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1.
An Acad Bras Cienc ; 96(suppl 1): e20231287, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39258695

RESUMEN

Histoplasmosis is caused by the fungus Histoplasma capsulatum and is often fatal for individuals with acquired immunodeficiency syndrome (AIDS). Delayed diagnosis is a major factor in worsening coinfection, as it can be mistaken for other diseases. Thus, rapid identification of Histoplasma in immunocompromised patients is essential. Molecular techniques, particularly polymerase chain reaction (PCR), were used in this study to identify H. capsulatum in patients coinfected with histoplasmosis and AIDS. Blood samples from 14 individuals with AIDS and disseminated histoplasmosis were collected and analyzed. The PCR method successfully amplified the fungal region in whole blood samples, while PCR-RFLP analysis confirmed a consistent profile in the samples. Genetic sequencing further confirmed the fungal species. Compared to clinical tests such as fungal culture and urinary antigen detection, molecular analysis proved faster, more sensitive, and cost-effective. These molecular markers can potentially be incorporated into routine diagnostics in the future. Further studies are needed to expand and enhance this diagnostic approach, particularly in patients with nonprogressive clinical forms of histoplasmosis.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA , Histoplasma , Histoplasmosis , Reacción en Cadena de la Polimerasa , Humanos , Histoplasmosis/diagnóstico , Histoplasmosis/microbiología , Histoplasma/genética , Histoplasma/aislamiento & purificación , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Masculino , Femenino , ADN de Hongos/análisis , ADN de Hongos/genética , ADN de Hongos/sangre , Adulto , Polimorfismo de Longitud del Fragmento de Restricción , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/microbiología , Persona de Mediana Edad
2.
Vet Res Commun ; 48(5): 3483-3487, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39162765

RESUMEN

This article describes the development of the pathogenic dimorphic fungus Histoplasma capsulatum var. farciminosum (HCF), which is the causative agent of Equine epizootic lymphangitis (EEL), from the mycelial form in the soil to the yeast form in the horse. In this study, the stages and morphology of HCF were identified through histopathological analysis and culture with various samples collected in Ethiopia from 15 horses showing clinical signs of EEL. In equids, especially cart horses in Ethiopia, poor-quality harnesses cause cutaneous wounds, which often attract flies facilitating the transmission of the fungus. Also, HCF infection occurs through open wounds or ocular mucous membranes when horses roll on contaminated damp soil. Respiratory histoplasmosis can occur through inhaling fungal spores, which is rare. HCF microconidia enter the lungs and skin wounds and are phagocytized by tissue-resident macrophages. The spores undergo intracellular replication within the macrophages transitioning into yeasts. The infected macrophages undergo lysis releasing pathogenic yeast cells into the surrounding tissue. Consequently, yeast-rich purulent exudate is produced, contaminating the soil in stables where yeast cells germinate into the mycelial form, and the entire process starts from the beginning.


Asunto(s)
Histoplasma , Histoplasmosis , Enfermedades de los Caballos , Caballos , Animales , Histoplasma/fisiología , Histoplasma/aislamiento & purificación , Enfermedades de los Caballos/microbiología , Enfermedades de los Caballos/patología , Histoplasmosis/veterinaria , Histoplasmosis/microbiología , Histoplasmosis/patología
3.
Med Mycol ; 62(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39104225

RESUMEN

Epizootic lymphangitis (EL) is a highly prevalent and contagious infectious disease affecting horses in many parts of Ethiopia caused by Histoplasma capsulatum sensu lato ('var. farciminosum'). In this study, 12 suspected isolates of H. capsulatum sensu lato or yeasts unidentified by conventional biochemical tests isolated from Ethiopian horses with EL were characterised by internal transcribed spacer sequencing. Six of the 12 isolates were identified to be members of H. capsulatum sensu lato and the other six were Pichia kudriavzevii (synonym: Candida krusei) (n = 3), Trichosporon asahii (n = 1), Geotrichum silvicola (n = 1) and Moesziomyces aphidis (n = 1), respectively. The six H. capsulatum sensu lato isolates were further characterised by multilocus sequence analysis. Four distinct gene loci (arf [462 bases], H-anti [410 bases], ole1 [338 bases] and tub1 [272 bases]) of these six isolates as well as those of two H. capsulatum sensu lato ('var. farciminosum') reference strains (ATCC 58332 and ATCC 28798) were polymerase chain reaction (PCR)-amplified and sequenced. Phylogenetic analyses of their concatenated nucleotide sequences showed that three of the isolates and the reference strain ATCC 58332 were identical and belonged to the Eurasia clade within Latin American (LAm) A (H. suramericanum), and those of the other three isolates and the reference strain ATCC 28798 were identical and belonged to the Africa clade. At least two distinct phylogenetic clades of H. capsulatum sensu lato were circulating in Ethiopian horses with EL. Advanced molecular technologies and bioinformatics tools are crucial for the accurate identification and typing of pathogens as well as the discovery of novel microorganisms in veterinary microbiology.


Using multilocus sequence analysis with four concatenated housekeeping gene loci, at least two distinct phylogenetic clades, namely Eurasia clade and Africa clade, of Histoplasma capsulatum sensu lato were confirmed to be circulating in Ethiopian horses with epizootic lymphangitis.


Asunto(s)
ADN de Hongos , Histoplasma , Histoplasmosis , Enfermedades de los Caballos , Tipificación de Secuencias Multilocus , Filogenia , Animales , Histoplasma/genética , Histoplasma/clasificación , Histoplasma/aislamiento & purificación , Etiopía , Histoplasmosis/microbiología , Histoplasmosis/veterinaria , Caballos/microbiología , Enfermedades de los Caballos/microbiología , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Análisis de Secuencia de ADN , Técnicas de Tipificación Micológica
4.
Med Mycol ; 62(6)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935903

RESUMEN

Histoplasmosis, a significant mycosis primarily prevalent in Africa, North and South America, with emerging reports globally, poses notable health challenges, particularly in immunocompromised individuals such as people living with HIV/AIDS and organ transplant recipients. This systematic review, aimed at informing the World Health Organization's Fungal Priority Pathogens List, critically examines literature from 2011 to 2021 using PubMed and Web of Science, focusing on the incidence, mortality, morbidity, antifungal resistance, preventability, and distribution of Histoplasma. We also found a high prevalence (22%-44%) in people living with HIV, with mortality rates ranging from 21% to 53%. Despite limited data, the prevalence of histoplasmosis seems stable, with lower estimates in Europe. Complications such as central nervous system disease, pulmonary issues, and lymphoedema due to granuloma or sclerosis are noted, though their burden remains uncertain. Antifungal susceptibility varies, particularly against fluconazole (MIC: ≥32 mg/l) and caspofungin (MICs: 4-32 mg/l), while resistance to amphotericin B (MIC: 0.125-0.16 mg/l), itraconazole (MICs: 0.004-0.125 mg/l), and voriconazole (MICs: 0.004-0.125 mg/l) remains low. This review identifies critical knowledge gaps, underlining the need for robust, globally representative surveillance systems to better understand and combat this fungal threat.


Asunto(s)
Antifúngicos , Farmacorresistencia Fúngica , Histoplasma , Histoplasmosis , Organización Mundial de la Salud , Humanos , Histoplasmosis/epidemiología , Histoplasmosis/microbiología , Histoplasmosis/tratamiento farmacológico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Histoplasma/efectos de los fármacos , Histoplasma/aislamiento & purificación , Prevalencia , Huésped Inmunocomprometido
5.
mSphere ; 9(6): e0000924, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38771035

RESUMEN

Histoplasmosis is an endemic mycosis that often presents as a respiratory infection in immunocompromised patients. Hundreds of thousands of new infections are reported annually around the world. The etiological agent of the disease, Histoplasma, is a dimorphic fungus commonly found in the soil where it grows as mycelia. Humans can become infected by Histoplasma through inhalation of its spores (conidia) or mycelial particles. The fungi transition into the yeast phase in the lungs at 37°C. Once in the lungs, yeast cells reside and proliferate inside alveolar macrophages. Genomic work has revealed that Histoplasma is composed of at least five cryptic phylogenetic species that differ genetically. Three of those lineages have received new names. Here, we evaluated multiple phenotypic characteristics (colony morphology, secreted proteolytic activity, yeast size, and growth rate) of strains from five of the phylogenetic species of Histoplasma to identify phenotypic traits that differentiate between these species: Histoplasma capsulatum sensu stricto, Histoplasma ohiense, Histoplasma mississippiense, Histoplasma suramericanum, and an African lineage. We report diagnostic traits for three species. The other two species can be identified by a combination of traits. Our results suggest that (i) there are significant phenotypic differences among the cryptic species of Histoplasma and (ii) those differences can be used to positively distinguish those species in a clinical setting and for further study of the evolution of this fungal pathogen.IMPORTANCEIdentifying species boundaries is a critical component of evolutionary biology. Genome sequencing and the use of molecular markers have advanced our understanding of the evolutionary history of fungal pathogens, including Histoplasma, and have allowed for the identification of new species. This is especially important in organisms where morphological characteristics have not been detected. In this study, we revised the taxonomic status of the four named species of the genus Histoplasma, H. capsulatum sensu stricto (ss), H. ohiense, H. mississippiense, and H. suramericanum, and propose the use of species-specific phenotypic traits to aid their identification when genome sequencing is not available. These results have implications not only for evolutionary study of Histoplasma but also for clinicians, as the Histoplasma species could determine the outcome of disease and treatment needed.


Asunto(s)
Histoplasma , Histoplasmosis , Fenotipo , Filogenia , Histoplasma/genética , Histoplasma/clasificación , Histoplasma/patogenicidad , Histoplasma/aislamiento & purificación , Histoplasmosis/microbiología , Humanos , Genoma Fúngico
6.
Microbiol Mol Biol Rev ; 88(2): e0007623, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38819148

RESUMEN

SUMMARYHistoplasmosis is arguably the most common fungal respiratory infection worldwide, with hundreds of thousands of new infections occurring annually in the United States alone. The infection can progress in the lung or disseminate to visceral organs and can be difficult to treat with antifungal drugs. Histoplasma, the causative agent of the disease, is a pathogenic fungus that causes life-threatening lung infections and is globally distributed. The fungus has the ability to germinate from conidia into either hyphal (mold) or yeast form, depending on the environmental temperature. This transition also regulates virulence. Histoplasma and histoplasmosis have been classified as being of emergent importance, and in 2022, the World Health Organization included Histoplasma as 1 of the 19 most concerning human fungal pathogens. In this review, we synthesize the current understanding of the ecological niche, evolutionary history, and virulence strategies of Histoplasma. We also describe general patterns of the symptomatology and epidemiology of histoplasmosis. We underscore areas where research is sorely needed and highlight research avenues that have been productive.


Asunto(s)
Variación Genética , Histoplasma , Histoplasmosis , Histoplasma/genética , Histoplasma/patogenicidad , Histoplasmosis/microbiología , Humanos , Virulencia/genética , Animales , Genotipo
7.
Epidemiol Infect ; 152: e83, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38705586

RESUMEN

The mycosis histoplasmosis is also considered a zoonosis that affects humans and other mammalian species worldwide. Among the wild mammals predisposed to be infected with the etiologic agent of histoplasmosis, bats are relevant because they are reservoir of Histoplasma species, and they play a fundamental role in maintaining and spreading fungal propagules in the environments since the infective mycelial phase of Histoplasma grows in their accumulated guano. In this study, we detected the fungal presence in organ samples of bats randomly captured in urban areas of Araraquara City, São Paulo, Brazil. Fungal detection was performed using a nested polymerase chain reaction to amplify a molecular marker (Hcp100) unique to H. capsulatum, which revealed the pathogen presence in organ samples from 15 out of 37 captured bats, indicating 40.5% of infection. Out of 22 Hcp100-amplicons generated, 41% corresponded to lung and trachea samples and 59% to spleen, liver, and kidney samples. Data from these last three organs suggest that bats develop disseminated infections. Considering that infected bats create environments with a high risk of infection, it is important to register the percentage of infected bats living in urban areas to avoid risks of infection to humans, domestic animals, and wildlife.


Asunto(s)
Quirópteros , Histoplasma , Histoplasmosis , Animales , Quirópteros/microbiología , Brasil/epidemiología , Histoplasma/genética , Histoplasma/aislamiento & purificación , Histoplasmosis/epidemiología , Histoplasmosis/veterinaria , Histoplasmosis/microbiología , Reacción en Cadena de la Polimerasa/veterinaria
8.
MMWR Morb Mortal Wkly Rep ; 73(11): 239-244, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38512795

RESUMEN

Coccidioidomycosis, histoplasmosis, and blastomycosis are lower respiratory tract fungal infections whose signs and symptoms can resemble those of other respiratory illnesses, including pneumonia caused by bacterial or viral etiologies; this overlap in clinical presentation might lead to missed or delayed diagnoses. The causative fungi live in the environment, often in soil or plant matter. To describe the epidemiologic characteristics of cases of coccidioidomycosis, histoplasmosis, and blastomycosis during the COVID-19 pandemic, CDC analyzed case surveillance data for 2019-2021. During this period, a total of 59,655 coccidioidomycosis cases, 3,595 histoplasmosis cases, and 719 blastomycosis cases were reported to CDC. In 2020, fewer cases of each disease occurred in spring compared with other seasons, and most cases occurred in fall; national seasonality is not typically observed, and cases were seasonally distributed more evenly in 2019 and 2021. Fewer cases coinciding with the start of the COVID-19 pandemic, along with an unusually high blastomycosis case fatality rate in 2021 (17% compared with more typical rates of 8%-10%), suggest that the pandemic might have affected patients' health care-seeking behavior, public health reporting practices, or clinical management of these diseases. Increased awareness and education are needed to encourage health care providers to consider fungal diseases and to identify pneumonia of fungal etiology. Standardized diagnostic guidance and informational resources for fungal testing could be incorporated into broader respiratory disease awareness and preparedness efforts to improve early diagnosis of coccidioidomycosis, histoplasmosis, and blastomycosis.


Asunto(s)
Blastomicosis , COVID-19 , Coccidioidomicosis , Histoplasmosis , Infecciones del Sistema Respiratorio , Humanos , Estados Unidos/epidemiología , Blastomicosis/epidemiología , Histoplasmosis/diagnóstico , Histoplasmosis/epidemiología , Histoplasmosis/microbiología , Coccidioidomicosis/diagnóstico , Coccidioidomicosis/epidemiología , Pandemias , COVID-19/epidemiología , Infecciones del Sistema Respiratorio/epidemiología
9.
Transpl Infect Dis ; 26(3): e14269, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38501790

RESUMEN

Histoplasmosis is an expected endemic mycosis in solid organ transplant recipients and occurs as a primary infection, reactivation, or, rarely, acquired from an infected allograft. Reactivation is favored by maintenance immunosuppression or anti-rejection therapy, which facilitates the appearance of disseminated forms as well as unusual presentations. We present the case of a 66-year-old woman with isolated tenosynovitis due to Histoplasma capsulatum 25 years after a kidney transplant.


Asunto(s)
Histoplasma , Histoplasmosis , Trasplante de Riñón , Tenosinovitis , Humanos , Trasplante de Riñón/efectos adversos , Histoplasmosis/diagnóstico , Histoplasmosis/tratamiento farmacológico , Histoplasmosis/microbiología , Histoplasma/aislamiento & purificación , Femenino , Anciano , Tenosinovitis/microbiología , Tenosinovitis/tratamiento farmacológico , Antifúngicos/uso terapéutico , Huésped Inmunocomprometido , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Receptores de Trasplantes
10.
Braz J Microbiol ; 55(2): 1331-1337, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38368282

RESUMEN

Histoplasmosis is commonly observed in AIDS patients as a neglected opportunistic disease that has an important relationship with environmental factors. The present study described the clinical characteristics of HIV/AIDS patients diagnosed with disseminated histoplasmosis in a tertiary healthcare facility in Manaus, Amazonas, Brazil, and evaluated the patients' homes and urban environmental samples as a source of exposure to Histoplasma capsulatum. A review of medical records from 2017 to 2019 of patients with HIV/AIDS associated with histoplasmosis was carried out, as well as the collection of environmental samples in the homes of these patients. These samples were subjected to DNA extraction and then subjected to qPCR. A total of 62 patients diagnosed with HIV/AIDS and histoplasmosis were identified, which corresponds to 4.5% (n = 62/1372) of the HIV/AIDS cases detected in the period. Of these, 68% (n = 42/62) were male, with a mean age of 36 years and low education. In 47% (n = 29/62) of the cases, the diagnosis of HIV/AIDS and histoplasmosis occurred simultaneously. Mortality was 45% (n = 28/62), and 68% (n = 42/62) of these patients did not regularly use highly active antiretroviral therapy. The main symptoms found were respiratory, gastrointestinal, and weight loss, and in 81% (n = 50/62), the place of residence was in an urban area. A total of 57 environmental samples were analyzed, and the presence of Histoplasma capsulatum was not detected in any of the analyzed samples. There was a high mortality rate in the studied group of patients with AIDS and histoplasmosis. Most patients reported residing in urban areas of Manaus, with no history of travel to other areas previously known as being high risk for histoplasmosis.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA , Infecciones por VIH , Histoplasma , Histoplasmosis , Humanos , Histoplasmosis/epidemiología , Histoplasmosis/microbiología , Brasil/epidemiología , Masculino , Adulto , Femenino , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Persona de Mediana Edad , Histoplasma/aislamiento & purificación , Histoplasma/genética , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Adulto Joven , Estudios Retrospectivos
11.
Microbiol Spectr ; 12(4): e0310023, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38411051

RESUMEN

Histoplasma capsulatum var. farciminosum (HCF) is a dimorphic fungus that causes epizootic lymphangitis in equids. Current diagnostic approaches, including culture, microscopy, and clinical presentation, lack speed, sensitivity, and specificity when diagnosing clinical cases. In this study, equine blood and pus samples on Whatman FTA cards from Senegal (n = 3), The Gambia (n = 19), Ethiopia (n = 16), and Mali (n = 13) were tested using a real-time PCR (qPCR) protocol. The assay was optimized and tested for its suitability to detect and quantify HCF in blood and pus loaded onto Whatman FTA cards at sampling. Whatman FTA cards were tested for their suitability for use with qPCR and were found to recover DNA more efficiently than from direct extraction. Using TaqMan fluorescent probes and specific primers, the assay demonstrated 100% analytical specificity when detecting multiple strains of Histoplasma and no false positives with off-target organisms. The assay's diagnostic performance was measured against an existing nested internal transcribed spacer PCR protocol using a receiver operating characteristic curve. The test was found to have a diagnostic specificity and sensitivity of 100% and 71.4%, respectively, when analyzing pus samples using a cycle threshold (Ct) cutoff determined by Youden's index (27.75). Blood sample cutoff Ct value was proposed at 34.55. Further optimization is required to improve the performance of the protocol when applied to blood samples. This study has, for the first time, demonstrated the ability to detect and quantify the DNA of Histoplasma spp. in equine blood and pus samples with a high degree of accuracy, providing a platform to further investigate the pathogenesis and epidemiology of this disease. IMPORTANCE: Histoplasmosis is a neglected yet major cause of morbidity and mortality in both equids and people in resource-scarce settings. One of the major hindrances to the control of histoplasmosis is a lack of readily available diagnostic tests. Tests are needed to support clinical decision-making and to be applied in population-based research to further understand this disease in situ. This paper reports, for the first time, the validation and application of a qPCR to detect Histoplasma directly from equine clinical samples, bypassing the need to culture this notoriously difficult organism. We report and comment on the performance of the qPCR in comparison with our previously developed nested PCR.


Asunto(s)
Histoplasmosis , Ácidos Nucleicos , Caballos/genética , Animales , Humanos , Histoplasma/genética , Histoplasmosis/diagnóstico , Histoplasmosis/veterinaria , Histoplasmosis/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , ADN de Hongos/genética , Supuración
12.
mSphere ; 9(2): e0070423, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38259064

RESUMEN

Histoplasma capsulatum is a dimorphic fungal pathogen acquired via inhalation of soil-resident spores. Upon exposure to mammalian body temperatures, these fungal elements transform into yeasts that reside primarily within phagocytes. Macrophages (MΦ) provide a permissive environment for fungal replication until T cell-dependent immunity is engaged. MΦ activated by granulocyte macrophage colony stimulating factor (GM-CSF) induces metallothioneins (MTs) that bind zinc (Zn) and deprive yeast cells of labile Zn, thereby disabling fungal growth. Prior work demonstrated that the zinc transporter, ZRT2, was important for fungal survival in vivo. Hence, we constructed a yeast cell reporter strain that expresses green fluorescent protein (GFP) under control of the ZRT2 zinc-regulated promoter. This reporter accurately responds to a medium devoid of Zn. ZRT2 expression increased in GM-CSF, but not interferon-γ, stimulated MΦ. To examine the in vivo response, we infected mice with a reporter yeast strain and assessed ZRT2 expression at 0, 3, 7, and 14 days post-infection (dpi). ZRT2 expression minimally increased at 3 dpi and peaked at 7 dpi, corresponding with the onset of adaptive immunity. We discovered that the major MΦ populations that restrict Zn from the fungus are interstitial MΦ and exudate MΦ. Neutralizing GM-CSF blunted the control of infection but unexpectedly increased ZRT2 expression. This increase was dependent on another cytokine that activates MΦ to control H. capsulatum replication, M-CSF. These findings illustrate the reporter's ability to sense Zn in vitro and in vivo and correlate ZRT2 expression with GM-CSF and M-CSF activation of MΦ.IMPORTANCEPhagocytes use an arsenal of defenses to control the replication of Histoplasma yeasts, one of which is the limitation of trace metals. On the other hand, H. capsulatum combats metal restriction by upregulating metal importers such as the Zn importer ZRT2. This transporter contributes to H. capsulatum pathogenesis upon activation of adaptive immunity. We constructed a fluorescent ZRT2 transcriptional reporter to probe H. capsulatum Zn sensing during infection and exposed the role for M-CSF activation of macrophages when GM-CSF is absent. These data highlight the ways in which fungal pathogens sense metal deprivation in vivo and reveal the potential of metal-sensing reporters. The work adds a new dimension to study how intracellular pathogens sense and respond to the changing environments of the host.


Asunto(s)
Histoplasma , Histoplasmosis , Ratones , Animales , Histoplasma/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Factor Estimulante de Colonias de Macrófagos/metabolismo , Histoplasmosis/microbiología , Zinc/metabolismo , Saccharomyces cerevisiae , Mamíferos
14.
Med Mycol ; 61(12)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38059847

RESUMEN

Epizootic equine lymphangitis (EEL) is a chronic fungal disease that affects equids. The causative agent is a dimorphic fungus called Histoplasma capsulatum var farciminosum. Histoplasmacapsulatum var farciminosum field strain 7 (D 2878/2023) isolated from the eye socket of an EEL Ethiopian horse was sub-cultured on four different solid media and incubated at 26°C and 37°C for 6 weeks. Details of growth morphology were recorded and shown in images during 6 weeks of incubation. Histoplasmacapsulatum var farciminosum grew best at 26°C on all four agars, but only on sheep blood agar at 37°C as small, white dry colonies.


Histoplasma capsulatum var farciminosum was isolated from the eye socket of an equine epizootic lymphangitis infected Ethiopian horse on Mycosel agar, which was sub-cultured on four different solid media at two different temperatures for 6 weeks to show its growth pattern.


Asunto(s)
Histoplasmosis , Enfermedades de los Caballos , Linfangitis , Enfermedades de las Ovejas , Ovinos , Animales , Caballos , Histoplasma , Agar , Histoplasmosis/veterinaria , Histoplasmosis/microbiología , Medios de Cultivo , Linfangitis/microbiología , Linfangitis/veterinaria , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Caballos/microbiología
15.
Curr Opin Microbiol ; 76: 102397, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37898052

RESUMEN

Fungal infections of the central nervous system (FI-CNS) are a problematic and important medical challenge considering that those most affected are immunocompromised. Individuals with systemic cryptococcosis (67-84%), candidiasis (3-64%), blastomycosis (40%), coccidioidomycosis (25%), histoplasmosis (5-20%), mucormycosis (12%), and aspergillosis (4-6%) are highly susceptible to develop CNS involvement, which often results in high mortality (15-100%) depending on the mycosis and the affected immunosuppressed population. Current antifungal drugs are limited, prone to resistance, present host toxicity, and show reduced brain penetration, making FI-CNS very difficult to treat. Given these limitations and the rise in FI-CNS, there is a need for innovative strategies for therapeutic development and treatments to manage FI-CNS in at-risk populations. Here, we discuss standards of care, antifungal drug candidates, and novel molecular targets in the blood-brain barrier, which is a protective structure that regulates movement of particles in and out of the brain, to prevent and combat FI-CNS.


Asunto(s)
Infecciones del Sistema Nervioso Central , Coccidioidomicosis , Criptococosis , Histoplasmosis , Micosis , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Micosis/microbiología , Histoplasmosis/microbiología , Coccidioidomicosis/tratamiento farmacológico , Coccidioidomicosis/microbiología , Criptococosis/tratamiento farmacológico , Infecciones del Sistema Nervioso Central/tratamiento farmacológico
16.
Microbiol Spectr ; 11(6): e0093923, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37882565

RESUMEN

IMPORTANCE: Histoplasmosis is considered one of the most important mycoses due to the increasing number of individuals susceptible to develop severe clinical forms, particularly those with HIV/AIDS or receiving immunosuppressive biological therapies, the high mortality rates reported when antifungal treatment is not initiated in a timely manner, and the limitations of conventional diagnostic methods. In this context, there is a clear need to improve the capacity of diagnostic tools to specifically detect the fungal pathogen, regardless of the patient's clinical condition or the presence of other co-infections. The proposed novel pathogen-specific biomarkers have the potential to be used in immunodiagnostic platforms and antifungal treatment monitoring in histoplasmosis. In addition, the bioinformatics strategy used in this study could be applied to identify potential diagnostic biomarkers in other models of fungal infection of public health importance.


Asunto(s)
Histoplasmosis , Micosis , Humanos , Histoplasmosis/diagnóstico , Histoplasmosis/tratamiento farmacológico , Histoplasmosis/microbiología , Antifúngicos/uso terapéutico , Micosis/diagnóstico , Biomarcadores , Histoplasma
17.
J Investig Med High Impact Case Rep ; 11: 23247096231205347, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37811883

RESUMEN

Histoplasma capsulatum is a dimorphic fungus found in certain parts of North, Central, and South America. Transmission is primarily through airborne inoculation from inhaled fungal microconidia. Histoplasmosis is typically a self-limited mycosis; however, in patients with immunodeficiency, disseminated disease can occur and may lead to high disease burden. This report studies a case of disseminated histoplasmosis in a patient newly diagnosed with human immunodeficiency virus. His presentation on admission was consistent with infectious pulmonary granulomatous disease, and further imaging and laboratory results showed evidence of multi-organ involvement. It is likely his presentation in Central California was a reactivation infection after inoculation in Central America many years ago.


Asunto(s)
Histoplasmosis , Humanos , Histoplasmosis/diagnóstico , Histoplasmosis/tratamiento farmacológico , Histoplasmosis/microbiología , Histoplasma , Huésped Inmunocomprometido , California
18.
Med Mycol ; 61(8)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37553137

RESUMEN

Histoplasma species infect humans and animals, notably bats. Histoplasma species are thermally dimorphic fungi existing in mycelial form in the natural environment and in yeast form in infected tissues. In this narrative literature review, we summarize the occurrence of Histoplasma spp. in different species of bat tissues (n = 49) and in soil admixed with bat guano where the species of bat dwelling nearby has been identified (an additional 18 species likely infected) to provide an up-to-date summary of data. Most positive isolations are from the Americas and Caribbean, with some studies from Thailand, Malaysia, Nigeria, Slovenia, France, and Australia. We also summarize some of the early experimental work to elucidate pathogenicity, latency, immune response, and faecal excretion in bats. Given the recent recognition of the global extent of histoplasmosis, thermal dimorphism in Histoplasma spp., and global heating, additional work on understanding the complex relationship between Histoplasma and bats is desirable.


The fungal genus Histoplasma causes lung, disseminated, gut and adrenal disease in humans, many with AIDS, but also people with normally functioning immune systems. Exposure and outbreaks are often linked to visiting caves where bats reside. In some locations, considerable quantities of Histoplasma fungus are found in bat guano and, when airborne, can cause infection. There are over 1400 species of bat worldwide. We reviewed the literature from 1962, the first recorded description of bat infection by Histoplasma, and found 49 different species of bat recorded as being infected. Most of the data are from the Americas, very little from Africa, and some from hyperendemic areas in SE Asia. Histoplasma are temperature sensitive fungi and bats, especially those which hibernate and use torpor to survive winter-time shortages of insect prey, occupy environments with a wide range of temperatures. Our understanding of bat infection or latency, in a world with extremes of weather and general heating, is likely to change the Histoplasma/bat relationship in uncertain ways.


Asunto(s)
Quirópteros , Histoplasmosis , Humanos , Animales , Histoplasma/fisiología , Quirópteros/microbiología , Histoplasmosis/epidemiología , Histoplasmosis/veterinaria , Histoplasmosis/microbiología , Saccharomyces cerevisiae , Ambiente
19.
Med Mycol ; 61(6)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37286805

RESUMEN

Patients with severe COVID-19 are at increased risk for invasive fungal infections, which are underestimated. Histoplasmosis reactivation in endemic areas should not be overlooked in this population. In a previous study, seroconversion to anti-histoplasmin antibodies by ELISA was detected in 6/39 (15.4%) patients with severe COVID-19. In this work, samples were further investigated to detect seroconversion to antibodies against the Histoplasma capsulatum 100-kDa antigen (Hcp100) by ELISA. Seroconversion to anti-Hcp100 antibodies was detected in 7/39 patients, of whom 6 also seroconverted anti-histoplasmin antibodies. These results reinforce previous findings that show histoplasmosis as an underdiagnosed fungal entity complicating COVID-19.


This study verifies that patients with severe COVID-19 at intensive care units are at risk for histoplasmosis reactivation in endemic areas. Accurate diagnosis of this deadly fungal disease among critically ill patients with COVID-19 living in endemic areas for histoplasmosis is needed.


Asunto(s)
COVID-19 , Histoplasmosis , Animales , Histoplasmosis/diagnóstico , Histoplasmosis/epidemiología , Histoplasmosis/microbiología , Histoplasmosis/veterinaria , Histoplasmina , Histoplasma , Enfermedad Crítica , Anticuerpos Antifúngicos , COVID-19/veterinaria , Antígenos Fúngicos
20.
Res Vet Sci ; 161: 80-85, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37327692

RESUMEN

Epizootic lymphangitis is a contagious, chronic and overwhelming disease of equids, characterized by chronic discharging skin nodules. This study was aimed to investigate the prevalence and associated risk factors of epizootic lymphangitis in equines at Nagele Arsi town, southeastern Ethiopia. A cross-sectional study using a random sampling technique was employed from December 2021 to June 2022 via clinical and microscopic examinations of the lesions. The overall prevalence of epizootic lymphangitis was 4.37% with a prevalence of 6.69%, 0.72%, and 0% in horses, donkeys, and mules, respectively. The sex, species, harness type, season, and body condition scores of equids have shown statistically significant differences (p < 0.05) with the prevalence of epizootic lymphangitis. Macroscopically, the lesions revealed varying degrees of nodule to ulcer on the sternum, limbs, face, and cervical region of the equine. Upon giemsa stain, fungal hyphae with a halo (unstained capsule-like) structure were observed. Histologically, pyogranulomatous inflammation with fibroplasia was appreciated. In conclusion, epizootic lymphangitis was rampant in the study area. This requires a detailed investigation incorporating a large sample size using fungal culture and other molecular techniques including PCR.


Asunto(s)
Histoplasmosis , Enfermedades de los Caballos , Linfangitis , Caballos , Animales , Linfangitis/epidemiología , Linfangitis/veterinaria , Linfangitis/complicaciones , Etiopía/epidemiología , Prevalencia , Estudios Transversales , Enfermedades de los Caballos/etiología , Equidae , Histoplasmosis/epidemiología , Histoplasmosis/microbiología , Histoplasmosis/veterinaria , Factores de Riesgo
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