multiorgan-failure and eventually expired. Necropsy findings showed renal, hepatic, splenic, prostate, testicles and meningeal/cerebral involvement.

Disseminated Sporotrichosis in a Liver Transplant Patient: A Case Report

Sporotrichosis is an infection caused by the fungus of the Sporothrix schenckii complex and can be particularly harmful in immunocompromised patients. We report the case of a 26-year-old male patient with a previous history of pulmonary infection who underwent a liver transplant for Budd-Chiari syndrome. After the procedure, he presented with persistent fever and leukocytosis. On the 13th post-operative day, he was diagnosed with thrombosis of the hepatic artery and underwent a second liver transplant 15 days after the first procedure. After the retransplant, he presented daily episodes of fever, even after the use of several antimicrobial, antiviral, and antifungal agents. A number of negative cultures from different sites were obtained. After an acute episode of mental confusion, the growth of S schenckii was observed in cultures from cerebrospinal fluid and ascites obtained from a diagnostic paracentesis. Treatment with amphotericin B was started but the patient died on the fourth day of antifungal treatment, from a massive gastrointestinal hemorrhage. We found no previous report in the literature of spontaneous dissemination of S schenckii to the abdominal cavity causing peritonitis.

Extracellular Vesicle-Mediated RNA Release in Histoplasma capsulatum

Eukaryotic cells, including fungi, release extracellular vesicles (EVs). These lipid bilayered compartments play essential roles in cellular communication and pathogenesis. EV composition is complex and includes proteins, glycans, pigments, and RNA. RNAs with putative roles in pathogenesis have been described in EVs produced by fungi. Here we describe the RNA content in EVs produced by the G186AR and G217B strains of Histoplasma capsulatum, an important human-pathogenic fungal pathogen. A total of 124 mRNAs were identified in both strains. In this set of RNA classes, 93 transcripts were enriched in EVs from the G217B strain, whereas 31 were enriched in EVs produced by the G186AR strain. This result suggests that there are important strain-specific properties in the mRNA composition of fungal EVs. We also identified short fragments (25 to 40 nucleotides in length) that were strain specific, with a greater number identified in EVs produced by the G217B strain. Remarkably, the most highly enriched processes were stress responses and translation. Half of these fragments aligned to the reverse strand of the transcript, suggesting the occurrence of microRNA (miRNA)-like molecules in fungal EVs. We also compared the transcriptome profiles of H. capsulatum with the RNA composition of EVs, and no correlation was observed. Taking the results together, our study provided information about the RNA molecules present in H. capsulatum EVs and about the differences in composition between the strains. In addition, we found no correlation between the most highly expressed transcripts in the cell and their presence in the EVs, reinforcing the idea that the RNAs were directed to the EVs by a regulated mechanism.IMPORTANCE Extracellular vesicles (EVs) play important roles in cellular communication and pathogenesis. The RNA molecules in EVs have been implicated in a variety of processes. EV-associated RNA classes have recently been described in pathogenic fungi; however, only a few reports of studies describing the RNAs in fungal EVs are available. Improved knowledge of EV-associated RNA will contribute to the understanding of their role during infection. In this study, we described the RNA content in EVs produced by two isolates of Histoplasma capsulatum Our results add this important pathogen to the current short list of fungal species with the ability to use EVs for the extracellular release of RNA.

Fast diagnosis of sporotrichosis caused by Sporothrix globosa, Sporothrix schenckii, and Sporothrix brasiliensis based on multiplex real-time PCR

The accurate diagnosis of sporotrichosis and identification at the species level are critical for public health and appropriate patient management. Compared with morphological identification methods, molecular diagnostic tests are rapid and have high sensitivity and standardized operating processes. Therefore, we designed a novel multiplex real-time polymerase chain reaction (PCR) method based on the calmodulin (CAL) gene for the identification of clinically relevant Sporothrix species: S. globosa, S. schenckii s. str., and S. brasiliensis. We evaluated the assay with clinical and spiked samples and assessed its diagnostic performance by comparing the results to those of culture and species-specific PCR. Thirty-three DNA templates were used to detect assay specificity, and three plasmids were constructed to create a standard curve and determine the limits of detection (LODs). For nucleic acid detection, the sensitivity and specificity reached 100%. The LODs were 10 copies, 10 copies and 100 copies for S. globosa, S. schenckii s. str and S. brasiliensis, respectively. For the clinical samples, the positive detection rates by culture, species-specific PCR and the multiplex real-time PCR assay were 87.9% (29/33), 39.4% (13/33), and 93.9% (31/33), respectively. For the spiked samples, the positive detection rates were both 100% for S. schenckii s. str and S. brasiliensis. Based on the above results, compared with culture and other molecular diagnosis methods, the novel multiplex real-time PCR assay is effective, fast, accurate, and highly sensitive. It has a lower reaction cost and lower sample volume requirements, can detect co-infections, and allows for standardized operation and easier interpretation of results. In the future, this assay could be developed into a commercial kit for the diagnosis and identification of S. globosa, S. schenckii s. str, and S. brasiliensis.

Sporotrichosis is a subacute or chronic infectious disease caused by dimorphic fungi of Sporothrix spp. The genus Sporothrix consists of several species with different geographic distributions, virulence, and antifungal susceptibilities, making species-level identification necessary. S. brasiliensis, S. globosa, S. schenckii s. str and S. luriei make up the “pathogenic clade” of the genus Sporothrix. Importantly, S. luriei has a low clinical-epidemiological impact within this genus. Therefore, we designed a novel multiplex real-time PCR method using fluorescent probes for the identification of S. globosa, S. schenckii s. str, and S. brasiliensis. We designed a pair of primers based on the conserved sequence of the calmodulin gene of Sporothrix spp. and probes with different fluorescent signals based on the divergent sequences of S. globosa, S. schenckii s. str and S. brasiliensis. Through the verification of nucleic acid, clinical and spiked sample detection, the multiplex real-time PCR could quickly and accurately identify the three clinically relevant species of Sporothrix spp. with high sensitivity. This new assay could be applied in epidemiology, clinical diagnosis, and experiments with sporotrichosis to control new outbreaks, reduce diagnostic and identification time, and improve test efficiency.

Ploidy Determination in the Pathogenic Fungus Sporothrix spp

The pathogenic clade of the Sporothrix genus comprises the etiological agents of sporotrichosis, a worldwide emergent disease. Despite the growing understanding of their successful pathogen traits, there is little information on genome sizes and ploidy within the genus. Therefore, in this work, we evaluated the ploidy of four species of the Sporothrix genus, specifically Sporothrix brasiliensis, Sporothrix schenckii, Sporothrix globosa, and Sporothrix pallida. Through cell cycle analysis of the yeast-phase cells, we showed that the DNA content of G0/G1 cells was similar to the genome size determined by whole genome sequencing. Moreover, ploidy of S. schenckii, S. brasiliensis, and S. pallida that was determined by allele composition using next-generation sequencing (NGS) data is consistent with monomorphic positions at each allele. These data show that the analyzed strains of Sporothrix are haploid, or at least aneuploid, thereby laying the foundation for the development of a molecular toolbox for Sporothrix spp.

Effects of metaperiodate and urea solutions on the serological diagnosis of human sporotrichosis using an indirect ELISA test

Sporotrichosis is an infection of the skin caused by traumatic inoculation of the fungus Sporothrix schenckii. Definitive diagnosis relies on direct visualization of the fungus or its isolation on culture medium, although both have low sensitivity. Alternatively, the detection of the antibody response offers a more rapid alternative for diagnosis. Although the available immunoassays possess good sensitivity and specificity, cross-reactivity is still a problem. This study aimed to evaluate the effect of sodium metaperiodate and 6 M urea solutions on the serological diagnosis of sporotrichosis using an enzyme-linked immunosorbent assay (ELISA) test. Ninety-six-well plates were sensitized with exoantigens from the yeast phase of S. schenckii. Sera of patients with confirmed sporotrichosis, sera of patients with paracoccidioidomycosis, and sera of individuals with a sporotrichin-negative skin test were tested. Two strategies were used; the first consisted of treating the antigen with sodium metaperiodate solution for different incubation times, and the second consisted of treating the serum with 6 M urea solution for different incubation times. ROC curve analysis revealed that the best discrimination parameters were obtained using 6 M urea solution incubated for 5 min and serum dilution at 1/600. The use of 6 M urea solution improves the performance of the ELISA test in the diagnosis of sporotrichosis.

Molecular Identification and Antifungal Susceptibility of Clinical Isolates of Sporothrix schenckii Complex in Medellin, Colombia

BACKGROUND

Sporotrichosis is a subcutaneous mycosis that affects humans and other animals. Infection prevails in tropical and subtropical countries. Until a few years ago, it was considered that two varieties of Sporothrix schenckii caused this mycosis, but by applying molecular taxonomic markers, it has been demonstrated that there are several cryptic species within S. schenckii complex which varies in susceptibility, virulence, and geographic distribution.

OBJECTIVE

This study aimed to identify the clinical isolates of Sporothrix spp. from patients with sporotrichosis in Medellin, Colombia, using two markers and to evaluate the in vitro susceptibility to itraconazole.

METHODS

Thirty-four clinical isolates of Sporothrix spp. from Colombia, three from Mexico, and one from Guatemala were identified through sequencing of the noncoding region ITS-1 + 5.8SDNAr + ITS-2 and of the fragment containing exons 3 and 4 of the β-tubulin gene. Clinical isolate sequences were compared with GenBank reference sequences using the BLASTN tool, and then, phylogenetic analysis was performed. Besides, the in vitro susceptibility to itraconazole was evaluated by determining the minimum inhibitory concentrations according to the CLSI M38-A2 method.

RESULTS

Clinical isolates were identified by morphology as Sporothrix spp. Using the molecular markers, ITS and β-tubulin, isolates were identified as S. schenckii sensu stricto (25) and Sporothrix globosa (13). Susceptibility to itraconazole was variable among clinical isolates.

CONCLUSION

This is the first scientific publication that identifies species that cause sporotrichosis in Colombia, along with the antifungal susceptibility to itraconazole.

Sporothrix spp. EVALUATION IN SOIL OF A HYPERENDENIC AREA FOR SPOROTRICHOSIS IN SOUTHERN BRAZIL

Abstract The increase in zoonotic sporotrichosis cases has become a public health problem in hyperendemic areas for the feline disease. Domestic cats involvement in this transmission and the continuous contact of these animals with soil suggest that the environment may be an essential source and/or reservoir of Sporothrix spp. Thus, the current study aimed to evaluate the presence of Sporothrix spp. in the soil of places where infected cats in Southern Brazil is present. In total, 101 soil samples were collected from the residence of cats with sporotrichosis, from regions around to these residences, and also from public places. These samples were processed using the direct plating technique being incubated at 25 °C for up to 15 days. Additionally, seventeen samples were also submitted to DNA extraction (NORGEN BIOTEK CORP® kit), PCR-specific and Nested-PCR technique. Although the presence of Sporothrix in soil has been undetected, by culture or molecular biology, this study does not reject the role of the environment in the triad of the infectious process (soil-animal-human). Thus, further studies are necessary for expanding the area of coverage, volume, type and method of sampling, and/or detection techniques.

A Case of Acute Granulomatous Conjunctivitis Caused by Cat-transmitted Sporothrix schenckii

In human, sporotrichosis infection commonly manifests as skin lesions through direct inoculation. It is rarely associated with ocular manifestation via a zoonotic transmission. We describe a young lady who presented with acute left eye granulomatous conjunctivitis who had a history of exposure to her sick cat diagnosed with sporotrichosis infection. Sporothrix schenckii was isolated from the culture of the excised conjunctival tissue. The patient recovered fully after six months of oral anti-fungal treatment. Clinicians should be aware of this new zoonotic infection transmitted by infected felines as it is reversible with timely diagnosis and initiation of anti-fungal therapy.

Surto de esporotricose felina na região metropolitana do Recife

RESUMO: A esporotricose é uma micose subcutânea, causada por um fungo dimórfico do complexo Sporothrix schenckii que acomete várias espécies, especialmente a felina, causando comprometimento local, disseminado ou sistêmico. Objetivou-se relatar a ocorrência de um surto de esporotricose felina na Região Metropolitana do Recife. Foram coletados suabes de úlceras cutâneas de felinos atendidos no Hospital Veterinário da Universidade Federal Rural de Pernambuco e em Clínicas Veterinárias particulares. O diagnóstico foi realizado por meio de exame citológico e cultura fúngica. Dos 115 casos suspeitos, 59 casos foram confirmados, número nunca registrado anteriormente no estado de Pernambuco. Os casos de esporotricose felina registrados têm demonstrado aspectos clínicos e epidemiológicos semelhantes aos ocorridos em outras regiões do país, caracterizando-se como uma doença predominantemente de machos jovens em idade reprodutiva e semi-domiciliados, de difícil tratamento e de rápida disseminação.

Immunity and Treatment of Sporotrichosis

Species of the Sporothrix complex are the etiological agents of sporotrichosis, an important subcutaneous mycosis with several clinical forms and an increasing incidence around the world that affects humans and other mammals. The immunological mechanisms involved in the prevention and control of this mycosis are not entirely understood. Many reports have suggested that cell-mediated immunity has an essential role in the development of the disease, being the primary response controlling it, while only recent data supports that the humoral response is essential for the appropriate control. This mycosis is a challenge for diagnosis since the culture and isolation of the organism are time-consuming and complicated; reasons that have led to the study of fungus antigenic molecules capable of generating a detectable humoral response. The treatment for this disease includes the use of several antifungal drugs like itraconazole, amphotericin B, caspofungin, fluconazole, and the combination between them among others such as the extract of Vismia guianensis.

Immunopathogenesis of Human Sporotrichosis: What We Already Know

Sporotrichosis is a subacute/chronic mycosis caused by dimorphic fungus of the genus Sporothrix. This mycosis may affect both human and domestic animals and in the last few years, the geographic dispersion and increase of sporotrichosis worldwide has been observed. The occurrence of cases related to scratching/bites of domestic felines have increased, characterizing the disease as predominantly a zoonosis. In humans, sporotrichosis mainly involves the cutaneous tegument of infected patients, but other tissues may also present the infection. The main forms of clinical presentation are lymphocutanous sporotrichosis (LC) and fixed sporotrichosis (F). Although less common, mucosal, cutaneous disseminated, and extracutaneous forms have also been described. Multiple factors from the fungus and host can play a role in driving the clinical evolution of sporotrichosis to benign or severe disease. In this review, we discuss the immunopathological aspects involved in human sporotrichosis. Putting together the two branches of knowledge—host immune response and fungal evading mechanisms—we may perceive new possibilities in understanding the fungus–host interaction in order to be in a position to go further in the control of sporotrichosis.

Generation of Sporothrix schenckii mutants expressing the green fluorescent protein suitable for the study of host-fungus interactions

Sporotrichosis is an infection caused by members of the Sporothrix genus, and among them, Sporothrix schenckii is one of the etiological agents. Both, the disease and the causative agent have gained interest in the recent years, because of the report of epidemic outbreaks, and the description of the disease transmission from animals to human beings. Despite the relevance of S. schenckii in the clinical field, there are basic aspects of its biology poorly explored. So far, Agrobacterium tumefaciens-mediated transformation has been reported as an alternative for genetic manipulation of this fungal pathogen. Here, we report the optimization of the transformation method and used this to generate insertional mutants that express the green fluorescent protein in S. schenckii. We obtained five mutant strains that showed mitotic stability and expression of the reporter gene. The strains displayed normal cell wall composition, and a similar ability to interact ex vivo with human monocytes and monocyte-derived macrophages. Moreover, the virulence in larvae of Galleria mellonella was similar to that obtained with the wild-type control strains. These data indicate that these fluorescent mutants with normal ability to interact with the host could be used in bioimaging to track the host-Sporothrix interaction in vivo.

In vitro susceptibility of Sporothrix brasiliensis: Comparison of yeast and mycelial phases

Sporothrix brasiliensis has emerged as an important cause of sporotrichosis, particularly associated with feline and zoonotic cases. Owing to the paucity of data on antifungal activity against this species, the present study aimed to evaluate the in vitro susceptibility of clinical isolates of S. brasiliensis in the mycelial and yeast phases to itraconazole (ITZ), terbinafine (TRB), and amphotericin B (AMB). Thirty-five isolates from an outbreak of feline sporotrichosis in Southern Brazil were used. All of them were assessed in the yeast and filamentous phases using the broth microdilution technique in accordance with the respective reference protocols M27-A3 and M38-A2 of the Clinical and Laboratory Standards Institute (CLSI). In our study, TRB was the most active antifungal against both the filamentous and yeast phases, showing GM of the MIC of 0.343 μg/ml and 0.127 μg/ml, respectively. In the yeast phase, the GM of the MIC for TRB was significantly lower than that for both ITZ (P = .009) and AMB (P < .001). However, in the filamentous phase, the GM of the MIC for TRB was significantly lower than that of AMB (P < .001), but not different from that of ITZ (P = .091). AMB was the antifungal with the highest GM of the MIC for both phases (1.486 μg/ml for the filamentous phase and 0.660 μg/ml for the yeast). Our results may contribute to a better understanding of antifungal susceptibility profiles of clinical isolates of S. brasiliensis in the mycelial and yeast phases in further studies.

Zoonotic Sporotrichosis Related to Cat Contact: First Case Report from Panama in Central America

A previously healthy 34-year-old man presented with a four-week-old upper arm injury that started with a cat scratch and progressed into painless erythematous nodular ascending lesions in the left upper limb. We made the diagnosis of sporotrichosis based on the epidemiological association of the contact with a cat and culture identification. Sporotrichosis is a mycosis implantation caused by the Sporothrix schenckii complex. We present the first Central American case of sporotrichosis associated with contact with a feline.

Cell walls of the dimorphic fungal pathogens Sporothrix schenckii and Sporothrix brasiliensis exhibit bilaminate structures and sloughing of extensive and intact layers

Sporotrichosis is a subcutaneous mycosis caused by pathogenic species of the Sporothrix genus. A new emerging species, Sporothrix brasiliensis, is related to cat-transmitted sporotrichosis and has severe clinical manifestations. The cell wall of pathogenic fungi is a unique structure and impacts directly on the host immune response. We reveal and compare the cell wall structures of Sporothrix schenckii and S. brasiliensis using high-pressure freezing electron microscopy to study the cell wall organization of both species. To analyze the components of the cell wall, we also used infrared and 13C and 1H NMR spectroscopy and the sugar composition was determined by quantitative high-performance anion-exchange chromatography. Our ultrastructural data revealed a bi-layered cell wall structure for both species, including an external microfibrillar layer and an inner electron-dense layer. The inner and outer layers of the S. brasiliensis cell wall were thicker than those of S. schenckii, correlating with an increase in the chitin and rhamnose contents. Moreover, the outer microfibrillar layer of the S. brasiliensis cell wall had longer microfibrils interconnecting yeast cells. Distinct from those of other dimorphic fungi, the cell wall of Sporothrix spp. lacked α-glucan component. Interestingly, glycogen α-particles were identified in the cytoplasm close to the cell wall and the plasma membrane. The cell wall structure as well as the presence of glycogen α-particles varied over time during cell culture. The structural differences observed in the cell wall of these Sporothrix species seemed to impact its uptake by monocyte-derived human macrophages. The data presented here show a unique cell wall structure of S. brasiliensis and S. schenckii during the yeast parasitic phase. A new cell wall model for Sporothrix spp. is therefore proposed that suggests that these fungi molt sheets of intact cell wall layers. This observation may have significant effects on localized and disseminated immunopathology.

Sporotrichosis: an update on epidemiology, etiopathogenesis, laboratory and clinical therapeutics

In the late 90's there was a change in both the route of transmission and the people at risk for sporotrichosis. This zoonotic cat-man alternative transmission route elicited changes in strategies to control the epidemic. There was a progressive increase in the number of cases involving especially children and the elderly. In addition to becoming hyperendemic, uncommon clinical pictures like immunoreactive clinical presentations or severe systemic cases have emerged. New species were identified and classified through molecular tools using more virulent clinical isolates, like S. brasiliensis, compared to the environmental isolates. Likewise, different species of Sporothrix have been associated with different geographic regions. The serological and molecular techniques are used as an auxiliary tool for the diagnosis and/or for species identification, although the isolation and the identification of Sporothrix spp. in clinical specimen is still the gold standard. Currently sporotrichosis epidemics requires the knowledge of the epidemiological-molecular profile to control the disease and the specific treatment. Itraconazole, potassium iodide, terfinafine, and amphotericin B are the available drugs in Brazil to treat sporotrichosis. The drug of choice, its posology, and treatment duration vary according to the clinical presentation, the Sporothrix species, and host immune status. New treatment choices, including a vaccine, are being developed; nevertheless, more clinical trials are required to confirm its efficacy.

The Sporothrix schenckii Gene Encoding for the Ribosomal Protein L6 Has Constitutive and Stable Expression and Works as an Endogenous Control in Gene Expression Analysis

Sporothrix schenckii is one of the causative agents of sporotrichosis, a worldwide-distributed mycosis that affects humans and other mammals. The interest in basic and clinical features of this organism has significantly increased in the last years, yet little progress in molecular aspects has been reported. Gene expression analysis is a set of powerful tools that helps to assess the cell response to changes in the extracellular environment, the genetic networks controlling metabolic pathways, and the adaptation to different growth conditions. Most of the quantitative methodologies used nowadays require data normalization, and this is achieved measuring the expression of endogenous control genes. Reference genes, whose expression is assumed to suffer minimal changes regardless the cell morphology, the stage of the cell cycle or the presence of harsh extracellular conditions are commonly used as controls in Northern blotting assays, microarrays, and semi-quantitative or quantitative RT-PCR. Since the biology of the organisms is usually species specific, it is difficult to find a reliable group of universal genes that can be used as controls for data normalization in experiments addressing the gene expression, regardless the taxonomic classification of the organism under study. Here, we compared the transcriptional stability of the genes encoding for elongation factor 1A, Tfc1, a protein involved in transcription initiation on Pol III promoters, ribosomal protein L6, histone H2A, β-actin, β-tubulin, glyceraldehyde 3-phosphate dehydrogenase, UAF30, the upstream activating factor 30, and the transcription initiation factor TFIID subunit 10, during the fungal growth in different culture media and cell morphologies. Our results indicated that only the gene encoding for the ribosomal protein L6 showed a stable and constant expression. Furthermore, it displayed not transcriptional changes when S. schenckii infected larvae of Galleria mellonella or interacted with immune cells. Therefore, this gene could be used as control for data normalization in expression assays. As a proof of concept, this gene was used to assess the expression of genes encoding for glycosidases involved in the protein N-linked glycosylation pathway, a histidine kinase whose expression is regulated during the fungal dimorphism, and a glycosidase that participates in sucrose assimilation.

Galactofuranose antigens, a target for diagnosis of fungal infections in humans

The use of biomarkers for the detection of fungal infections is of interest to complement histopathological and culture methods. Since the production of antibodies in immunocompromised patients is scarce, detection of a specific antigen could be effective for early diagnosis. D-Galactofuranose (Galf) is the antigenic epitope in glycoconjugates of several pathogenic fungi. Since Galf is not biosynthesized by mammals, it is an attractive candidate for diagnosis of infection. A monoclonal antibody that recognizes Galf is commercialized for detection of aspergillosis. The linkage of Galf in the natural glycans and the chemical structures of the synthesized Galf-containing oligosaccharides are described in this paper. The oligosaccharides could be used for the synthesis of artificial carbohydrate-based antigens, not enough exploited for diagnosis.

D-Galactofuranose (Galf) is the unit in polysaccharides and glycoconjugates of several pathogenic fungi that is recognized by the immune system. Since Galf is not synthesized by mammals, it is an attractive candidate for diagnosis of infection. Since the production of antibodies in immunocompromised patients is scarce, detection of a specific antigen could be effective for early diagnosis. An antibody that recognizes Galf is commercialized for the detection of aspergillosis. Chemically synthesized Galf-containing oligosaccharides, reviewed in this paper, could therefore be used for the synthesis of artificial carbohydrate-based antigens and in diagnosis.

Cutaneous Disseminated and Extracutaneous Sporotrichosis: Current Status of a Complex Disease

Sporotrichosis is an implantation or inoculation mycosis caused by species of Sporothrix schenckii complex; its main manifestations are limited to skin; however, cutaneous-disseminated, disseminated (visceral) and extracutaneous variants of sporotrichosis can be associated with immunosuppression, including HIV-AIDS, chronic alcoholism or more virulent strains. The most common extracutaneous form of sporotrichosis includes pulmonary, osteoarticular and meningeal. The laboratory diagnosis requires observing yeast forms and isolating the fungus; the two main causative agents are Sporothrix schenckii (ss) and Sporothrix brasiliensis. Antibody levels and species recognition by Polimerase Chain Reaction using biological samples or cultures are also useful. The treatment of choice for most cases is amphotericin B and subsequent itraconazole for maintenance therapy.