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1.
Microbiol Spectr ; 12(9): e0063424, 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39078160

RÉSUMÉ

Filamentous fungi present significant health hazards to immunocompromised individuals globally; however, the prompt and precise identification of them during infection remains challenging. In this study, a TaqMan probe-based multiplex real-time PCR (M-qPCR) assay was developed to detect simultaneously the target genes of four important pathogenic filamentous fungi: ANXC4 gene of Aspergillus fumigatus, EF1-α gene of Fusarium spp., mitochondrial rnl gene of Mucorales, and hcp100 gene of Histoplasma capsulatum. In this M-qPCR assay, the limit of detection (LoD) to all four kinds of fungi was 100 copies and the correlation coefficients (R2) were above 0.99. The specificity of this assay is 100%, and the minimum detection limit is 100 copies/reaction. In conclusion, an M-qPCR detection assay was well established with high specificity and sensitivity for rapid and simultaneous detection on four important filamentous fungi in the clinic. IMPORTANCE: World Health Organization developed the first fungal priority pathogens list (WHO FPPL) in 2022. Aspergillus fumigatus, Mucorales, Fusarium spp., and Histoplasma spp. are the four types of pathogenic fungi with filamentous morphology in the critical priority group and high priority group of WHO FPPL. These four filamentous fungal infections have become more common and severe in immunocompromised patients with the increase in susceptible populations in recent decades, which resulted in a substantial burden on the public health system. However, prompt and precise identification of them during infection remains challenging. Our study established successfully a TaqMan probe-based multiplex real-time qPCR assay for four clinically important filamentous fungi, A. fumigatus, Fusarium spp., Mucorales, and Histoplasma capsulatum, with high sensitivity and specificity, which shows promising potential for prompt and precise diagnosis against fungal infection.


Sujet(s)
Aspergillus fumigatus , Champignons , Fusarium , Histoplasma , Mucorales , Réaction de polymérisation en chaine multiplex , Réaction de polymérisation en chaine en temps réel , Sensibilité et spécificité , Réaction de polymérisation en chaine multiplex/méthodes , Humains , Réaction de polymérisation en chaine en temps réel/méthodes , Histoplasma/génétique , Histoplasma/isolement et purification , Histoplasma/classification , Aspergillus fumigatus/génétique , Aspergillus fumigatus/isolement et purification , Fusarium/génétique , Fusarium/isolement et purification , Fusarium/classification , Mucorales/génétique , Mucorales/isolement et purification , Mucorales/classification , Champignons/génétique , Champignons/isolement et purification , Champignons/classification , Mycoses/diagnostic , Mycoses/microbiologie , ADN fongique/génétique , Limite de détection
2.
Indian J Med Microbiol ; 50: 100656, 2024.
Article de Anglais | MEDLINE | ID: mdl-38925278

RÉSUMÉ

During surge of COVID-19-associated mucormycosis (CAM), we identified five cases of CAM where two different species of Mucorales were isolated. All had history of diabetes mellitus and presented with clinical features suggesting rhino-orbital mucormycosis. The patients grew different species from their nasal scraping/biopsy samples, Rhizopus arrhizus, R. homothallicus (n = 2); R. homothallicus, Lictheimia corymbifera (n = 1); R. arrhizus, Mucor spp (n = 1); and L. corymbifera, Apophysomyces variabilis (n = 1). All patients underwent surgical and medical (liposomal amphotericin B) treatment. All, except one growing A. variabilis and L. corymbifera survived. Mixed infection by more than one Mucorales in CAM is unique and warrants epidemiological investigation.


Sujet(s)
COVID-19 , Mucorales , Mucormycose , Mucormycose/diagnostic , Mucormycose/microbiologie , Humains , Mucorales/isolement et purification , Mucorales/classification , Mâle , Adulte d'âge moyen , COVID-19/complications , Femelle , Antifongiques/usage thérapeutique , Amphotéricine B/usage thérapeutique , Adulte , SARS-CoV-2 , Sujet âgé
3.
Emerg Infect Dis ; 30(6): 1245-1248, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38782142

RÉSUMÉ

Choanephora infundibulifera is a member of the Mucorales order of fungi. The species is associated with plants as a saprophyte or parasite and may be responsible for spoilage or disease but is an uncommon cause of human infection. We describe C. infundibulifera rhinosinusitis in a young man with leukemia in Tennessee, USA.


Sujet(s)
Sinusite , Humains , Mâle , Tennessee , Sinusite/microbiologie , Sinusite/diagnostic , Sinusite/parasitologie , Leucémie-lymphome lymphoblastique à précurseurs B et T/complications , Mucormycose/diagnostic , Mucormycose/microbiologie , Mucormycose/traitement médicamenteux , Mucorales/isolement et purification , Mucorales/classification , Rhinite/microbiologie , Rhinite/diagnostic , Adulte , Antifongiques/usage thérapeutique ,
4.
Contrast Media Mol Imaging ; 2022: 4352730, 2022.
Article de Anglais | MEDLINE | ID: mdl-35115902

RÉSUMÉ

Currently, countries across the world are suffering from a prominent viral infection called COVID-19. Most countries are still facing several issues due to this disease, which has resulted in several fatalities. The first COVID-19 wave caused devastation across the world owing to its virulence and led to a massive loss in human lives, impacting the country's economy drastically. A dangerous disease called mucormycosis was discovered worldwide during the second COVID-19 wave, in 2021, which lasted from April to July. The mucormycosis disease is commonly known as "black fungus," which belongs to the fungus family Mucorales. It is usually a rare disease, but the level of destruction caused by the disease is vast and unpredictable. This disease mainly targets people already suffering from other diseases and consuming heavy medication to counter the disease they are suffering from. This is because of the reduction in antibodies in the affected people. Therefore, the patient's body does not have the ability to act against fungus-oriented infections. This black fungus is more commonly identified in patients with coronavirus disease in certain country. The condition frequently manifests on skin, but it can also harm organs such as eyes and brain. This study intends to design a modified neural network logic for an artificial intelligence (AI) strategy with learning principles, called a hybrid learning-based neural network classifier (HLNNC). The proposed method is based on well-known techniques such as convolutional neural network (CNN) and support vector machine (SVM). This article discusses a dataset containing several eye photographs of patients with and without black fungus infection. These images were collected from the real-time records of people afflicted with COVID followed by the black fungus. This proposed HLNNC scheme identifies the black fungus disease based on the following image processing procedures: image acquisition, preprocessing, feature extraction, and classification; these procedures were performed considering the dataset training and testing principles with proper performance analysis. The results of the procedure are provided in a graphical format with the precise specification, and the efficacy of the proposed method is established.


Sujet(s)
COVID-19/complications , Co-infection/microbiologie , Apprentissage profond , Mucorales/isolement et purification , Mucormycose/épidémiologie , Algorithmes , Comorbidité , Humains , Traitement d'image par ordinateur , Inde/épidémiologie , Mucorales/classification , Mucorales/immunologie , Mucormycose/complications , Mucormycose/microbiologie , , Machine à vecteur de support , Traitements médicamenteux de la COVID-19
5.
Nat Microbiol ; 6(3): 313-326, 2021 03.
Article de Anglais | MEDLINE | ID: mdl-33462434

RÉSUMÉ

Fungi of the order Mucorales cause mucormycosis, a lethal infection with an incompletely understood pathogenesis. We demonstrate that Mucorales fungi produce a toxin, which plays a central role in virulence. Polyclonal antibodies against this toxin inhibit its ability to damage human cells in vitro and prevent hypovolemic shock, organ necrosis and death in mice with mucormycosis. Inhibition of the toxin in Rhizopus delemar through RNA interference compromises the ability of the fungus to damage host cells and attenuates virulence in mice. This 17 kDa toxin has structural and functional features of the plant toxin ricin, including the ability to inhibit protein synthesis through its N-glycosylase activity, the existence of a motif that mediates vascular leak and a lectin sequence. Antibodies against the toxin inhibit R. delemar- or toxin-mediated vascular permeability in vitro and cross react with ricin. A monoclonal anti-ricin B chain antibody binds to the toxin and also inhibits its ability to cause vascular permeability. Therefore, we propose the name 'mucoricin' for this toxin. Not only is mucoricin important in the pathogenesis of mucormycosis but our data suggest that a ricin-like toxin is produced by organisms beyond the plant and bacterial kingdoms. Importantly, mucoricin should be a promising therapeutic target.


Sujet(s)
Mucorales/pathogénicité , Mucormycose/anatomopathologie , Mycotoxines/métabolisme , Ricine/métabolisme , Animaux , Antitoxines/immunologie , Antitoxines/pharmacologie , Antitoxines/usage thérapeutique , Apoptose , Perméabilité capillaire , Cellules cultivées , Réactions croisées , Humains , Hyphae/composition chimique , Hyphae/pathogénicité , Lectines/métabolisme , Souris , Mucorales/composition chimique , Mucorales/classification , Mucorales/génétique , Mucormycose/microbiologie , Mucormycose/prévention et contrôle , Mycotoxines/composition chimique , Mycotoxines/génétique , Mycotoxines/immunologie , Nécrose , Interférence par ARN , Rhizopus/composition chimique , Rhizopus/génétique , Rhizopus/pathogénicité , Protéines inactivant les ribosomes/métabolisme , Ricine/composition chimique , Ricine/immunologie , Virulence/effets des médicaments et des substances chimiques , Virulence/génétique
6.
J Appl Microbiol ; 131(1): 360-374, 2021 Jul.
Article de Anglais | MEDLINE | ID: mdl-33277790

RÉSUMÉ

AIMS: Root rot caused by a group of fungi is a serious disease in mulberry. This study aims to identify and characterize Rhizopus oryzae and other fungal species associated with root rot of mulberry in India. METHODS AND RESULTS: Rotted root samples were collected from the mulberry gardens from four states of Southern India. The majority of the isolates identified were R. oryzae, and others were saprophytic fungi, less abundant to occasional. Two methods of inoculations were tested to confirm the pathogenicity of the selected isolates and R. oryzae was found to be pathogenic on susceptible mulberry genotypes RC2 and SRDC-1. Multi gene phylogenetic analyses using the internal transcribed spacer region (ITS), actin (ACT) and translation elongation factor 1-α (TEF), identified the isolates as R. oryzae. Additionally, Ovatospora brasiliensis, Amesia nigricolor, Gongronella butleri, Myrmecridium schulzeri, Scedosporium boydii, Graphium euwallacea, Clonostachys rosea andTalaromyces spp. were also identified. CONCLUSION: This study revealed the existence of eleven species of fungi including the first report of R. oryzae and the occurrence of weak pathogens or saprophytes that are associated with the root rot of mulberry in India. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of R. oryzae causing Rhizopus rot of mulberry in India. Moreover, the occurrence of saprophytes associated with root rot of mulberry was identified. Further studies should focus more on the ability of these species to generate secondary metabolites and extracellular lytic enzymes as they are beneficial for the management of root rot disease.


Sujet(s)
Champignons/isolement et purification , Morus/microbiologie , Maladies des plantes/microbiologie , Rhizopus oryzae/isolement et purification , Rhizopus oryzae/pathogénicité , Ascomycota/classification , Ascomycota/isolement et purification , Champignons/classification , Champignons/génétique , Hypocreales/classification , Hypocreales/isolement et purification , Inde , Mucorales/classification , Mucorales/isolement et purification , Facteur-1 d'élongation de la chaîne peptidique/génétique , Phylogenèse , Protéines végétales/génétique , Racines de plante/microbiologie , Rhizopus oryzae/classification , Rhizopus oryzae/génétique , Scedosporium/classification , Scedosporium/isolement et purification , Sordariales/classification , Sordariales/isolement et purification , Virulence
7.
Microb Genom ; 6(12)2020 12.
Article de Anglais | MEDLINE | ID: mdl-33245689

RÉSUMÉ

Mucormycoses are invasive infections by Rhizopus species and other Mucorales. Over 10 months, four solid organ transplant (SOT) recipients at our centre developed mucormycosis due to Rhizopus microsporus (n=2), R. arrhizus (n=1) or Lichtheimia corymbifera (n=1), at a median 31.5 days (range: 13-34) post-admission. We performed whole genome sequencing (WGS) on 72 Mucorales isolates (45 R. arrhizus, 19 R. delemar, six R. microsporus, two Lichtheimia species) from these patients, from five patients with community-acquired mucormycosis, and from hospital and regional environments. Isolates were compared by core protein phylogeny and global genomic features, including genome size, guanine-cytosine percentages, shared protein families and paralogue expansions. Patient isolates fell into six core phylogenetic lineages (clades). Phylogenetic and genomic similarities of R. microsporus isolates recovered 7 months apart from two SOT recipients in adjoining hospitals suggested a potential common source exposure. However, isolates from other patients and environmental sites had unique genomes. Many isolates that were indistinguishable by core phylogeny were distinct by one or more global genomic comparisons. Certain clades were recovered throughout the study period, whereas others were found at particular time points. In conclusion, mucormycosis cases could not be genetically linked to a definitive environmental source. Comprehensive genomic analyses eliminated false associations between Mucorales isolates that would have been assigned using core phylogenetic or less extensive genomic comparisons. The genomic diversity of Mucorales mandates that multiple isolates from individual patients and environmental sites undergo WGS during epidemiological investigations. However, exhaustive surveillance of fungal populations in a hospital and surrounding community is probably infeasible.


Sujet(s)
Infections communautaires/microbiologie , Infection croisée/microbiologie , Mucorales/classification , Mucormycose/diagnostic , Transplants/microbiologie , Séquençage du génome entier/méthodes , Composition en bases nucléiques , Femelle , Variation génétique , Taille du génome , Séquençage nucléotidique à haut débit , Humains , Mâle , Mucorales/génétique , Mucorales/isolement et purification , Mucormycose/microbiologie , Phylogenèse
8.
Mycopathologia ; 185(3): 555-567, 2020 Jun.
Article de Anglais | MEDLINE | ID: mdl-32388712

RÉSUMÉ

BACKGROUND: Lichtheimia species are emerging opportunistic fungal pathogens in the Mucorales, causing serious skin and respiratory infections in immunocompromised patients. Established agents are Lichtheimia corymbifera and L. ramosa, while L. ornata is a novel agent. Available data on a species-specific analysis of Lichtheimia infections are limited. METHODS: The first case of a fatal rhino-orbital-cerebral infection in a hematopoietic stem cell transplantation recipient caused by L. ornata is reported; the agent was identified by sequencing the ITS ribosomal region. We reviewed the literature on mucormycosis due to Lichtheimia species between 2009 and 2018, with an analysis of risk factors and epidemiological and clinical data. RESULTS: In addition to our Lichtheimia ornata case, 44 cases of human Lichtheimia were analyzed. Lichtheimia predominated in Europe (68.2%), followed by Asia (16%), and Africa (9%). The most common underlying condition was hematological malignancy (36.3%), followed by trauma/major surgery (27.3%), while diabetes mellitus was rare (11.4%). Site of infection was mostly skin and soft tissues (45.5%) and lung (25%), while relatively few cases were disseminated (13.6%) or rhinocerebral (11.4%). Mortality (36.4%) was mainly due to disseminated and rhinocerebral infections. CONCLUSION: In contrast to Rhizopus, the most common agent of mucormycosis recorded in patients with diabetes mellitus, Lichtheimia infections were primarily associated with hematological malignancies and major skin barrier damage. Given the fact that classical rhinocerebral mucormycosis remains difficult to treat, independent of causative species, timely application of amphotericin B accessory to debridement may be required for patient survival.


Sujet(s)
Sujet immunodéprimé , Mucorales/pathogénicité , Mucormycose/microbiologie , Adulte , Anémie aplasique/complications , Oeil/microbiologie , Issue fatale , Femelle , Transplantation de cellules souches hématopoïétiques , Humains , Tests de sensibilité microbienne , Mucorales/classification , Mucorales/effets des médicaments et des substances chimiques , Mucorales/isolement et purification , Fosse nasale/microbiologie , Infections opportunistes/microbiologie , Phylogenèse
9.
Int J Syst Evol Microbiol ; 70(5): 3475-3482, 2020 May.
Article de Anglais | MEDLINE | ID: mdl-32379017

RÉSUMÉ

This study describes a novel fungal species belonging to the genus Gongronella. During a previous work focusing on metalaxyl degradation by Mucorales strains, two isolates from vineyard soil samples collected in the Alentejo region, south Portugal, were identified as a putative novel species based on combined molecular and MALDI-TOF MS data. This new species is described here using a polyphasic approach that combines morphology, internal transcribed spacer of ribosomal DNA (ITS) and 28S ribosomal DNA (LSU) sequence data analysis and proteomic profiling by MALDI-TOF MS. Phenotypic and molecular data enabled this novel species to be clearly distinguished from other Gongronella species with results of combined ITS+LSU analysis showing that the Gongronella species is related to Gongronella butleri and Gongronella brasiliensis. Therefore, from the results of morphological and molecular analyses, isolates MUM 10.262 and MUM 10.263 seem to represent a new Gongronella species and the name Gongronella eborensis sp. nov. is proposed, with the ex-type strain MUM 10.262 (=CCMI 1100=CBS 128763).


Sujet(s)
Mucorales/classification , Phylogenèse , Microbiologie du sol , Espaceur de l'ADN ribosomique/génétique , Mucorales/isolement et purification , Techniques de typage mycologique , Portugal , Protéomique , ARN ribosomique 28S/génétique , Analyse de séquence d'ADN , Vitis
10.
Mycologia ; 112(2): 309-328, 2020.
Article de Anglais | MEDLINE | ID: mdl-31967533

RÉSUMÉ

Species of Endogonaceae (Endogonales, Mucoromycotina) are characterized by the formation of relatively large sporocarps and zygosporangia. Numerous species in this family remain undescribed or have unclear phylogenetic positions. In Asia specifically, the species diversity of this family is almost completely unknown. However, many mycobionts of bryophytes belonging to several novel clades in Endogonaceae have recently been identified phylogenetically. Therefore, establishing a robust taxonomic system for this family is essential. We obtained numerous sporocarps of undescribed Endogonaceae-like species from the Japanese islands. Morphological observation and multilocus phylogenetic analysis of nuc 18S rDNA (18S), nuc 28S rDNA (28S), and portions of two nuclear protein-coding regions-translation elongation factor 1-alpha (tef1) and RNA polymerase II large subunit (rpb1)-from these species resulted in the description of one new species each of Endogone and Jimgerdemannia and two new species of Vinositunica, gen. nov. Because Vinositunica is characterized by purplish sporocarps and red-wine-colored chlamydospores up to 700 µm in diameter, we emended the definition of Endogonaceae.


Sujet(s)
Bryophyta/microbiologie , Mucorales , ADN fongique , Espaceur de l'ADN ribosomique , Corps fructifères de champignon/cytologie , Gènes fongiques , Japon , Mucorales/classification , Mucorales/cytologie , Mucorales/génétique , Mucorales/isolement et purification , Facteur-1 d'élongation de la chaîne peptidique/génétique , Phylogenèse , Maladies des plantes/microbiologie , ARN ribosomique 28S/génétique , Spores fongiques/cytologie
11.
Microbes Infect ; 22(8): 331-339, 2020 09.
Article de Anglais | MEDLINE | ID: mdl-31962135

RÉSUMÉ

Platelets are meanwhile recognized as versatile elements within the immune system and appear to play a key role in the innate immune response to pathogens including fungi. Previous experiments revealed platelet activation by direct contact with the hyphal-associated polysaccharide galactosaminogalactan (GAG). Since secreted fungal products may also be relevant and trigger immune reactions or thrombosis, we screened culture supernatants (SN) of human-pathogenic fungi for their capacity to activate platelets. For that purpose, platelets were incubated with SN from various fungal species; platelet activation and GAG deposition on the surface of platelets were detected by flow cytometry and electron and confocal microscopy, Culture supernatants of Aspergillus fumigatus and flavus isolates were potent platelet stimulators in a dose- and time-dependent manner, while SN of other Aspergillus species and all tested mucormycete species did not significantly induce platelet activation. The capacity of culture SN to activate platelets was dependent on fungal production of GAG and deposition of secreted GAG on the platelet surface; supernatants from mucormycetes or mutants of A. fumigatus lacking GAG secretion did not affect platelet activity. These results suggest that invading fungi can stimulate platelets not only locally through direct interactions with fungal hyphae, but can also act over a certain distance through secreted GAG.


Sujet(s)
Aspergillus/métabolisme , Polysaccharides fongiques/métabolisme , Activation plaquettaire , Polyosides/métabolisme , Aspergillus/classification , Plaquettes/métabolisme , Milieux de culture conditionnés/métabolisme , Humains , Immunité innée , Mucorales/classification , Mucorales/métabolisme , Spécificité d'espèce
12.
Med Mycol ; 58(4): 425-433, 2020 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-31342074

RÉSUMÉ

Apophysomyces elegans species complex is an important cause of cutaneous mucormycosis in India. However, majority of those cases are reported as case reports only. We desired to analyze our patients with Apophysomyces infection reported over 25 years (1992-2017) to understand the epidemiology, management, and outcome of the disease. During the study period 24 cases were reported, and the majority (95.8%) of them presented with necrotizing fasciitis following accidental/surgical/iatrogenic trauma. One patient presented with continuous ambulatory peritoneal dialysis (CAPD) related peritonitis. Healthcare related Apophysomyces infection was noted in 29.2% patients. In addition to trauma, comorbidities were noted in 37.5% patients (type 2diabetes mellitus-6, chronic alcoholism-2, and chronic kidney disease-1). Of the 24 isolates, 11 isolates starting from year 2014 were identified as Apophysomyces variabilis by molecular methods. Majority (95.8%) of the patients were managed surgically with or without amphotericin B deoxycholate therapy, while one patient was treated with amphotericin B deoxycholate alone. Among 24 patients, seven (29.1%) recovered, six (25%) patients could not afford antifungal management and left the hospital against medical advice, and 11 (45.9%) patients died.The present case series highlights that necrotizing fasciitis caused by A. variabilis is prevalent in India, and the disease may be healthcare related. Although diagnosis is not difficult, awareness among surgeons is still limited about the infection, leading to a delay in sending samples to the mycology laboratory. Apophysomyces infection must be considered in the differential diagnosis in apatient with progressive necrosis of a wound who is not responding to antibacterial therapy.


Sujet(s)
Mucorales/pathogénicité , Mucormycose/épidémiologie , Adolescent , Adulte , Sujet âgé , Antifongiques/usage thérapeutique , Comorbidité , Fasciite nécrosante/traitement médicamenteux , Fasciite nécrosante/microbiologie , Femelle , Humains , Inde/épidémiologie , Mâle , Adulte d'âge moyen , Mucorales/classification , Mucormycose/traitement médicamenteux , Mucormycose/mortalité , Études rétrospectives , Centres de soins tertiaires/statistiques et données numériques , Jeune adulte
13.
Mycopathologia ; 185(5): 765-781, 2020 Oct.
Article de Anglais | MEDLINE | ID: mdl-31734800

RÉSUMÉ

The order Mucorales is an ancient group of fungi classified in the subphylum Mucoromycotina. Mucorales are mainly fast-growing saprotrophs that belong to the first colonizers of diverse organic materials and represent a permanent part of the human environment. Several species are able to cause human infections (mucormycoses) predominantly in patients with impaired immune system, diabetes, or deep trauma. In this review, we compiled 32 reports on community- and hospital-acquired outbreaks caused by Mucorales. The most common source of mucoralean outbreaks was contaminated medical devices that are responsible for 40.7% of the outbreaks followed by contaminated air (31.3%), traumatic inoculation of soil or foreign bodies (9.4%), and the contact (6.2%) or the ingestion (6.2%) of contaminated plant material. The most prevalent species were Rhizopus arrhizus and R. microsporus causing 57% of the outbreaks. The genus Rhizomucor was dominating in outbreaks related to contaminated air while outbreaks of Lichtheimia species and Mucor circinelloides were transmitted by direct contact. Outbreaks with the involvement of several species are reported. Subtyping of strains revealed clonality in two outbreaks and no close relation in two other outbreaks. Based on the existing data, outbreaks of Mucorales can be caused by heterogeneous sources consisting of different strains or different species. Person-to-person transmission cannot be excluded because Mucorales can sporulate on wounds. For a better understanding and prevention of outbreaks, we need to increase our knowledge on the physiology, ecology, and population structure of outbreak causing species and more subtyping data.


Sujet(s)
Mucorales , Mucormycose , Infection croisée/microbiologie , Complications du diabète/microbiologie , Épidémies de maladies , Microbiologie alimentaire , Humains , Sujet immunodéprimé , Typage moléculaire/méthodes , Mucor/croissance et développement , Mucor/isolement et purification , Mucor/pathogénicité , Mucorales/classification , Mucorales/croissance et développement , Mucorales/isolement et purification , Mucorales/pathogénicité , Mucormycose/étiologie , Mucormycose/mortalité , Mucormycose/transmission , Techniques de typage mycologique/méthodes , Infections opportunistes/microbiologie , Rhizomucor/croissance et développement , Rhizomucor/isolement et purification , Rhizomucor/pathogénicité , Rhizopus/croissance et développement , Rhizopus/isolement et purification , Rhizopus/pathogénicité , Rhizopus oryzae/croissance et développement , Rhizopus oryzae/isolement et purification , Rhizopus oryzae/pathogénicité , Plaies et blessures/microbiologie
14.
Med Mycol ; 58(1): 118-123, 2020 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-30980083

RÉSUMÉ

Mucormycosis is an angio-invasive infection, predominantly acquired by inhalation of sporangiospores from the environment. However, the burden of Mucormycetes sporangiospores in the air is not well studied. We aimed to estimate the burden of Mucormycetes spores in the outdoor and indoor (hospital) environment across different seasons in north India. A total of 380 air samples from outdoor (n = 180) and indoor (n = 200) environment were included in the study. Air samples were suctioned using air sampler (100 l/min) and cultured on Dichloran Rose Bengal Chloramphenicol (DRBC) with benomyl for selective isolation of Mucormycetes. The isolates were identified by phenotypic and genotypic methods. The mean spore count (±SD) of Mucormycetes (cfu/m3) in outdoor samples varied from 0.73 (±0.96) to 8.60 (±5.70) across different seasons. In hospital, the mean spore count varied from 0.68 (±1.07) to 1.12 (±1.07) and 0.88 (±1.01) to 1.72 (±2.17) for air-conditioned wards and non-air-conditioned wards, respectively. Rhizopus arrhizus was the predominant agent isolated from both indoor and outdoor environment followed by Cunninghamella species. We also report a single isolate of the rare mucormycete agent, Apophysomyces variabilis from outdoor environment. The present study highlights the presence of low spore burden of Mucormycetes in outdoor and hospital settings in north India. This study also reports the first isolation of A. variabilis from air samples in the Indian subcontinent.


Sujet(s)
Microbiologie de l'air , Pollution de l'air intérieur , Hôpitaux , Mucorales/isolement et purification , Saisons , Spores fongiques/isolement et purification , Numération de colonies microbiennes , Génotype , Inde , Mucorales/classification , Phénotype , Spores fongiques/classification
15.
Transpl Infect Dis ; 21(5): e13163, 2019 Oct.
Article de Anglais | MEDLINE | ID: mdl-31472083

RÉSUMÉ

We report three cases of hospital-acquired mucormycosis in heart and lung transplant patients over a 6-month period. Traditional epidemiological investigation tools were used to look for a common link between patients to explain the outbreak. Genome sequencing of each fungal strain was used to supplement the investigation. By disproving a close genetic link between infecting strains of mucormycosis, we were able to conclude the outbreak investigation. Genome sequencing is a novel tool that can be used in addition to traditional epidemiologic investigations to help determine linkage of patients during outbreak investigations.


Sujet(s)
Infection croisée/microbiologie , Épidémies de maladies/statistiques et données numériques , Génome fongique , Mucorales/génétique , Mucormycose/microbiologie , Receveurs de transplantation , Sujet âgé , ADN fongique/génétique , Transplantation cardiaque/effets indésirables , Humains , Transplantation pulmonaire/effets indésirables , Mâle , Adulte d'âge moyen , Mucorales/classification , Mucormycose/diagnostic , Analyse de séquence d'ADN
16.
Environ Microbiol ; 21(12): 4563-4581, 2019 12.
Article de Anglais | MEDLINE | ID: mdl-31330072

RÉSUMÉ

Mucormycoses are life-threatening infections that affect patients suffering from immune deficiencies. We performed phagocytosis assays confronting various strains of Lichtheimia species with alveolar macrophages, which form the first line of defence of the innate immune system. To investigate 17 strains from four different continents in a comparative fashion, transmitted light and confocal fluorescence microscopy was applied in combination with automated image analysis. This interdisciplinary approach enabled the objective and quantitative processing of the big volume of image data. Applying machine-learning supported methods, a spontaneous clustering of the strains was revealed in the space of phagocytic measures. This clustering was not driven by measures of fungal morphology but rather by the geographical origin of the fungal strains. Our study illustrates the crucial contribution of machine-learning supported automated image analysis to the qualitative discovery and quantitative comparison of major factors affecting host-pathogen interactions. We found that the phagocytic vulnerability of Lichtheimia species depends on their geographical origin, where strains within each geographic region behaved similarly, but strongly differed amongst the regions. Based on this clustering, we were able to also classify clinical isolates with regard to their potential geographical origin.


Sujet(s)
Macrophages alvéolaires/immunologie , Mucorales/immunologie , Phagocytose/immunologie , Animaux , Aspergillus fumigatus/immunologie , Aspergillus fumigatus/isolement et purification , Cellules cultivées , Microbiologie de l'environnement , Interactions hôte-pathogène , Humains , Traitement d'image par ordinateur , Souris , Typage moléculaire , Mucorales/classification , Mucorales/isolement et purification , Mucormycose/immunologie , Mucormycose/microbiologie , Phylogéographie
17.
J Dairy Sci ; 102(4): 3646-3653, 2019 Apr.
Article de Anglais | MEDLINE | ID: mdl-30799113

RÉSUMÉ

Fungal spoilage remains a significant issue in dairy product quality, especially for cultured dairy products such as yogurt formulated without preservatives such as potassium sorbate. Fungal contamination can occur throughout the processing continuum, from the dairy farm environment to the finished product processing environment. As molecular characterization of fungal isolates is used more frequently, we obtained fungal isolates obtained in 2 yogurt processing facilities as part of routine fungal testing of raw materials (e.g., fruit preparations, added ingredients), in-process product samples, environmental samples (e.g., air plates, equipment surfaces such as valves, face plates, air nozzles), and finished product samples, to determine whether internal transcribed spacer (ITS) barcoding data would be helpful to support source tracking of fungal contamination issues. Internal transcribed spacer PCR amplification and sequencing allowed us to classify the 852 isolates from these 2 facilities into 200 unique ITS allelic types (AT), representing the phyla Ascomycota (743 isolates), Basidiomycota (97 isolates), and Mucoromycota (12 isolates). Thirty ITS AT were isolated from both facilities; 62 and 108 ITS AT were isolated from only facility A or only facility B, respectively. Nine ITS AT were each represented by more than 20 isolates; these AT comprised 53% of the 852 isolates. The considerable diversity of fungal isolates even within a single facility illustrates the challenge associated with controlling fungal contamination of dairy products. The ITS barcoding technique, however, did show promise for facilitating the source tracking of fungal contamination, particularly for ITS AT over-represented in a given facility. For example, we found evidence for equipment-specific reservoirs for 2 AT (14 and 219) in facility B. Our data suggest that despite its limited discriminatory power, ITS sequencing can provide initial information that can help trace fungal contamination along the processing continuum. However, development and implementation of discriminatory subtyping methods will be needed to further improve the ability to identify sources of fungal contamination in dairy facilities. Developing and implementing sampling plans that comprehensively capture yeast and mold diversity in a given processing facility remain a considerable challenge.


Sujet(s)
ADN fongique/analyse , Manipulation des aliments , Microbiologie alimentaire/méthodes , Champignons/génétique , Champignons/isolement et purification , Yaourt/microbiologie , Allèles , Animaux , Ascomycota/classification , Ascomycota/génétique , Séquence nucléotidique , Basidiomycota/classification , Basidiomycota/génétique , ADN fongique/composition chimique , ADN intergénique/composition chimique , Produits laitiers/microbiologie , Champignons/classification , Mucorales/classification , Mucorales/génétique , Acide sorbique
18.
Mycoses ; 62(4): 391-398, 2019 Apr.
Article de Anglais | MEDLINE | ID: mdl-30685896

RÉSUMÉ

BACKGROUND: Limited data exist for epidemiology and outcomes of various agents causing mucormycosis in various clinical settings from developing countries like India. OBJECTIVES: To study the epidemiology and outcomes of various agents causing mucormycosis in different clinical settings in a tertiary care hospital from South India. PATIENTS AND METHODS: We reviewed details of 184 consecutive patients with culture-proven mucormycosis with consistent clinical syndrome and supporting features from September 2005 to September 2015. RESULTS: The mean age of patients was 50.42 years; 70.97% were male. Unlike developed countries, R microsporus (29/184; 15.7%) and Apophysomyces elegans (20/184; 10.8%) also evolved as important pathogens in addition to R arrhizus in our setting. Paranasal sinuses (136/184; 73.9%) followed by musculoskeletal system (28/184; 15.2%) were the common areas of involvement. Apophysomyces elegans typically produced skin and musculoskeletal disease in immune-competent individuals with trauma (12/20; 60%) and caused significantly lower mortality (P = 0.03). R microsporus was more common in patients with haematological conditions (25% vs 15.7%) and was less frequently a cause for sinusitis than R arrhizus (27.58% vs 10.9%). The overall mortality was 30.97%. Combination therapy with surgery and antifungals offered the best chance for cure. CONCLUSIONS: Agents causing mucormycosis may have unique clinical and epidemiological characteristics.


Sujet(s)
Antifongiques/usage thérapeutique , Débridement , Mucorales/isolement et purification , Mucormycose/épidémiologie , Mucormycose/anatomopathologie , Adulte , Répartition par âge , Sujet âgé , Sujet âgé de 80 ans ou plus , Enfant , Association de médicaments/méthodes , Femelle , Tumeurs hématologiques/complications , Humains , Inde/épidémiologie , Mâle , Adulte d'âge moyen , Mucorales/classification , Mucormycose/mortalité , Mucormycose/thérapie , Répartition par sexe , Analyse de survie , Centres de soins tertiaires , Résultat thérapeutique , Infection de plaie/épidémiologie , Infection de plaie/mortalité , Infection de plaie/anatomopathologie , Infection de plaie/thérapie , Plaies et blessures/complications
19.
Med Mycol ; 57(6): 739-744, 2019 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-30428080

RÉSUMÉ

Mucormycoses are life-threatening fungal diseases that affect a variety of patients including those with diabetes mellitus or hematological malignancies. The responsible agents, the Mucorales, are opportunistic pathogens originating from the environment such as soil or decaying organic matter. The aim of the present study was to assess the prevalence and diversity of human-pathogenic species of Mucorales in commercially available foodstuffs in France. All food samples were purchased from January 2014 to May 2015 in France. A total of 159 dried food samples including spices and herbs (n = 68), herbal tea (n = 19), cereals (n = 19), vegetables (n = 14), and other foodstuffs (n = 39) were analyzed. Each strain of Mucorales was identified phenotypically, and molecular identification was performed by ITS sequencing. From the 28 (17.6%) samples that were culture-positive for Mucorales, 30 isolates were recovered. Among the isolates, 13 were identified as Rhizopus arrhizus var. arrhizus, 10 R. arrhizus var. delemar, two Rhizopus microsporus, one Lichtheimia corymbifera, three Lichtheimia ramosa, and one Syncephalastrum racemosum. Culture-positive samples originated from different countries (Europe, Asia) and brands. The samples most frequently contaminated by Mucorales were spices and herbs (19/68, 27.9%), followed by herbal tea (2/19, 10.5%), cereals (2/19, 10.5%), other food products (5/39, 12.8%). The present study showed that human-pathogenic Mucorales were frequently recovered from commercially available foodstuffs in France with a large diversity of species. The potential danger represented by Mucorales present in food for immunocompromised patients should be further analyzed.


Sujet(s)
Contamination des aliments/analyse , Microbiologie alimentaire , Variation génétique , Mucorales/classification , Mucorales/isolement et purification , Asie , Espaceur de l'ADN ribosomique/génétique , Grains comestibles/microbiologie , Europe , Paris , Plantes médicinales/microbiologie , Épices/microbiologie , Légumes/microbiologie
20.
Mycoses ; 62(2): 165-170, 2019 Feb.
Article de Anglais | MEDLINE | ID: mdl-30338581

RÉSUMÉ

BACKGROUND: Invasive mucormycosis is a rare but frequently fatal fungal disease. The acute and rapidly progressive evolution causes unfavourable outcome in 22%-59% of patients and its treatment represents a clinical challenge, especially in immunocompromised patients. Current data in paediatric oncological patients are limited. OBJECTIVES: The infection Working Group of the Italian Association of Pediatric Hematology and Oncology (AIEOP) analysed the episodes of invasive mucormycosis occurred between 2009 and 2016. PATIENTS: Fifteen cases of proven mucormycosis (male/female 8/7; median age 14.1 years, range 7.7-18.6) were reported after chemotherapy for acute leukaemia and lymphoma (12) and allogeneic stem cell transplantation (3). The aetiology was Rhizopus oryzae 4, Lichtheimia corymbifera 3 and Mucor spp. 8. RESULTS: Paranasal sinus was the primary site of infection in 14/15 patients combined with orbital involvement (9), central nervous system (8), lung (4), thyroid gland and kidney (1). All patients received liposomal Amphotericin B (L-AmB) (3-10 mg/kg), with surgical debridement in 14/15 cases. Eleven patients received maintenance treatment with posaconazole (9) or isavuconazole (2). Eight out of fifteen patients (53.3%) died, after 3-6 months. CONCLUSIONS: Mucormycosis involved mainly the sinu-orbital site and affected children >10 years. Despite aggressive treatment with high-dose L-AmB and timely surgical debridement, the mortality rate remains still high.


Sujet(s)
Tumeurs hématologiques/complications , Infections fongiques invasives/épidémiologie , Infections fongiques invasives/anatomopathologie , Mucorales/isolement et purification , Mucormycose/épidémiologie , Mucormycose/anatomopathologie , Adolescent , Antifongiques/usage thérapeutique , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Infections fongiques invasives/traitement médicamenteux , Infections fongiques invasives/microbiologie , Italie/épidémiologie , Mâle , Mucorales/classification , Mucormycose/traitement médicamenteux , Mucormycose/microbiologie , Études rétrospectives , Analyse de survie
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