Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 849
Filtrar
Mais filtros

Coleção BVS Equador
Intervalo de ano de publicação
1.
PLoS Pathog ; 18(6): e1010417, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35731824

RESUMO

Intracellular pathogens secrete effectors to manipulate their host cells. Histoplasma capsulatum (Hc) is a fungal intracellular pathogen of humans that grows in a yeast form in the host. Hc yeasts are phagocytosed by macrophages, where fungal intracellular replication precedes macrophage lysis. The most abundant virulence factor secreted by Hc yeast cells is Calcium Binding Protein 1 (Cbp1), which is absolutely required for macrophage lysis. Here we take an evolutionary, structural, and cell biological approach to understand Cbp1 function. We find that Cbp1 is present only in the genomes of closely related dimorphic fungal species of the Ajellomycetaceae family that lead primarily intracellular lifestyles in their mammalian hosts (Histoplasma, Paracoccidioides, and Emergomyces), but not conserved in the extracellular fungal pathogen Blastomyces dermatitidis. We observe a high rate of fixation of non-synonymous substitutions in the Cbp1 coding sequences, indicating that Cbp1 is under positive selection. We determine the de novo structures of Hc H88 Cbp1 and the Paracoccidioides americana (Pb03) Cbp1, revealing a novel "binocular" fold consisting of a helical dimer arrangement wherein two helices from each monomer contribute to a four-helix bundle. In contrast to Pb03 Cbp1, we show that Emergomyces Cbp1 orthologs are unable to stimulate macrophage lysis when expressed in the Hc cbp1 mutant. Consistent with this result, we find that wild-type Emergomyces africanus yeast are able to grow within primary macrophages but are incapable of lysing them. Finally, we use subcellular fractionation of infected macrophages and indirect immunofluorescence to show that Cbp1 localizes to the macrophage cytosol during Hc infection, making this the first instance of a phagosomal human fungal pathogen directing an effector into the cytosol of the host cell. We additionally show that Cbp1 forms a complex with Yps-3, another known Hc virulence factor that accesses the cytosol. Taken together, these data imply that Cbp1 is a fungal virulence factor under positive selection that localizes to the cytosol to trigger host cell lysis.


Assuntos
Proteínas de Ligação ao Cálcio , Histoplasmose , Macrófagos , Fatores de Virulência , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Histoplasma/metabolismo , Histoplasmose/microbiologia , Humanos , Macrófagos/microbiologia , Mamíferos , Saccharomyces cerevisiae , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
2.
MMWR Morb Mortal Wkly Rep ; 73(11): 239-244, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512795

RESUMO

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.


Assuntos
Blastomicose , COVID-19 , Coccidioidomicose , Histoplasmose , Infecções Respiratórias , Humanos , Estados Unidos/epidemiologia , Blastomicose/epidemiologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Coccidioidomicose/diagnóstico , Coccidioidomicose/epidemiologia , Pandemias , COVID-19/epidemiologia , Infecções Respiratórias/epidemiologia
3.
Med Mycol ; 62(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39104225

RESUMO

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.


Assuntos
DNA Fúngico , Histoplasma , Histoplasmose , Doenças dos Cavalos , Tipagem de Sequências Multilocus , Filogenia , Animais , Histoplasma/genética , Histoplasma/classificação , Histoplasma/isolamento & purificação , Etiópia , Histoplasmose/microbiologia , Histoplasmose/veterinária , Cavalos/microbiologia , Doenças dos Cavalos/microbiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Análise de Sequência de DNA , Técnicas de Tipagem Micológica
4.
Med Mycol ; 62(6)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935903

RESUMO

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.


Assuntos
Antifúngicos , Farmacorresistência Fúngica , Histoplasma , Histoplasmose , Organização Mundial da Saúde , Humanos , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Histoplasmose/tratamento farmacológico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Histoplasma/efeitos dos fármacos , Histoplasma/isolamento & purificação , Prevalência , Hospedeiro Imunocomprometido
5.
Epidemiol Infect ; 152: e83, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705586

RESUMO

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.


Assuntos
Quirópteros , Histoplasma , Histoplasmose , Animais , Quirópteros/microbiologia , Brasil/epidemiologia , Histoplasma/genética , Histoplasma/isolamento & purificação , Histoplasmose/epidemiologia , Histoplasmose/veterinária , Histoplasmose/microbiologia , Reação em Cadeia da Polimerase/veterinária
6.
Transpl Infect Dis ; 26(3): e14269, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38501790

RESUMO

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.


Assuntos
Histoplasma , Histoplasmose , Transplante de Rim , Tenossinovite , Humanos , Transplante de Rim/efeitos adversos , Histoplasmose/diagnóstico , Histoplasmose/tratamento farmacológico , Histoplasmose/microbiologia , Histoplasma/isolamento & purificação , Feminino , Idoso , Tenossinovite/microbiologia , Tenossinovite/tratamento farmacológico , Antifúngicos/uso terapêutico , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Transplantados
7.
An Acad Bras Cienc ; 96(suppl 1): e20231287, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258695

RESUMO

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.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Histoplasma , Histoplasmose , Reação em Cadeia da Polimerase , Humanos , Histoplasmose/diagnóstico , Histoplasmose/microbiologia , Histoplasma/genética , Histoplasma/isolamento & purificação , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Masculino , Feminino , DNA Fúngico/análise , DNA Fúngico/genética , DNA Fúngico/sangue , Adulto , Polimorfismo de Fragmento de Restrição , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/microbiologia , Pessoa de Meia-Idade
8.
Med Mycol ; 61(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38059847

RESUMO

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.


Assuntos
Histoplasmose , Doenças dos Cavalos , Linfangite , Doenças dos Ovinos , Ovinos , Animais , Cavalos , Histoplasma , Ágar , Histoplasmose/veterinária , Histoplasmose/microbiologia , Meios de Cultura , Linfangite/microbiologia , Linfangite/veterinária , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/microbiologia
9.
Med Mycol ; 61(8)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37553137

RESUMO

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.


Assuntos
Quirópteros , Histoplasmose , Humanos , Animais , Histoplasma/fisiologia , Quirópteros/microbiologia , Histoplasmose/epidemiologia , Histoplasmose/veterinária , Histoplasmose/microbiologia , Saccharomyces cerevisiae , Meio Ambiente
10.
Med Mycol ; 61(6)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37286805

RESUMO

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.


Assuntos
COVID-19 , Histoplasmose , Animais , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Histoplasmose/veterinária , Histoplasmina , Histoplasma , Estado Terminal , Anticorpos Antifúngicos , COVID-19/veterinária , Antígenos de Fungos
11.
Appl Environ Microbiol ; 88(7): e0201021, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35262368

RESUMO

Histoplasmosis is a mycotic infection principally affecting pulmonary tissue; sometimes, histoplasmosis can progress into a systemic disease. This infection involves immunocompetent and immunosuppressed human and other mammalian hosts, depending on particular circumstances. Histoplasmosis infection has been documented worldwide. The infection is acquired by inhaling infective mycelial propagules of the dimorphic fungus Histoplasma capsulatum. New reports of clinical cases of histoplasmosis in extreme latitudes could be related to human social adaptations and climate changes in the world, which are creating new favorable environments for this fungus and for bats, its major natural reservoirs and dispersers. Histoplasma has been isolated from most continents, and it is considered a complex of cryptic species, consisting of various groups of isolates that differ genetically and correlate with a particular geographic distribution. Based on updated studies, Histoplasma taxonomy is adjusting to new genetic data. Here, we have suggested that Histoplasma has at least 14 phylogenetic species distributed worldwide and new genotypes that could be under deliberation. Histoplasma's geographic radiation began in South America millions of years ago when the continents were joined and the climate was favorable. For fungal spreading, the role of bats and some birds is crucial, although other natural factors could also participate.


Assuntos
Quirópteros , Histoplasmose , Animais , Quirópteros/microbiologia , Histoplasma/genética , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Histoplasmose/veterinária , Humanos , Pulmão/microbiologia , Filogenia
12.
Epidemiology ; 33(5): 654-659, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35545229

RESUMO

BACKGROUND: In the United States, the true geographic distribution of the environmental fungus Histoplasma capsulatum remains poorly understood but appears to have changed since it was first characterized. Histoplasmosis is caused by inhalation of the fungus and can range in severity from asymptomatic to life threatening. Due to limited public health surveillance and under detection of infections, it is challenging to directly use reported case data to characterize spatial risk. METHODS: Using monthly and yearly county-level public health surveillance data and various environmental and socioeconomic characteristics, we use a spatio-temporal occupancy model to estimate latent, or unobserved, presence of H. capsulatum , accounting for imperfect detection of histoplasmosis cases. RESULTS: We estimate areas with higher probabilities of the presence of H. capsulatum in the East North Central states around the Great Lakes, reflecting a shift of the endemic region to the north from previous estimates. The presence of H. capsulatum was strongly associated with higher soil nitrogen levels. CONCLUSIONS: In this investigation, we were able to mitigate challenges related to reporting and illustrate a shift in the endemic region from historical estimates. This work aims to help inform future surveillance needs, clinical awareness, and testing decisions for histoplasmosis.


Assuntos
Histoplasma , Histoplasmose , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Humanos , Vigilância em Saúde Pública , Estados Unidos/epidemiologia
13.
Immunity ; 39(4): 697-710, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-24138881

RESUMO

Macrophages possess numerous mechanisms to combat microbial invasion, including sequestration of essential nutrients, like zinc (Zn). The pleiotropic cytokine granulocyte macrophage-colony stimulating factor (GM-CSF) enhances antimicrobial defenses against intracellular pathogens such as Histoplasma capsulatum, but its mode of action remains elusive. We have found that GM-CSF-activated infected macrophages sequestered labile Zn by inducing binding to metallothioneins (MTs) in a STAT3 and STAT5 transcription-factor-dependent manner. GM-CSF upregulated expression of Zn exporters, Slc30a4 and Slc30a7; the metal was shuttled away from phagosomes and into the Golgi apparatus. This distinctive Zn sequestration strategy elevated phagosomal H⁺ channel function and triggered reactive oxygen species generation by NADPH oxidase. Consequently, H. capsulatum was selectively deprived of Zn, thereby halting replication and fostering fungal clearance. GM-CSF mediated Zn sequestration via MTs in vitro and in vivo in mice and in human macrophages. These findings illuminate a GM-CSF-induced Zn-sequestration network that drives phagocyte antimicrobial effector function.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Histoplasma/imunologia , Histoplasmose/metabolismo , Macrófagos Peritoneais/imunologia , Superóxidos/metabolismo , Zinco/metabolismo , Animais , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/imunologia , Regulação da Expressão Gênica , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/imunologia , Complexo de Golgi/microbiologia , Histoplasma/efeitos dos fármacos , Histoplasmose/imunologia , Histoplasmose/microbiologia , Interações Hospedeiro-Patógeno , Humanos , Ativação de Macrófagos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/microbiologia , Metalotioneína/genética , Metalotioneína/imunologia , Camundongos , Camundongos Transgênicos , NADPH Oxidases/genética , NADPH Oxidases/imunologia , Fagossomos/efeitos dos fármacos , Fagossomos/imunologia , Fagossomos/microbiologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Transdução de Sinais , Superóxidos/imunologia , Zinco/imunologia
14.
Retina ; 42(2): 369-374, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34690340

RESUMO

PURPOSE: To investigate the relationship of smoking, urbanicity, and diabetes to presumed ocular histoplasmosis syndrome (POHS) and associated choroidal neovascularization (CNV). METHODS: Medical records of 751 adult patients with POHS were reviewed, including 603 patients without CNV and 148 patients with CNV. Age-matched and gender-matched controls were randomly selected from the same practice for comparison. Statistical comparisons of smoking history, urbanicity, and diabetic history were performed using chi-square and conditional logistic regression analyses. RESULTS: Increased rates of current or former smoking, rural residence, and diabetes were found in patients with POHS compared with controls. POHS patients with CNV had increased rates of current or former smoking and rural residence as compared with controls. CONCLUSION: A history of current or past smoking is associated with an increased risk of developing both POHS alone and POHS with CNV. We did not find a significant additional risk of smoking on the development of CNV in patients with POHS. Patients living in rural locations are more likely than those in urban locations to develop both POHS and POHS with CNV. Diabetics may be more likely to develop POHS than nondiabetics.


Assuntos
Doenças da Coroide/epidemiologia , Diabetes Mellitus/epidemiologia , Infecções Oculares Fúngicas/epidemiologia , Histoplasmose/epidemiologia , Doenças Retinianas/epidemiologia , População Rural/estatística & dados numéricos , Fumar/epidemiologia , Estudos de Casos e Controles , Doenças da Coroide/microbiologia , Neovascularização de Coroide/epidemiologia , Infecções Oculares Fúngicas/microbiologia , Feminino , Angiofluoresceinografia , Histoplasmose/microbiologia , Humanos , Indiana/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/microbiologia , Estudos Retrospectivos , Fatores de Risco , Acuidade Visual
15.
Semin Cell Dev Biol ; 89: 91-98, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29551572

RESUMO

The dimorphic fungal pathogen Histoplasma capsulatum takes advantage of the innate immune system, utilizing host macrophages as a proliferative niche while largely avoiding stimulation of signaling host receptors. As a result, innate immune cells are unable to control H. capsulatum on their own. Not all host phagocytes respond to H. capsulatum in the same way, with neutrophils and dendritic cells playing important roles in impeding fungal growth and initiating a protective TH1 response, respectively. Dendritic cells prime T-cell differentiation after internalization of yeasts via VLA-5 receptors and subsequent degradation of the yeasts. Dendritic cell-expressed TLR7 and TLR9 promote a type I interferon response for TH1 polarization. In contrast to dendritic cells, macrophages provide a hospitable intracellular environment. H. capsulatum yeasts enter macrophages via binding to phagocytic receptors. Simultaneously, α-glucan masks immunostimulatory cell wall ß-glucans and a secreted endoglucanase removes exposed ß-glucans to minimize recognition of yeasts by Dectin-1. This review highlights how phagocytes interact with H. capsulatum yeasts and the mechanisms H. capsulatum uses to limit the innate immune response.


Assuntos
Histoplasma/imunologia , Histoplasmose/imunologia , Imunidade Inata , Ativação Linfocitária/imunologia , Animais , Diferenciação Celular/imunologia , Parede Celular/imunologia , Parede Celular/microbiologia , Células Dendríticas/imunologia , Células Dendríticas/microbiologia , Histoplasma/patogenicidade , Histoplasmose/microbiologia , Humanos , Macrófagos/imunologia , Macrófagos/microbiologia , Neutrófilos/imunologia , Neutrófilos/microbiologia , Linfócitos T/imunologia , Linfócitos T/microbiologia
16.
J Clin Immunol ; 41(3): 545-551, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33387157

RESUMO

We present a case of central nervous system (CNS) histoplasmosis in a previously healthy adult with hepatitis C (HCV) presenting with neurological symptoms refractory to antifungal therapy and ventriculoperitoneal (VP) shunting 4 months after initial diagnosis. Persistent symptoms were thought to be inflammatory rather than infectious given negative cerebrospinal fluid (CSF) and serum fungal antigens. The patient promptly improved after initiation of corticosteroid therapy. Elevated CSF cytokines and regional enhancement on brain MRI resolved with corticosteroid treatment. This is the first case of Histoplasma-associated post-infectious inflammatory response syndrome (Histo-PIIRS) documented by CSF cytokine reduction in response to corticosteroid therapy.


Assuntos
Infecções Fúngicas do Sistema Nervoso Central/complicações , Histoplasmose/complicações , Doenças Neuroinflamatórias/diagnóstico , Doenças Neuroinflamatórias/etiologia , Biomarcadores , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Citocinas/metabolismo , Histoplasmose/microbiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Doenças Neuroinflamatórias/terapia , Avaliação de Sintomas , Síndrome , Adulto Jovem
17.
Curr Top Microbiol Immunol ; 422: 157-191, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30043340

RESUMO

Histoplasmosis, caused by the dimorphic environmental fungus Histoplasma capsulatum, is a major mycosis on the global stage. Acquisition of the fungus by mammalian hosts can be clinically silent or it can lead to life-threatening systemic disease, which can occur in immunologically intact or deficient hosts, albeit severe disease is more likely in the setting of compromised cellular immunity. H. capsulatum yeast cells are highly adapted to the mammalian host as they can effectively survive within intracellular niches in select phagocytic cells. Understanding the biological response by both the host and H. capsulatum will facilitate improved approaches to prevent and/or modify disease. This review presents our current understanding of the major pathogenic mechanisms involved in histoplasmosis.


Assuntos
Histoplasma/patogenicidade , Histoplasmose/microbiologia , Animais , Histoplasma/imunologia , Histoplasmose/imunologia , Humanos , Virulência
18.
BMC Gastroenterol ; 20(1): 141, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384881

RESUMO

BACKGROUND: Histoplasma capsulatum is the most common endemic mycosis in the United States and frequently presents as an opportunistic infection in immunocompromised hosts. Though liver involvement is common in disseminated histoplasmosis, primary gastrointestinal histoplasmosis of the liver in absence of lung involvement is rare. Similarly, cholestatic granulomatous hepatitis in liver histoplasmosis is rarely seen. CASE PRESENTATION: We present a rare case of primary gastrointestinal histoplasmosis manifesting with acute granulomatous hepatitis and cholestasis in a 48-year-old female with psoriatic arthritis, receiving methotrexate and infliximab. The epidemiology, risk factors, clinical presentation, diagnosis, and treatment of histoplasmosis is discussed. Furthermore, we review the published cases of biopsy-proven disseminated histoplasmosis with cholestatic jaundice to highlight histoplasmosis involvement in the liver. CONCLUSION: Histoplasmosis should be considered in immunosuppressed patients with fever, chills, abdominal pain and cholestasis with progressive jaundice, particularly in subjects without evidence of biliary obstruction. Future studies are needed to accurately assess the risk of this fungal infection, specifically in patients on immunomodulatory therapy for autoimmune disease.


Assuntos
Colestase/induzido quimicamente , Histoplasma/imunologia , Histoplasmose/induzido quimicamente , Hospedeiro Imunocomprometido/efeitos dos fármacos , Infliximab/efeitos adversos , Colestase/imunologia , Colestase/microbiologia , Feminino , Histoplasmose/imunologia , Histoplasmose/microbiologia , Humanos , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Psoríase/tratamento farmacológico , Psoríase/imunologia
19.
BMC Infect Dis ; 20(1): 717, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993529

RESUMO

BACKGROUND: Fungal peritonitis (FP) is a rare complication of peritoneal dialysis. We herein describe the second case in Asia of Histoplasma capsulatum peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD). CASE PRESENTATION: An 85-year-old woman with end-stage renal disease (ESRD) who had been on CAPD for 3 years and who had a history of 3 prior episodes of peritonitis presented with intermittent abdominal pain for 2 weeks and high-grade fever for 3 days. Elevated white blood cell (WBC) count and rare small oval budding yeasts were found in her peritoneal dialysis (PD) fluid. From this fluid, a white mold colony was observed macroscopically after 7 days of incubation, and numerous large, round with rough-walled tuberculate macroconidia along with small smooth-walled microconidia were observed microscopically upon tease slide preparation, which is consistent with H. capsulatum. The peritoneal dialysis (PD) catheter was then removed, and it also grew H. capsulatum after 20 days of incubation. The patient was switched from CAPD to hemodialysis. The patient was successfully treated with intravenous amphotericin B deoxycholate (AmBD) for 2 weeks, followed by oral itraconazole for 6 months with satisfactory result. The patient remains on hemodialysis and continues to be clinically stable. CONCLUSION: H. capsulatum peritonitis is an extremely rare condition that is associated with high morbidity and mortality. Demonstration of small yeasts upon staining of PD fluid, and isolation of slow growing mold in the culture of clinical specimen should provide important clues for diagnosis of H. capsulatum peritonitis. Prompt removal of the PD catheter and empirical treatment with amphotericin B or itraconazole is recommended until the culture results are known.


Assuntos
Histoplasma/isolamento & purificação , Histoplasmose/diagnóstico , Histoplasmose/etiologia , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Peritonite/diagnóstico , Peritonite/etiologia , Administração Intravenosa , Administração Oral , Idoso de 80 Anos ou mais , Anfotericina B/administração & dosagem , Anfotericina B/uso terapêutico , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Ásia , Ácido Desoxicólico/administração & dosagem , Ácido Desoxicólico/uso terapêutico , Combinação de Medicamentos , Feminino , Histoplasmose/tratamento farmacológico , Histoplasmose/microbiologia , Humanos , Itraconazol/administração & dosagem , Itraconazol/uso terapêutico , Falência Renal Crônica/terapia , Peritonite/tratamento farmacológico , Peritonite/microbiologia , Resultado do Tratamento
20.
Mycopathologia ; 185(5): 881-892, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31845177

RESUMO

Histoplasmosis is considered the most common invasive opportunistic fungal disease in the Americas, with outbreaks and micro-epidemics reported for over 80 years. In Brazil, this disease has been described since 1946, reaching a remarkable incidence in the population, especially during the HIV-AIDS pandemic. In this study, published and unpublished outbreaks and micro-epidemics of histoplasmosis in Brazil were revisited by accessing different database sources and evaluating epidemiological and clinical features. We have found reports spanning 1946-2017, across 10 Brazilian states and with involvement of 370 humans and 2 dogs, and 13 disseminated cases and 3 deaths were reported. Rio de Janeiro had the largest number of outbreaks (n = 20/40; 50%) reported in this study. The majority of outbreaks and micro-epidemics was reported in caves (n = 21/40; 52.5%), followed by reports in abandoned/deactivated sites (n = 6/40; 15%), mines (n = 5/40; 12.5%), chicken coops (n = 4/40; 10%). Histoplasmosis is a serious health issue in Brazil considering the attractive and growing market of ecotourism throughout more than 7000 caves, and all levels of poultry farming activity are important to raise awareness about how dangerous this neglected disease can be and establish ways to decrease exposure to contaminated environmental sources through adequate preventive measures.


Assuntos
Histoplasma , Histoplasmose , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Animais , Brasil/epidemiologia , Cavernas/microbiologia , Surtos de Doenças , Cães , Histoplasma/classificação , Histoplasma/isolamento & purificação , Histoplasma/patogenicidade , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Histoplasmose/prevenção & controle , Histoplasmose/veterinária , Humanos , Incidência , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/microbiologia , Doenças Negligenciadas/prevenção & controle , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Zoonoses/epidemiologia , Zoonoses/microbiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA