ABSTRACT
Adiaspiromycosis is a nontransmissible infectious pulmonary disease caused by the inhalation of propagules from fungal species belonging to the family Ajellomicetaceae, especially Emergomyces crescens. Adiaspiromycosis caused by E. crescens has been recorded in a broad number of species worldwide, with small burrowing mammals being considered the main hosts for this environmental pathogen. Only a handful of studies on adiaspiromycosis in European wildlife has been published to date. We assessed the occurrence of adiaspiromycosis in wild rodents (Murinae and Arvicolinae) from the central Spanish Pyrenees (NE Spain). The lungs of 302 mice and 46 voles were screened for the presence of adiaspores through histopathologic examination. Pulmonary adiaspiromycosis was recorded in 21.6% of all individuals (75/348), corresponding to 63/299 wood mice (Apodemus sylvaticus) and 12/40 bank voles (Myodes glareolus). Adiaspore burden varied highly between animals, with a mean of 0.19 spores/mm2 and a percentage of affected lung tissue ranging from <0.01% to >8%. These results show that the infection is present in wild rodents from the central Spanish Pyrenees. Although the impact of this infection on nonendangered species is potentially mild, it might contribute to genetic diversity loss in endangered species.
Subject(s)
Lung Diseases, Fungal , Rodent Diseases , Animals , Spain/epidemiology , Lung Diseases, Fungal/veterinary , Mammals , Murinae , Arvicolinae , Rodent Diseases/epidemiologyABSTRACT
A 65-year-old man with HIV sought treatment for fever, weight loss, and productive cough after returning to the United States from Liberia. Fungal cultures grew Emergomyces pasteurianus, and the patient's health improved after beginning voriconazole. We describe the clinical case and review the literature, treatment, and susceptibilities for E. pasteurianus.
Subject(s)
Mycoses , Onygenales , Humans , United States , Aged , Mycoses/microbiology , Liberia , VoriconazoleABSTRACT
Purpose of Review In this review, we provide an overview of emergomycosis from a clinical perspective and discuss the taxonomy and classification of the pathogens, epidemiology, pathophysiology of infection and mechanisms of pathogenesis, immunology, clinical manifestations, laboratory culture and diagnosis, molecular characterisation, therapy and prognosis. Recent Findings While Emergomyces pasteurianus is the most geographically-widespread species, Emergomyces africanus is endemic to Southern Africa and causes disseminated disease with cutaneous involvement primarily among patients with advanced human immunodeficiency virus (HIV) disease. Summary Emergomycosis, a disseminated clinical disease resulting from infection with dimorphic fungi in the genus Emergomyces, occurs primarily among immunocompromised patients. Further knowledge is needed on the pathophysiology, diagnosis and management of emergomycosis.
Subject(s)
HIV Infections , Mycoses , Humans , Mycoses/microbiologyABSTRACT
Emergomycosis is a recently described emerging opportunistic fungal infection among individuals living with HIV, in whom it is a cause of significant mortality and morbidity. This article retrospectively reports on a presumptive case of extensive cutaneous emergomycosis in a young immunocompromised patient from Lesotho. The histopathological features on skin biopsy were in keeping with emergomyces infection. The lesions responded to treatment with amphotericin B and oral fluconazole. Contribution: This case contributes to the existing evidence that as an emergent opportunistic infection, emergomycosis is possibly widespread in Africa but the true extend of the disease is not fully defined. This is further aggravated by the diagnostic difficulty as a result of limited resources in some areas in the region.
ABSTRACT
Lesions of adiaspiromycosis, a respiratory disease affecting wild animals, have been found mainly in dead mammals and free-living mammals captured for surveillance. No report has described an investigation of adiaspore formation progress in the lung. After establishing an experimental mouse model of intratracheal adiaspiromycosis infection with the causative agent Emmonsia crescens, we observed adiaspore development. The spores grew and reached a plateau of growth at 70 days post-infection. The median adiaspore diameter showed a plateau of around 40 µm. The characteristic three-layer cell-wall structure of adiaspores was observed in the lung at 70 days post-infection. We examined infection with a few spores, which revealed that adiaspores in the mouse lung progressed from intratracheal infection of at least 400 spores. Moreover, we developed adiaspores in vitro by culture in fetal bovine serum. Although most spores broke, some large spores were intact. They reached about 50 µm diameter. Thick cell walls and dense granules were found as common points between in vitro adiaspores and in vivo adiaspores. These models are expected to be useful for additional investigations of E. crescens adiaspores and adiaspiromycosis.
Subject(s)
Chrysosporium/physiology , Lung Diseases, Fungal/veterinary , Spores, Fungal/physiology , Animals , Chrysosporium/growth & development , Chrysosporium/ultrastructure , Disease Models, Animal , Lung Diseases, Fungal/microbiology , Male , Mice , Mice, Inbred C57BL , Microscopy/veterinary , Microscopy, Electron, Transmission/veterinary , Spores, Fungal/growth & development , Spores, Fungal/ultrastructureABSTRACT
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
Using specific primers based on the ribosomal operon, positive DNA amplification was obtained from lungs of 11/215 tested small burrowing animals, both terrestrial and aquatic, and including frozen (n = 4) and formalin-fixed paraffin-embedded (n = 7) samples. The main species detected in Europe in mice, otters and river rats was Emmonsia crescens. Two strains from otters and weasels were Blastomyces parvus. Two Australian wombats revealed the presence of a hitherto unknown species of the geophilic genus Emmonsiellopsis.
Subject(s)
Animals, Wild/microbiology , Chrysosporium/classification , Chrysosporium/genetics , Pathology, Molecular/methods , Animals , Blastomyces/classification , Blastomyces/genetics , Mice , Mustelidae/microbiology , RatsABSTRACT
In 2013, a novel thermally dimorphic fungal pathogen was described to cause disseminated disease among persons living with advanced HIV/AIDS in South Africa. Although the organism was initially described as an Emmonsia-like fungus, it is now known to belong to a new genus of thermally dimorphic fungi and was recently named Emergomyces africanus. There is considerable clinical and histopathological overlap between emergomycosis and histoplasmosis. This review addresses taxonomic, clinical, diagnostic, and therapeutic aspects of Es. africanus disease, a condition which has, to date, only been reported from southern Africa.
ABSTRACT
Adiaspiromycosis is a mycotic infection caused by thermally dimorphic fungi classified as Emmonsia parva and E. crescens (formerly Chrysosporium spp.) until recently, when new classifications were proposed. We document the pathologic findings in a severe case of adiaspiromycosis, with lymph node involvement, in a wild European rabbit ( Oryctolagus cuniculus). The rabbit exhibited granulomatous pneumonia with tracheobronchial lymph node enlargement. Histopathologically, the lung was expanded by myriad, densely cellular, heterophilic and granulomatous foci, surrounding bi- to trilaminar adiaspores. Adiaspore density was considered to be similar in all lung lobes. In the left caudal lung lobe, 80 adiaspores were counted in a 50-mm2 area using digital image analysis. The mean and median adiaspore diameters were 240 ± 52 µm and 255 µm, respectively. Tracheobronchial lymph nodes exhibited moderate numbers of similar adiaspores. PCR amplification of DNA extracted from microdissected adiaspores failed to identify Emmonsia spp.-specific DNA. These data suggest that adiaspiromycosis may result in severe granulomatous pneumonia in wild European rabbits. Although confirmation of the etiologic agent by PCR using DNA extracted from formalin-fixed tissue is not always successful, digital image analysis can be used to aid accurate assessment of adiaspore density and morphology.
Subject(s)
Chrysosporium/isolation & purification , Lung Diseases, Fungal/veterinary , Mycoses/veterinary , Rabbits , Animals , Chrysosporium/genetics , Lung Diseases, Fungal/microbiology , Lung Diseases, Fungal/pathology , Mycoses/diagnosis , Mycoses/microbiologyABSTRACT
We report 4 patients in North America with disease caused by Emergomyces canadensis, a newly proposed species of pathogenic dimorphic fungus. Affected persons were immunocompromised; lived in Saskatchewan, Colorado, and New Mexico; and had systemic disease involving blood, skin, cervix, lung, and lymph node. Two cases were fatal.
Subject(s)
Ascomycota , Mycoses/epidemiology , Mycoses/microbiology , Adult , Aged , Antifungal Agents/pharmacology , Ascomycota/classification , Ascomycota/drug effects , Ascomycota/genetics , Ascomycota/isolation & purification , Comorbidity , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , North America/epidemiologyABSTRACT
We detected Emergomyces africanus, a thermally dimorphic fungus that causes an HIV-associated systemic mycosis, by PCR in 18 (30%) of 60 soil samples from a wide range of habitats in South Africa. Direct and indirect culture techniques were unsuccessful. Experimental intraperitoneal inoculation of conidia induced murine disease.
Subject(s)
Ascomycota/isolation & purification , Mycoses/microbiology , Soil Microbiology , Animals , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , South AfricaABSTRACT
BACKGROUND: The northern hairy-nosed wombat (Lasiorhinus krefftii) is critically endangered, with only 200 individuals remaining in the wild. Individuals are rarely available for detailed pathological assessment and identification of disease threats to individuals is critically important to species conservation. CASE REPORT: Two male northern hairy-nosed wombats, part of the Richard Underwood Nature Refuge population, were presented for necropsy, 5 months apart. They were found to have succumbed to adiaspiromycosis caused by the fungus Emmonsia parva. Pathological presentations were of severe pulmonary oedema and fibrosis, and pleuritis, respectively. Characteristic fungal adiaspores were noted on histopathological examination. The wombats had concurrent variably severe ectoparasite and endoparasite burdens. CONCLUSION: These are the first reported cases of adiaspiromycosis in northern hairy-nosed wombats and the organism was associated with significant pathological changes. The rarity and the logistical challenges of presenting northern hairy-nosed wombats for pathological assessment are a challenge to identifying disease threats in this critically endangered species.
Subject(s)
Chrysosporium/isolation & purification , Lung Diseases, Fungal/veterinary , Marsupialia , Animals , Animals, Zoo , Autopsy , Intestines/parasitology , Lung Diseases, Fungal/diagnosis , Lung Diseases, Fungal/pathology , Male , Mycoses/diagnosis , Mycoses/veterinaryABSTRACT
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
A novel dimorphic fungus, Emergomyces orientalis sp. nov. a close relative of systemic pathogens in the family Ajellomycetaceae (Blastomyces, Histoplasma). The fungus is reported in a 64-year-old male from Shanxi, China. The patient developed disseminated skin lesions, productive cough with fever and showed nodular opacities in his left lung on chest radiography. The patient had no identified cause of immunodeficiency apart from type-2 diabetes mellitus. Clinical, histopathological and mycological characteristics of the agent are given, and its phylogenetic position is determined with multilocus sequence data.
Subject(s)
Invasive Fungal Infections/diagnosis , Invasive Fungal Infections/microbiology , Onygenales/isolation & purification , Onygenales/pathogenicity , Phylogeny , Blastomyces/genetics , China , DNA, Ribosomal , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/microbiology , Fever/etiology , Fever/microbiology , Histoplasma/genetics , Humans , Lung/diagnostic imaging , Lung/microbiology , Lung/pathology , Male , Middle Aged , Multilocus Sequence Typing , Onygenales/classification , Onygenales/genetics , Sequence Analysis, DNA , Skin/microbiology , Skin/pathology , Tomography, X-Ray ComputedABSTRACT
Recent discoveries of novel systemic fungal pathogens with thermally dimorphic yeast-like phases have challenged the current taxonomy of the Ajellomycetaceae, a family currently comprising the genera Blastomyces, Emmonsia, Emmonsiellopsis, Helicocarpus, Histoplasma, Lacazia and Paracoccidioides. Our morphological, phylogenetic and phylogenomic analyses demonstrated species relationships and their specific phenotypes, clarified generic boundaries and provided the first annotated genome assemblies to support the description of two new species. A new genus, Emergomyces, accommodates Emmonsia pasteuriana as type species, and the new species Emergomyces africanus, the aetiological agent of case series of disseminated infections in South Africa. Both species produce small yeast cells that bud at a narrow base at 37°C and lack adiaspores, classically associated with the genus Emmonsia. Another novel dimorphic pathogen, producing broad-based budding cells at 37°C and occurring outside North America, proved to belong to the genus Blastomyces, and is described as Blastomyces percursus.
Subject(s)
Mycoses/microbiology , Onygenales/classification , Onygenales/genetics , Blastomyces/genetics , Chrysosporium/genetics , Genome, Fungal , Histoplasma/genetics , Humans , Microscopy , Mycelium/ultrastructure , Mycoses/epidemiology , North America/epidemiology , Onygenales/pathogenicity , Onygenales/ultrastructure , Phenotype , Phylogeny , Sequence Analysis, DNA , South Africa/epidemiology , Spores, Fungal/ultrastructureABSTRACT
We report a fatal case of disseminated Emmonsia sp. infection in a 55-year-old man who received an orthotopic liver transplant. The patient had pneumonia and fungemia, and multisystem organ failure developed. As human habitats and the number of immunocompromised patients increase, physicians must be aware of this emerging fungal infection.
Subject(s)
Fungemia/diagnosis , Fungemia/microbiology , Liver Transplantation/adverse effects , Mycoses/diagnosis , Mycoses/microbiology , Antifungal Agents/therapeutic use , Fatal Outcome , Fungemia/drug therapy , Humans , Immunocompromised Host , Male , Middle Aged , Mycoses/drug therapy , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: Stoat (Mustela erminea) and weasel (Mustela nivalis) populations in south-west England are declining whilst polecats (Mustela putorius), absent for over a century, are increasing. Little is known about the health status of these species nationally. This study aimed at investigating respiratory disease in specimens found dead in south-west England. RESULTS: Trauma caused by road traffic, predator attack or being trapped was the predominant cause of death in 42 stoats, 31 weasels and 20 polecats; most were in good physical condition. Skrjabingylus nasicola was present in all species (weasels 37%, polecats 39%, stoats 41%) and infected animals showed no evidence of loss of body condition. Even in carcases stored frozen L1 larvae were frequently alive and highly motile. Angiostrongylus vasorum infection was diagnosed in two stoats and one weasel: in stoats infections were patent and the lung lesions were likely of clinical significance. These are believed to be the first records of A. vasorum in small mustelids. Pleuritis and pyothorax was seen in two polecats, in one case due to a migrating grass awn. Histological examination of lungs showed granulomata in stoats (38%), weasels (52%) and polecats (50%). Spherules consistent with Emmonsia spp. adiaspores were present in the granulomata of stoats (60%), weasels (36%) and polecats (29%). Adiaspore diameter in all three species was similar (means: stoats 39 µm, weasels 30 µm, polecats 36 µm); these are markedly smaller than that normally recorded for E. crescens. Although they lie within the accepted range for spores of Emmonsia parva this arid-zone species is not found in Britain, thus raising a question over the identity of the fungus. Cases showing numerous granulomata but few or no adiaspores were Ziehl-Neelsen-stain negative for acid-fast bacilli and IHC negative for Mycobacterium spp. However, in some cases PCR analyses revealed mycobacteria, including Mycobacterium kumamotonense and Mycobacterium avium Complex. One stoat had numerous unidentified small organisms present centrally within granulomata. CONCLUSIONS: Stoats, weasels and polecats in south-west England share several respiratory diseases, often of high prevalence, but the pathology would appear insufficient to impact on the health status of the populations and other ultimate causes of death should be investigated when examining these species.
Subject(s)
Mustelidae , Respiratory Tract Diseases/veterinary , Animals , Cause of Death , England , Female , Male , Mustelidae/microbiology , Mustelidae/parasitology , Respiratory Tract Diseases/mortalityABSTRACT
We report here the first case of disseminated Emmonsia pasteuriana infection in a patient with AIDS in India. The patient presented with weight loss, dyspnoea, left-sided chest pain and multiple non-tender skin lesions over face and body for 3 months. Disseminated emmonsiosis was diagnosed on microscopic examination and fungal culture of skin biopsy and needle aspirate of lung consolidation. It was confirmed by sequencing internal transcribed spacer region of rDNA, beta tubulin, actin, and intein PRP8. The patient responded to amphotericin B and itraconazole therapy.
Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , Chrysosporium/isolation & purification , Mycoses/diagnosis , AIDS-Related Opportunistic Infections/drug therapy , AIDS-Related Opportunistic Infections/microbiology , Adult , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Biopsy, Needle , Chest Pain/microbiology , Chrysosporium/classification , Chrysosporium/genetics , DNA, Fungal/isolation & purification , DNA, Ribosomal/isolation & purification , Diagnostic Errors , Dyspnea/microbiology , Female , Humans , India/epidemiology , Itraconazole/therapeutic use , Mycoses/drug therapy , Mycoses/microbiology , Phylogeny , Weight LossABSTRACT
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.