ABSTRACT
Emmonsia crescens is known as an environmental pathogen causing adiaspiromycosis in small rodents. As the generic name Emmonsia is no longer available for this species, its taxonomic position is re-evaluated. The intraspecific variation of Emmonsia crescens was analyzed using molecular, morphological, and physiological data, and the relationship between frequency of adiaspiromycosis and body temperature of host animals was explored. A North American and a pan-global lineage could be discerned, each with subclusters at low genetic distance. European strains produced the classical type of very large adiaspores, while in the North American lineage adiaspores relatively small, resembling the broad-based budding cells of Blastomyces. Members of the closely related genus Emergomyces may exhibit large, broad-based in addition to small, narrow-based budding cells. We conclude that the morphology of the pathogenic phase in these fungi differs gradationally between species and even populations, and is therefore less suitable as a diagnostic criterion for generic delimitation. Two Emmonsia species are reclassified in Emergomyces.
Subject(s)
Body Temperature , Chrysosporium , Lung Diseases, Fungal , Animals , Chrysosporium/classification , Chrysosporium/pathogenicity , Lung Diseases, Fungal/veterinaryABSTRACT
Lophophyton gallinae (Microsporum gallinae) is a zoophilic fungus that causes ringworm in chickens and related species, and occasionally in humans. There are 45 human cases worldwide including a Japanese case from Okinawa in 2009. After the finding of the human L. gallinae case, 793 chickens in Japan, including 293 from the mainland and 500 from the Nansei Island areas, were investigated to determine the prevalence of dermatophytes and their related fungal species. The survey was carried out from December 2008 to March 2013. Various dermatophytes and related fungal species were isolated from the studied chickens, with a prevalence of 24.6%. In total, 224 dermatophytes and related species were isolated in the survey. The most commonly isolated species included, in descending order of frequency, Arthroderma multifidum, Aphanoascus terreus, and Chrysosporium spp. Ar. multifidum and Ap. terreus have no record of pathogenicity, and the present isolates of Chrysosporium spp. were not matched to pathogenic Chrysosporium spp. based on the ITS rDNA sequences. Interestingly, an L. gallinae isolate was detected in a male 10-month-old shamo (fighting cock) from the main island. Furthermore, one strain of Arthroderma simii was also isolated as the second record in Japan following that from an imported chimpanzee. Although L. gallinae and Ar. simii are likely to be endemic in our country, the transmission of dermatophytosis from chickens to humans is unlikely to occur because of the reduced chances for citizens to come in contact with chickens due to various factors.
Subject(s)
Arthrodermataceae/isolation & purification , Arthrodermataceae/pathogenicity , Chickens/microbiology , Chrysosporium/isolation & purification , Chrysosporium/pathogenicity , Dermatomycoses/microbiology , Dermatomycoses/veterinary , Microsporum/isolation & purification , Microsporum/pathogenicity , Zoonoses/microbiology , Animals , Arthrodermataceae/genetics , Chrysosporium/genetics , DNA, Fungal/genetics , DNA, Ribosomal/genetics , Dermatomycoses/transmission , Humans , Japan , Microsporum/genetics , Pan troglodytes/microbiology , Sequence Analysis, DNAABSTRACT
The degree of antagonism exercised by fungi on geohelminth development varies according to the morphological alterations caused by different fungal species. Saprophytic fungi may exert ovicidal or ovistatic effects. The aim of this study was to apply scanning electron microscopy (SEM) to observe the action of two soil saprophytic species of Chrysosporium (C. indicum and C. keratinophylum) on Toxocara canis eggs. The fungal strains to be tested were incubated for 28 days at 28 °C in 2% water agar with a suspension of unembryonated T. canis eggs. A suspension of T. canis eggs in 2% water agar was used as control group. The assay was done in triplicate for each fungus and the control group. SEM observations were performed on the 4th, 7th, 14th, 21st, and 28th day after inoculation. The effect of the fungi on eggs was evaluated in accordance with the alterations observed on the surface and the changes in the normal characteristics of the eggs. Hyphae around the eggs, appresoria penetrating the shell and changes in the typical egg membrane were observed in this assay. Type 3 effect (alterations that occur both in the embryo and the shell, and hyphal penetration of the eggs) was the prevalent effect. SEM allowed us to observe clearly the morphological alterations in T. canis eggs due to the effect of C. indicum and C. keratinophylum. Both saprophytic species of Chrysosporium alter the egg structure and alterations increase as exposure increases.
El grado de antagonismo ejercido por los hongos sobre el desarrollo de los geohelmintos depende de la especie fúngica y las alteraciones morfológicas que causan. Los hongos saprofitos pueden tener efecto ovicida u ovistático sobre los huevos. El objetivo fue aplicar la microscopía electrónica de barrido (MEB) para observar la acción de 2 especies de Chrysosporium (C. indicum y C. keratinophylum) saprofitas de suelos, sobre huevos de Toxocara canis.Las especies a ensayar se sembraron en agar agua al 2% con una suspensión de huevos no embri-onados de T. canis y se incubaron 28 días a 28 °C. Como grupo control se utilizó una suspensión de huevos de T. canis en agar agua al 2%. El ensayo se realizó por triplicado para cada hongo y el grupo control. Las observaciones con MEB se realizaron a los 4, 7, 14, 21 y 28 días de incubación. La acción de los hongos se evaluó según las alteraciones en la superficie y los cambios en las características normales de los huevos. En este ensayo se observaron: hifas rodeando los huevos, appresorios penetrando la cubierta y cambios en la membrana característica del huevo, prevaleciendo el efecto tipo 3 (alteraciones que se producen tanto en el embrión como en la cubierta y penetración de hifas al interior de los huevos). La aplicación de la MEB permitió observar claramente que las 2 especies de Chrysosporium saprofitas de suelos, afectan el normal desarrollo de los huevos de T. canis, alteran su estructura y las alteraciones aumentan con el tiempo de exposición.
Subject(s)
Animals , Chrysosporium , Toxocara canis , Ovum , Soil , Soil Microbiology , Chrysosporium/pathogenicity , Toxocara canis/microbiology , FungiABSTRACT
The degree of antagonism exercised by fungi on geohelminth development varies according to the morphological alterations caused by different fungal species. Saprophytic fungi may exert ovicidal or ovistatic effects. The aim of this study was to apply scanning electron microscopy (SEM) to observe the action of two soil saprophytic species of Chrysosporium (C. indicum and C. keratinophylum) on Toxocara canis eggs. The fungal strains to be tested were incubated for 28 days at 28°C in 2% water agar with a suspension of unembryonated T. canis eggs. A suspension of T. canis eggs in 2% water agar was used as control group. The assay was done in triplicate for each fungus and the control group. SEM observations were performed on the 4th, 7th, 14th, 21st, and 28th day after inoculation. The effect of the fungi on eggs was evaluated in accordance with the alterations observed on the surface and the changes in the normal characteristics of the eggs. Hyphae around the eggs, appresoria penetrating the shell and changes in the typical egg membrane were observed in this assay. Type 3 effect (alterations that occur both in the embryo and the shell, and hyphal penetration of the eggs) was the prevalent effect. SEM allowed us to observe clearly the morphological alterations in T. canis eggs due to the effect of C. indicum and C. keratinophylum. Both saprophytic species of Chrysosporium alter the egg structure and alterations increase as exposure increases.
Subject(s)
Chrysosporium , Toxocara canis , Animals , Chrysosporium/pathogenicity , Fungi , Ovum , Soil , Soil Microbiology , Toxocara canis/microbiologyABSTRACT
Over the last 50 years, newly described species of Emmonsia-like fungi have been implicated globally as sources of systemic human mycosis (emmonsiosis). Their ability to convert into yeast-like cells capable of replication and extra-pulmonary dissemination during the course of infection differentiates them from classical Emmonsia species. Immunocompromised patients are at highest risk of emmonsiosis and exhibit high mortality rates. In order to investigate the molecular basis for pathogenicity of the newly described Emmonsia species, genomic sequencing and comparative genomic analyses of Emmonsia sp. 5z489, which was isolated from a non-deliberately immunosuppressed diabetic patient in China and represents a novel seventh isolate of Emmonsia-like fungi, was performed. The genome size of 5z489 was 35.5 Mbp in length, which is ~5 Mbp larger than other Emmonsia strains. Further, 9,188 protein genes were predicted in the 5z489 genome and 16% of the assembly was identified as repetitive elements, which is the largest abundance in Emmonsia species. Phylogenetic analyses based on whole genome data classified 5z489 and CAC-2015a, another novel isolate, as members of the genus Emmonsia. Our analyses showed that divergences among Emmonsia occurred much earlier than other genera within the family Ajellomycetaceae, suggesting relatively distant evolutionary relationships among the genus. Through comparisons of Emmonsia species, we discovered significant pathogenicity characteristics within the genus as well as putative virulence factors that may play a role in the infection and pathogenicity of the novel Emmonsia strains. Moreover, our analyses revealed a novel distribution mode of DNA methylation patterns across the genome of 5z489, with >50% of methylated bases located in intergenic regions. These methylation patterns differ considerably from other reported fungi, where most methylation occurs in repetitive loci. It is unclear if this difference is related to physiological adaptations of new Emmonsia, but this question warrants further investigation. Overall, our analyses provide a framework from which to further study the evolutionary dynamics of Emmonsia strains and identity the underlying molecular mechanisms that determine the infectious and pathogenic potency of these fungal pathogens, and also provide insight into potential targets for therapeutic intervention of emmonsiosis and further research.
Subject(s)
Chrysosporium/genetics , Chrysosporium/pathogenicity , Genomics , China , Computational Biology , DNA, Fungal/chemistry , DNA, Fungal/genetics , Diabetes Complications , Genome, Fungal , Humans , Mycoses/microbiology , Phylogeny , Sequence Analysis, DNA , Virulence Factors/geneticsABSTRACT
Three closely related thermally dimorphic pathogens are causal agents of major fungal diseases affecting humans in the Americas: blastomycosis, histoplasmosis and paracoccidioidomycosis. Here we report the genome sequence and analysis of four strains of the etiological agent of blastomycosis, Blastomyces, and two species of the related genus Emmonsia, typically pathogens of small mammals. Compared to related species, Blastomyces genomes are highly expanded, with long, often sharply demarcated tracts of low GC-content sequence. These GC-poor isochore-like regions are enriched for gypsy elements, are variable in total size between isolates, and are least expanded in the avirulent B. dermatitidis strain ER-3 as compared with the virulent B. gilchristii strain SLH14081. The lack of similar regions in related species suggests these isochore-like regions originated recently in the ancestor of the Blastomyces lineage. While gene content is highly conserved between Blastomyces and related fungi, we identified changes in copy number of genes potentially involved in host interaction, including proteases and characterized antigens. In addition, we studied gene expression changes of B. dermatitidis during the interaction of the infectious yeast form with macrophages and in a mouse model. Both experiments highlight a strong antioxidant defense response in Blastomyces, and upregulation of dioxygenases in vivo suggests that dioxide produced by antioxidants may be further utilized for amino acid metabolism. We identify a number of functional categories upregulated exclusively in vivo, such as secreted proteins, zinc acquisition proteins, and cysteine and tryptophan metabolism, which may include critical virulence factors missed before in in vitro studies. Across the dimorphic fungi, loss of certain zinc acquisition genes and differences in amino acid metabolism suggest unique adaptations of Blastomyces to its host environment. These results reveal the dynamics of genome evolution and of factors contributing to virulence in Blastomyces.
Subject(s)
Blastomyces/genetics , Chrysosporium/genetics , Genome, Fungal , Transcriptome/genetics , Animals , Blastomyces/pathogenicity , Blastomycosis/genetics , Blastomycosis/microbiology , Chrysosporium/pathogenicity , Histoplasmosis/genetics , Histoplasmosis/microbiology , Humans , Macrophages/microbiology , Mice , Paracoccidioidomycosis/genetics , Paracoccidioidomycosis/microbiologyABSTRACT
Emmonsia pasteuriana is a thermally dimorphic fungus identified in very few human cases. Here, we report a case of a 43-year-old male renal transplant patient from China presenting with multiple painful skin eruptions on his head, nose and left thigh, later accompanied by respiratory failure. Histopathology of the biopsy collected from the left thigh upper ulcer and occipital nodule both demonstrated chronic inflammation with granuloma formation and yeast-like elements. Emmonsia pasteuriana was cultured from two biopsy specimens and their identity was confirmed by sequencing of the rDNA internal transcribed spacer. The patient in intensive care showed marked clinical improvement with antifungal treatment.
Subject(s)
Chrysosporium , Dermatomycoses/etiology , Kidney Transplantation/adverse effects , Adult , Antifungal Agents/therapeutic use , China , Chrysosporium/genetics , Chrysosporium/isolation & purification , Chrysosporium/pathogenicity , Dermatomycoses/drug therapy , Dermatomycoses/pathology , Humans , Male , Respiratory Insufficiency/etiologyABSTRACT
Adiaspiromycosis is a pulmonary infection caused by the soil fungi, Emmonsia crescens and E. parva. It primarily affects small mammals and can range from an asymptomatic condition to fatal disseminated disease. We detected a granuloma containing fungal spherules, which were morphologically consistent with the adiaspores of E. crescens in the lungs of a female Hokkaido sika deer. This is the first reported case of adiaspiromycosis involving a cervid in the world.
Subject(s)
Chrysosporium/pathogenicity , Deer/microbiology , Lung Diseases, Fungal/veterinary , Animals , Female , Japan , Lung/microbiology , Lung/pathology , Lung Diseases, Fungal/microbiology , Lung Diseases, Fungal/pathology , Spores, Fungal/ultrastructureABSTRACT
BACKGROUND: The genus emmonsia contains three species that are associated with human disease. Emmonsia crescens and Emmonsia parva are the agents that cause adiaspiromycosis, and one human case of Emmonsia pasteuriana infection has been described. We report a fungal pathogen within the genus emmonsia that is most closely related to E. pasteuriana in human immunodeficiency virus (HIV)-infected adults in South Africa. METHODS: Between July 2008 and July 2011, we conducted enhanced surveillance to identify the cause of systemic, dimorphic fungal infections in patients presenting to Groote Schuur Hospital and other hospitals affiliated with the University of Cape Town, Cape Town, South Africa. DNA sequencing was used to identify pathogenic fungi. RESULTS: A total of 24 cases of dimorphic fungal infection were diagnosed, 13 of which were caused by an emmonsia species. All 13 patients were HIV-infected, with a median CD4+ T-cell count of 16 cells per cubic millimeter (interquartile range, 10 to 44), and all had evidence of disseminated fungal disease. Three patients died soon after presentation, but the others had a good response to a variety of antifungal agents and antiretroviral therapy. Phylogenetic analysis of five genes (LSU, ITS1-2, and the genes encoding actin, ß-tubulin, and intein PRP8) revealed that this fungus belongs in the genus emmonsia and is most closely related to E. pasteuriana. CONCLUSIONS: The findings suggest that these isolates of an emmonsia species represent a new species of dimorphic fungus that is pathogenic to humans. The species appears to be an important cause of infections in Cape Town.
Subject(s)
AIDS-Related Opportunistic Infections/microbiology , Mycoses/microbiology , Adult , Chrysosporium/classification , Chrysosporium/genetics , Chrysosporium/isolation & purification , Chrysosporium/pathogenicity , Female , HIV Infections/complications , Humans , Male , Phylogeny , South AfricaSubject(s)
Chrysosporium/pathogenicity , Crotalus/microbiology , Mycoses/veterinary , Animals , Chrysosporium/isolation & purification , Communicable Diseases, Emerging/microbiology , Communicable Diseases, Emerging/pathology , Communicable Diseases, Emerging/veterinary , Illinois , Mycoses/microbiology , Mycoses/pathologyABSTRACT
A adiaspiromicose é uma doença fúngica sistêmica que acomete usualmente roedores e raramente atinge o homem. É causada pelo fungo Emmonsia crescens e ocorre após a inalação da forma contagiante (conídios). Embora estas formas não se multipliquem nem se disseminem no organismo humano, induzem uma reação inflamatória crônica granulomatosa de padrão miliar que pode levar a falência respiratória e morte. Apresentamos aqui um caso de adiaspiromicose pulmonar humana em paciente imunocompetente que exibia infiltrado intersticial pulmonar difuso ao exame de imagem e fora diagnosticado mediante biópsia pulmonar.
Adiaspiromycosis is a systemic fungal disease that usually affects rodents and rarely infects humans. It is caused by the fungus Emmonsia crescens and occurs after inhalation of its contagious form (conidia). Although these forms neither multiply nor spread in the human body, they cause a chronic granulomatous inflammatory reaction of miliary pattern, which may lead to respiratory failure and death. In this study we present a case of human pulmonary adiaspiromycosis in an immunocompetent patient that showed a diffuse pulmonary interstitial infiltrate diagnosed by pulmonary biopsy.
Subject(s)
Humans , Male , Middle Aged , Chrysosporium/pathogenicity , Lung Diseases, Fungal/diagnosis , Lung Diseases, Fungal/pathology , Biopsy , Diagnostic Imaging , Spores, Fungal/pathogenicity , Lung Diseases, Fungal , TomographyABSTRACT
We conducted an epidemiologic investigation of an outbreak of ocular disease among children to determine whether the disease was linked to Emmonsia sp., a rarely-reported fungus and an agent of adiaspiromycosis. Using an unmatched case-control study design, we compared case-patients with asymptomatic controls randomly selected from the population. Scleral biopsies were analyzed microscopically. Of 5,084 children examined, 99 case-patients were identified; mean age (+1 SD) was 11.0 +/- 4.4 years. Symptoms included photophobia (57%), ocular pain (42%), and blurred vision (40%). In the multivariate analysis, risk factors included diving in the Araguaia River (odds ratio 5.2; 95% confidence interval 2.4-12.0). Microscopy identified foreign bodies consistent with adiaconidia. This outbreak probably resulted from foreign-body-type reactions to adiaspiromycosis conidia after initial irritation caused by conjunctival contact with spicules of sponges in the river. Symptomatic children responded to corticosteroid treatment. Adiaspiromycosis is a preventable cause of ocular disease in the Amazon region.
Subject(s)
Chrysosporium/pathogenicity , Communicable Diseases, Emerging/epidemiology , Conjunctivitis/epidemiology , Eye Infections, Fungal/epidemiology , Porifera/microbiology , Uveitis, Anterior/epidemiology , Adolescent , Animals , Brazil/epidemiology , Case-Control Studies , Child , Child, Preschool , Chrysosporium/isolation & purification , Communicable Diseases, Emerging/diagnosis , Communicable Diseases, Emerging/microbiology , Conjunctivitis/diagnosis , Conjunctivitis/microbiology , Disease Outbreaks , Eye Infections, Fungal/diagnosis , Eye Infections, Fungal/microbiology , Female , Fresh Water , Humans , Infant , Male , Uveitis, Anterior/diagnosis , Uveitis, Anterior/microbiology , Young AdultABSTRACT
Se presenta un caso de sinusitis fúngica invasiva en un paciente con inmunodeficiencia adquirida, algo atípico tanto en su evolución como en lo referente al agente causal. Se trata de Chrysosporium tropicum, hongo rara vez filiado hasta la fecha como causante de infecciones nasosinusales. Se ha revisado la literatura y se ha constatado que hay un solo caso publicado con un cuadro clínico similar al presentado. Destacamos la importancia de un diagnóstico precoz al igual que el tratamiento para la reducción de la morbimortalidad
An invasive sinusal mycosis in a patient with acquired immunodeficiency is reported. The clinical course and causal agent (Chrysosporium tropicum) were both rather atypical. This fungus has been seldom isolated as a cause of nasosinusal infections. Just one more case like this is found when literature is reviewed. We emphasize importance of early diagnosis and treatment to reduce morbi-mortality
Subject(s)
Humans , Aged , Male , Mycoses/microbiology , Paranasal Sinus Diseases/microbiology , Chrysosporium/pathogenicity , AIDS-Related Opportunistic Infections/diagnosisABSTRACT
Emmonsia crescens, a dimorphic fungus of the order Onygenales, is primarily a pathogen of lower animals and rarely humans. Inhaled conidia of E. crescens fail to germinate in the lungs, and instead simply enlarge in lung tissue to become giant adiaspores. We present here the case of fatal Emmonsia crescens infection in a wild-caught British water vole (Arvicola terrestris). Histopathological examination of the animal, which died in captivity, revealed a multifocally extensive granulomatous reaction containing oval adiaspores scattered irregularly throughout the lungs. Mycological examination of fungus cultured from lung tissue and PCR amplification and sequencing of rDNA gene fragments of the cultured organism confirmed the diagnosis of massive infection by E. crescens.
Subject(s)
Arvicolinae/microbiology , Chrysosporium/pathogenicity , Lung Diseases, Fungal/veterinary , Mycoses/veterinary , Animals , Chrysosporium/genetics , Chrysosporium/isolation & purification , Chrysosporium/physiology , England , Fatal Outcome , Female , Lung/microbiology , Lung Diseases, Fungal/microbiology , Mycoses/diagnosis , Mycoses/microbiology , Spores, Fungal/isolation & purificationABSTRACT
Veiled chameleons (Chamaeleo calyptratus) were experimentally challenged with the fungus Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Chameleons were exposed to conidia in their captive environment, or were inoculated by direct application of a conidial suspension inoculum on intact and on abraded skin. The CANV induced lesions in all experimental groups and was recovered from infected animals, fulfilling Koch's postulates and confirming that it may act as a primary fungal pathogen in this species of reptile. A breach in cutaneous integrity, as simulated by mild scarification, increased the risk of infection but was not required for the CANV to express pathogenicity. Initial hyphae proliferation occurred in the outer epidermal stratum corneum, with subsequent invasion of the deeper epidermal strata and dermis. A spectrum of lesions was observed ranging from liquefactive necrosis of the epidermis to granulomatous inflammation in the dermis. CANV dermatomycosis appears to be contagious and can readily spread within a reptile collection, either directly through contact with infective arthroconidia or indirectly via fomites. Dense tufts of arthroconidiating hyphae were demonstrated histologically on the skin surface of many animals that developed dermatomycosis, and these arthroconidia may act as infective propagules involved in the transfer of disease between reptiles.
Subject(s)
Chrysosporium/pathogenicity , Dermatomycoses/veterinary , Lizards/microbiology , Animals , Dermatomycoses/microbiology , Dermatomycoses/pathology , Histocytochemistry , Skin/microbiology , Skin/pathology , VirulenceSubject(s)
Chrysosporium/pathogenicity , Horse Diseases/diagnosis , Lung Diseases, Fungal/veterinary , Animals , Base Sequence , Chrysosporium/genetics , DNA, Fungal , Diagnosis, Differential , Fatal Outcome , Horse Diseases/microbiology , Horses , Immunohistochemistry/veterinary , Lung/microbiology , Lung/pathology , Lung Diseases, Fungal/diagnosis , Lung Diseases, Fungal/microbiology , Male , Molecular Sequence Data , Polymerase Chain ReactionABSTRACT
Relatam-se casos de adiaspiromicose pulmonar em homens brancos de 29 e 54 anos, lavradores, com sintomas "gripais" e achados radiológicos sugestivos de doença granulomatosa intersticial. Biópsias transbrônquicas e transtoracoscópicas foram realizadas. A funçäo pulmonar foi avaliada por espirometria. Um paciente usou cetoconazol. Enfatizam-se possibilidades de confusäo diagnóstica na adiaspiromicose pulmonar