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1.
Nat Commun ; 15(1): 3190, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609393

RESUMO

Coccidioidomycosis, listed as a priority mycosis by the WHO, is endemic in the United States but often overlooked in Central and South America. Employing a multi-institutional approach, we investigate how disease characteristics, pathogen genetic variation, and environmental factors impact coccidioidomycosis epidemiology and outcomes in South America. We identified 292 cases (1978-2021) and 42 outbreaks in Piauí and Maranhão states, Brazil, the largest series outside the US/Mexico epidemic zone. The male-to-female ratio was 57.4:1 and the most common activity was armadillo hunting (91.1%) 4 to 30 days before symptom onset. Most patients (92.8%) exhibited typical acute pulmonary disease, with cough (93%), fever (90%), and chest pain (77%) as predominant symptoms. The case fatality rate was 8%. Our negative binomial regression model indicates that reduced precipitation levels in the current (p = 0.015) and preceding year (p = 0.001) predict heightened incidence. Unlike other hotspots, acidic soil characterizes this region. Brazilian strains differ genomically from other C. posadasii lineages. Northeastern Brazil presents a distinctive coccidioidomycosis profile, with armadillo hunters facing elevated risks. Low annual rainfall emerges as a key factor in increasing cases. A unique C. posadasii lineage in Brazil suggests potential differences in environmental, virulence, and/or pathogenesis traits compared to other Coccidioides genotypes.


Assuntos
Coccidioidomicose , Humanos , Feminino , Masculino , Animais , Brasil/epidemiologia , Coccidioidomicose/epidemiologia , Tatus , Genômica , Genótipo
2.
Microorganisms ; 11(3)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36985136

RESUMO

Paracoccidioidomycosis (PCM) is the main and most prevalent systemic mycosis in Latin America, that until recently, it was believed to be caused only by Paracoccidioides brasiliensis (P. brasiliensis). In 2006, researchers described three cryptic species: S1, PS2, PS3, and later, another one, PS4. In 2009, Paracoccidioides lutzii (Pb01-like) was described, and in 2017, a new nomenclature was proposed for the different agents: P. brasiliensis (S1), P. americana (PS2), P. restrepiensis (PS3), and P. venezuelensis (PS4). These species are not uniformly distributed throughout Latin America and, knowing that more than one cryptic species could coexist in some regions, we aimed to identify those species in patients' biopsy samples for a better understanding of the distribution and occurrence of these recently described species in Botucatu region. The Hospital of Medical School of Botucatu-UNESP, which is a PCM study pole, is located in São Paulo State mid-west region and is classified as a PCM endemic area. Genotyping analyses of clinical specimens from these patients that have been diagnosed and treated in our Hospital could favor a possible correlation between genetic groups and mycological and clinical characteristics. For this, molecular techniques to differentiate Paracoccidioides species in these biopsies, such as DNA extraction, PCR, and sequencing of three target genes (ITS, CHS2, and ARF) were conducted. All the sequences were analyzed at BLAST to testify the presence of P. brasiliensis. The phylogenetic trees were constructed using Mega 7.0 software and showed that 100% of our positive samples were from S1 cryptic species, therefore P. brasiliensis. This is important data, demonstrating the predominance of this species in the São Paulo State region.

3.
Emerg Infect Dis ; 28(10): 2100-2104, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36148943

RESUMO

We detected Histoplasma capsulatum in soil and penguin excreta in the Antarctic Peninsula by sequencing after performing species-specific PCR, confirming previous observations that this pathogen occurs more broadly than suspected. This finding highlights the need for surveillance of emerging agents of systemic mycoses and their transmission among regions, animals, and humans in Antarctica.


Assuntos
Histoplasmose , Micoses , Animais , Regiões Antárticas , Histoplasma/genética , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/veterinária , Humanos , Solo
4.
J Fungi (Basel) ; 8(4)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35448624

RESUMO

Cryptococcus spp. are human pathogens that cause 181,000 deaths per year. In this work, we systematically investigated the virulence attributes of Cryptococcus spp. clinical isolates and correlated them with patient data to better understand cryptococcosis. We collected 66 C. neoformans and 19 C. gattii clinical isolates and analyzed multiple virulence phenotypes and host-pathogen interaction outcomes. C. neoformans isolates tended to melanize faster and more intensely and produce thinner capsules in comparison with C. gattii. We also observed correlations that match previous studies, such as that between secreted laccase and disease outcome in patients. We measured Cryptococcus colony melanization kinetics, which followed a sigmoidal curve for most isolates, and showed that faster melanization correlated positively with LC3-associated phagocytosis evasion, virulence in Galleria mellonella and worse prognosis in humans. These results suggest that the speed of melanization, more than the total amount of melanin Cryptococcus spp. produces, is crucial for virulence.

5.
Med Mycol Case Rep ; 35: 48-50, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35256962

RESUMO

We present a rare condition of mixed C. neoformans and C. gattii infection in a person living with HIV with false-negative CrAg LFA in the CSF and co-infection with paracoccidioidomycosis. Signs and symptoms are relative to respiratory tract and skin, confounding with other opportunistic disease. After negatives CrAg LFA and Indian ink staining in CSF, there was isolation of C. gattii in sputum and C. neoformans in CSF, in addition to reagent serology (double immunodiffusion) for PCM with 1/16 titer. The patient was treated with amphotericin B and TMP-SMX with good clinical response and recovery of cellular immunity after initiation of antiretroviral therapy.

6.
J Fungi (Basel) ; 7(11)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34829267

RESUMO

Cryptococcosis is a systemic fungal disease acquired from contaminated environments with propagules of the basidiomycetous yeasts of the Cryptococcus neoformans and C. gattii species complexes. The C. neoformans species complex classically comprises four major molecular types (VNI, VNII, VNIII, and VNIV), and the C. gattii species complex comprises another four (VGI, VGII, VGIII, and VGIV) and the newly identified molecular type VGV. These major molecular types differ in their epidemiological and ecological features, clinical presentations, and therapeutic outcomes. Generally, the most common isolated types are VNI, VGI, and VGII. The epidemiological profile of cryptococcosis in domestic cats is poorly studied and cats can be the sentinels for human infections. Therefore, the present study aimed to determine the molecular characterization of Cryptococcus spp. isolated from domestic cats and their dwellings in the metropolitan area of Rio de Janeiro, Brazil. A total of 36 Cryptococcus spp. strains, both clinical and environmental, from 19 cats were subtyped using multilocus sequence typing (MLST). The ploidy was identified using flow cytometry and the mating type was determined through amplification with specific pheromone primers. All strains were mating type alpha and 6/36 were diploid (all VNII). Most isolates (63.88%) were identified as VNII, a rare molecular type, leading to the consideration that this genotype is more likely related to skin lesions, since there was a high percentage (68.75%) of cats with skin lesions, which is also considered rare. Further studies regarding the molecular epidemiology of cryptococcosis in felines are still needed to clarify the reason for the large proportion of the rare molecular type VNII causing infections in cats.

7.
Microorganisms ; 10(1)2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-35056462

RESUMO

The members of the Cryptococcus neoformans and Cryptococcus gattii species complexes are the main etiological agents of cryptococcosis, a life-threatening fungal infection affecting mostly immunocompromised people, but also immunocompetent hosts or those with unrecognized risk factors [...].

8.
Braz J Microbiol ; 52(1): 279-288, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33025379

RESUMO

Cryptococcosis is a life-threatening fungal infection caused by the Cryptococcus neoformans/Cryptococcus gattii species complex. Most cases are recorded in patients suffering from HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome). However, this infection also occurs in non-HIV patients with a proportion of 10-30% of all cases. The study aimed at the clinical and molecular characterization of non-HIV patients diagnosed with cryptococcosis at the Tropical Medicine Foundation (FMT-HVD) from July 2016 to June 2019. Medical records of respective patients were analyzed to describe the course of cryptococcosis in non-HIV patients. In addition, multi-locus sequence typing (MLST) was applied to identify the sequence types of the isolated Cryptococcus strains, to perform phylogenetic analysis, and to evaluate the isolates' genetic relationship to global reference strains. Antifungal susceptibility profiles to amphotericin B, fluconazole, and itraconazole were assessed by broth microdilution. From a total of 7 patients, 4 were female, the age range varied between 10 and 53 years (median of 36.3 years). Cryptococcal meningitis was the common clinical manifestation (100%). The period between onset of symptoms and confirmed diagnosis ranged from 15 to 730 days (mean value of 172.9 days), and the observed mortality was 57.1%. Of note, comorbidities of the assessed cryptococcosis patients comprised hypertension, diabetes mellitus, and intestinal tuberculosis. Genotyping applying PCR-RFLP of the URA5 gene identified all clinical isolates as C. gattii genotype VGII. Using MLST, it was possible to discriminate the sequence types ST20 (n = 4), ST5 (n = 3), and the newly identified sequence type ST560 (n = 1). The antifungals amphotericin B, fluconazole, and itraconazole showed satisfactory inhibitory activity (microdilution test) against all C. gattii VGII strains.


Assuntos
Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Meningite Criptocócica/epidemiologia , Adolescente , Adulto , Antifúngicos/farmacologia , Brasil/epidemiologia , Criança , Cryptococcus gattii/classificação , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/patogenicidade , Cryptococcus neoformans/classificação , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/patogenicidade , Feminino , Geografia , Infecções por HIV , Humanos , Masculino , Meningite Criptocócica/microbiologia , Meningite Criptocócica/mortalidade , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Técnicas de Tipagem Micológica , Filogenia , Estudos Prospectivos , Adulto Jovem
9.
Med Mycol ; 59(3): 235-243, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32497174

RESUMO

Bloodstream infections (BSI) caused by Candida species are the fourth cause of healthcare associated infections worldwide. Non-albicans Candida species emerged in the last decades as agents of serious diseases. In this study, clinical and microbiological aspects of six patients with BSI due to the Meyerozyma (Candida) guilliermondii species complex from an oncology reference center in Brazil, were evaluated. To describe demographic and clinical characteristics, medical records of the patients were reviewed. Molecular identification of the isolates was performed by ITS1-5.8S-ITS2 region sequencing. Antifungal susceptibility was evaluated by the EUCAST method and the minimal inhibitory concentrations (MIC) assessed according to the epidemiological cutoff values. Virulence associated phenotypes of the isolates were also studied. Ten isolates from the six patients were evaluated. Five of them were identified as Meyerozyma guilliermondii and the others as Meyerozyma caribbica. One patient was infected with two M. caribbica isolates with different genetic backgrounds. High MICs were observed for fluconazole and echinocandins. Non-wild type isolates to voriconazole appeared in one patient previously treated with this azole. Additionally, two patients survived, despite infected with non-wild type strains for fluconazole and treated with this drug. All isolates produced hemolysin, which was not associated with a poor prognosis, and none produced phospholipases. Aspartic proteases, phytase, and esterase were detected in a few isolates. This study shows the reduced antifungal susceptibility and a variable production of virulence-related enzymes by Meyerozyma spp. In addition, it highlights the poor prognosis of neutropenic patients with BSI caused by this emerging species complex. LAY ABSTRACT: Our manuscript describes demographic, clinical and microbiological characteristics of patients with bloodstream infection by the Meyerozyma guilliermondii species complex at a reference center in oncology in Brazil.


Assuntos
Candidíase/sangue , Saccharomycetales/genética , Saccharomycetales/patogenicidade , Sepse/microbiologia , Adulto , Antifúngicos/farmacologia , Brasil , Candidíase/microbiologia , Estudos de Casos e Controles , Farmacorresistência Fúngica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serviço Hospitalar de Oncologia/estatística & dados numéricos , Estudos Retrospectivos , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/isolamento & purificação , Adulto Jovem
10.
J. Health Biol. Sci. (Online) ; 9(1): 1-7, 2021. tab, ilus, graf
Artigo em Português | LILACS | ID: biblio-1379577

RESUMO

Objetivos: Investigar o surto de histoplasmose em bombeiros no Distrito federal/DF, ocorrido em junho de 2017. Métodos: Realizou-se um estudo de coorte por meio das entrevistas realizadas com os bombeiros mediante um questionário semiestruturado. Considerou-se infectado o bombeiro que apresentou tomografia de tórax sugestiva de histoplasmose ou reagente nos testes de imunodifusão e/ou Western blot. Coletou-se amostra ambiental e realizou-se Nested PCR específico para Histoplasma capsulatum. Resultados: Entre 35 bombeiros, 94,3% eram homens; com a mediana de idade de 37 (24-45) anos, 28 foram classificados como infectados. A média de permanência dentro da caverna foi 25 minutos. O fator de risco associado à infecção foi o ato de entrar na caverna (RR=3,86; RA=71,6; p<0,02). Entre 14 amostras ambientais, 50% foram positivas para H. capsulatum. Conclusão: Confirmou-se o surto de histoplasmose de bombeiros em Brazlândia-DF, e foram tomadas ações como a interdição da caverna e o tratamento dos bombeiros.


Objectives: To nvestigate the outbreak of histoplasmosis in firefighters in Federal District/DF, which occurred in June 2017. Methods: A cohort study was conducted through interviews with firefighters by means of a semi-structured questionnaire. Firefighters who presented chest tomography suggestive of histoplasmosis or reacted to immunodiffusion and/or Western blot tests were considered infected. Environmental samples were collected and Nested PCR specific for Histoplasma capsulatum was performed. Results: Among 35 firefighters, 94.3% were men; with a median age of 37 (24-45) years, 28 were classified as infected. The average length of stay inside the cave was 25 minutes. The risk factor associated with infection was the act of entering the cave (RR = 3.86, RA = 71.6, p <0.02). Among 14 environmental samples, 50% were positive for H. capsulatum. Conclusion: The outbreak of histoplasmosis in firefighters in Brazlândia-DF was confirmed, and actions were taken such as banning the cave and treating the firefighters


Assuntos
Histoplasma , Histoplasmose , Surtos de Doenças , Fatores de Risco , Estudos de Coortes , Bombeiros
11.
Mem Inst Oswaldo Cruz ; 115: e200208, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696916

RESUMO

Paracoccidioides spp. isolation from environmental samples is rare and hardly reproducible. Molecular techniques have facilitated the fungal detection. However, it can be still difficult. Some strategies to enhance the capacity of DNA detection have been adopted, including the analysis of soil samples belonging to the habitat of animals from which Paracoccidioides spp. have already been isolated, notably armadillo burrows. To date, the detection of Paracoccidioides spp. has not yet been reported from outbreak hotspots. Clusters and outbreaks of acute paracoccidioidomycosis (PCM), usually a more severe clinical form, have currently occurred in urban areas being associated to climate changes, deforestation, and great constructions. These occurrences potentially signalise the fungus' environmental niche, a riddle not yet solved. The authors performed an environmental investigation in a deeply disturbed area, after a highway construction in Rio de Janeiro, Brazil, where a recent outbreak of acute PCM occurred. Specific DNA sequences of Paracoccidioides brasiliensis were detected in shallow soil samples around the highway, reinforcing the association between the road construction and this PCM outbreak.


Assuntos
Tatus , DNA Fúngico/genética , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/microbiologia , Animais , Sequência de Bases , Brasil , Ecossistema , Paracoccidioides/genética , Paracoccidioides/crescimento & desenvolvimento , Análise de Sequência de DNA , Microbiologia do Solo
12.
Microorganisms ; 8(5)2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32392852

RESUMO

Cryptococcosis, a potentially fatal mycosis in humans, is acquired via exposure to exogenous environmental sources. This study aimed to investigate the frequency, genetic diversity, and virulence of cryptococcal strains isolated from indoor dust in the Rio Negro micro-region of the Brazilian Amazon. A total of 8.9% of the studied houses were positive, recovering nine Cryptococcus neoformans VNI and 16 C. gattii VGII isolates, revealing an endemic pattern in domestic microenvironments. The International Society for Human and Animal Mycology (ISHAM) consensus multilocus sequence typing (MLST) scheme for the C. neoformans/C. gattii species complexes identified two sequence types (STs), ST93 and ST5, amongst C. neoformans isolates and six STs amongst C. gattii isolates, including the Vancouver Island Outbreak ST7 (VGIIa) and ST20 (VGIIb), the Australian ST5, and ST264, ST268 and ST445, being unique to the studied region. Virulence studies in the Galleria mellonella model showed that five C. gattii strains and one C. neoformans strain showed a similar pathogenic potential to the highly virulent Vancouver Island outbreak strain CDR265 (VGIIa). The findings of this study indicate that humans can be exposed to the agents of cryptococcosis via house dust, forming the basis for future studies to analyze the impact of early and continuous exposure to indoor dust on the development of subclinical or clinical infections.

13.
Biopreserv Biobank ; 18(3): 196-203, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32213084

RESUMO

The choice of a suitable preservation method is critical for long-term microorganisms' viability. The strains should be preserved for long periods using reliable and reproducible methods that minimize genotypic and phenotypic variations and viability losses. The methodologies are usually designed for a better performance in isolated microorganisms. However, atypical primary isolates of Cryptococcus neoformans or Cryptococcus gattii, such as mixed species or even different species of a species complex, are a challenge for long-term preservation and taxonomic review studies. The aim of this study was to evaluate which of the four preservation methods tested presented better performance in the preservation of simulated coexistence strains of C. neoformans and C. gattii. Two environmental strains, one C. gattii and one C. neoformans, were mixed in vitro to test four different preservation methods (freezing at -20°C, -80°C, -196°C, and freeze-drying). The colony-forming units from each preservation method were evaluated, and colonies were randomly selected and cultivated in canavanine glycine bromothymol blue (CGB) agar to evaluate the amounts of CGB-positive (C. gattii) and CGB-negative (C. neoformans) colonies resulting from each preservation method after 1 week, 15 days, 1 month, 6 months, and 1 year. According to our results, cryopreservation at -20°C demonstrated was preferable for C. neoformans species, and further studies after long-term storage are necessary. Recovery of yeast cells after freeze-dried preservation in skim milk is better for both species. Ultrafreezing methods evaluated (-80°C and -196°C) also showed better results in the maintenance of C. gattii. Freeze-drying should be preferred for the maintenance of multilineage isolates from the C. neoformans and C. gattii species complexes.


Assuntos
Criopreservação/métodos , Cryptococcus gattii/crescimento & desenvolvimento , Cryptococcus neoformans/crescimento & desenvolvimento , DNA Fúngico/genética , Árvores/microbiologia , Cryptococcus gattii/genética , Cryptococcus gattii/isolamento & purificação , Cryptococcus neoformans/genética , Cryptococcus neoformans/isolamento & purificação , Meios de Cultura , Liofilização , Congelamento , Instabilidade Genômica , Viabilidade Microbiana , Fenótipo , Temperatura
14.
Mycoses ; 63(2): 145-150, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31715053

RESUMO

Cryptococcal meningitis is a several disease common in late stage of HIV infection. Detection of cryptococcal antigen (CrAg) is an important for early diagnosis of this invasive mycosis. The pre-emptive treatment for isolated antigenemia prevents the onset of meningoencephalitis. Screening CrAg in patients with low CD4 count is cost-effective in countries with prevalence of antigenemia above 3%. However, in Brazil, the number of prevalence studies on cryptococcosis and HIV is insufficient. The objective of this study is to estimate the prevalence of CrAg and describe clinical characteristics from a cohort of patients followed at a reference center in Brazil. CrAg screening was performed in 89 inpatients with CD4 count ≤200 cells/mm3 or WHO stage III/IV from the National Institute of Infecttious Disease, Rio de Janeiro. Patients with isolated antigenemia received pre-emptive therapy with fluconazole and patients with meningoencephalitis were treated with Amphotericin B. Individuals were followed up for 12 months. Prevalence of serum CrAg was 11.23%, cryptococcal meningoencephalitis 6.74% and isolated antigenemia 4.81%. None of the patients with isolated antigenemia developed meningoencephalitis during the follow up. Signs and symptoms of meningoencephalitis were unspecific or absent. Our study suggests the need of CrAg screening in Brazil and highlights that lumbar puncture is mandatory in all individuals CrAg positive to exclude asymptomatic meningoencephalitis.


Assuntos
Criptococose/complicações , Infecções por HIV/complicações , Adulto , Antígenos de Fungos/sangue , Brasil/epidemiologia , Criptococose/epidemiologia , Criptococose/imunologia , Criptococose/mortalidade , Cryptococcus/imunologia , Feminino , Seguimentos , Humanos , Masculino , Meningite Criptocócica/líquido cefalorraquidiano , Meningite Criptocócica/complicações , Meningite Criptocócica/epidemiologia , Meningite Criptocócica/imunologia , Pessoa de Meia-Idade , Prevalência , Tuberculose/complicações , Tuberculose/mortalidade
15.
Mem. Inst. Oswaldo Cruz ; 115: e200208, 2020. tab, graf
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: biblio-1135227

RESUMO

Paracoccidioides spp. isolation from environmental samples is rare and hardly reproducible. Molecular techniques have facilitated the fungal detection. However, it can be still difficult. Some strategies to enhance the capacity of DNA detection have been adopted, including the analysis of soil samples belonging to the habitat of animals from which Paracoccidioides spp. have already been isolated, notably armadillo burrows. To date, the detection of Paracoccidioides spp. has not yet been reported from outbreak hotspots. Clusters and outbreaks of acute paracoccidioidomycosis (PCM), usually a more severe clinical form, have currently occurred in urban areas being associated to climate changes, deforestation, and great constructions. These occurrences potentially signalise the fungus' environmental niche, a riddle not yet solved. The authors performed an environmental investigation in a deeply disturbed area, after a highway construction in Rio de Janeiro, Brazil, where a recent outbreak of acute PCM occurred. Specific DNA sequences of Paracoccidioides brasiliensis were detected in shallow soil samples around the highway, reinforcing the association between the road construction and this PCM outbreak.


Assuntos
Animais , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/microbiologia , Tatus , DNA Fúngico/genética , Paracoccidioides/crescimento & desenvolvimento , Paracoccidioides/genética , Microbiologia do Solo , Brasil , Sequência de Bases , Análise de Sequência de DNA , Ecossistema
16.
Med Mycol Case Rep ; 24: 61-64, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31061785

RESUMO

Two cats infected by C. gattii, presented lesions on the nasal region and respiratory signs. Strains were typed as molecular type VGII, mating type alpha, MLST subtypes ST442 and ST185. Since Rio de Janeiro is known as an endemic area for C. neoformans VNI, these cases might be a warning for a possible emergence of C. gattii VGII in southeast Brazil.

17.
Fungal Genet Biol ; 129: 16-29, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30953839

RESUMO

A total of 476 European isolates (310 Cryptococcus neoformans var. grubii, 150 C. neoformans var. neoformans, and 16 C. gattii species complex) from both clinical and environmental sources were analyzed by multi-locus sequence typing. Phylogenetic and population genetic analyses were performed. Sequence analysis identified 74 sequence types among C. neoformans var. neoformans (VNIV), 65 among C. neoformans var. grubii (56 VNI, 8 VNII, 1 VNB), and 5 among the C. gattii species complex (4 VGI and 1 VGIV) isolates. ST23 was the most frequent genotype (22%) among VNI isolates which were mostly grouped in a large clonal cluster including 50% of isolates. Among VNIV isolates, a predominant genotype was not identified. A high percentage of autochthonous STs were identified in both VNI (71%) and VNIV (96%) group of isolates. The 16 European C. gattii species complex isolates analyzed in the present study originated all from the environment and all belonged to a large cluster endemic in the Mediterranean area. Population genetic analysis confirmed that VNI group of isolates were characterized by low variability and clonal expansion while VNIV by a higher variability and a number of recombination events. However, when VNI and VNIV environmental isolates were compared, they showed a similar population structure with a high percentage of shared mutations and the absence of fixed mutations. Also linkage disequilibrium analysis reveals differences between clinical and environmental isolates showing a key role of PLB1 allele combinations in host infection as well as the key role of LAC1 allele combinations for survival of the fungus in the environment. The present study shows that genetic comparison of clinical and environmental isolates represents a first step to understand the genetic characteristics that cause the shift of some genotypes from a saprophytic to a parasitic life style.


Assuntos
Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Genótipo , Filogenia , Animais , Microbiologia Ambiental , Europa (Continente) , Genética Populacional , Humanos , Região do Mediterrâneo , Tipagem de Sequências Multilocus , Técnicas de Tipagem Micológica
18.
Med Mycol ; 57(7): 864-873, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657975

RESUMO

Early diagnosis, efficient clinical support, and proper antifungal therapy are essential to reduce death and sequels caused by cryptococcosis. The emergence of resistance to the antifungal drugs commonly used for cryptococcosis treatment is an important issue of concern. Thus, the in vitro antifungal susceptibility of clinical strains from northern Brazil, including C. neoformans VNI (n = 62) and C. gattii VGII (n = 37), to amphotericin B (AMB), 5-flucytosine, fluconazole, voriconazole, and itraconazole was evaluated using the Etest and Vitek 2 systems and the standardized broth microdilution (CLSI-BMD) methodology. According to the CLSI-BMD, the most active in vitro azole was voriconazole (C. neoformans VNI modal MIC of 0.06 µg/ml and C. gattii VGII modal MIC of 0.25 µg/ml), and fluconazole was the least active (modal MIC of 4 µg/ml for both fungi). Modal MICs for amphotericin B were 1 µg/ml for both fungi. In general, good essential agreement (EA) values were observed between the methods. However, AMB presented the lowest EA between CLSI-BMD and Etest for C. neoformans VNI and C. gattii VGII (1.6% and 2.56%, respectively, P < .05 for both). Considering the proposed Cryptococcus spp. epidemiological cutoff values, more than 97% of the studied isolates were categorized as wild-type for the azoles. However, the high frequency of C. neoformans VNI isolates in the population described here that displayed non-wild-type susceptibility to AMB is noteworthy. Epidemiological surveillance of the antifungal resistance of cryptococcal strains is relevant due to the potential burden and the high lethality of cryptococcal meningitis in the Amazon region.


Assuntos
Antifúngicos/farmacologia , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Anfotericina B/farmacologia , Brasil , Técnicas de Laboratório Clínico , Criptococose/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Fúngica , Flucitosina/farmacologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Voriconazol/farmacologia
19.
PLoS Negl Trop Dis ; 12(7): e0006675, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30048450

RESUMO

BACKGROUND: Chromoblastomycosis (CBM) is a difficult-to-treat chronic subcutaneous mycosis. In Brazil, the main agent of this disease is Fonsecaea pedrosoi, which is phenotypically very similar to other Fonsecaea species, differing only genetically. The correct species identification is relevant since different species may differ in their epidemiologic aspects, clinical presentation, and treatment response. METHODOLOGY/PRINCIPAL FINDINGS: Partial sequencing of the internal transcribed spacer (ITS) was used to identify twenty clinical isolates of Fonsecaea spp. Their in vitro antifungal susceptibility was determined using the broth microdilution method, according to the M38-A2 protocol. Amphotericin B (AMB), flucytosine (5FC), terbinafine (TRB), fluconazole (FLC), itraconazole (ITC), ketoconazole (KTC), posaconazole (POS), voriconazole (VRC), ravuconazole (RVC), caspofungin (CAS), and micafungin (MFG) were tested. The association between ITC/TRB, AMB/5FC, and ITC/CAS was studied by the checkerboard method to check synergism. The available patients' data were correlated with the obtained laboratory results. Fonsecaea monophora (n = 10), F. pedrosoi (n = 5), and F. nubica (n = 5) were identified as CBM' agents in the study. TRB and VRC were the drugs with the best in vitro activity with minimal inhibitory concentrations (MIC) lower than 0.25 mg/L. On the other hand, FLC, 5FC, AMB, and MFG showed high MICs. The AMB/5FC combination was synergistic for three F. monophora strains while the others were indifferent. Patients had moderate or severe CBM, and ITC therapy was not sufficient for complete cure in most of the cases, requiring adjuvant surgical approaches. CONCLUSIONS/SIGNIFICANCE: F. monophora, the second most frequent Fonsecaea species in South America, predominated in patients raised and born in Rio de Janeiro, Brazil, without cerebral involvement in these cases. TRB, VRC, and the AMB/5FC combination should be further investigated as a treatment option for CBM.


Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Cromoblastomicose/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anfotericina B/farmacologia , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Brasil , Caspofungina , Cromoblastomicose/tratamento farmacológico , DNA Fúngico/genética , DNA Intergênico/genética , Equinocandinas/farmacologia , Feminino , Humanos , Itraconazol/farmacologia , Lipopeptídeos/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Voriconazol/farmacologia
20.
PLoS One ; 13(6): e0197841, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29883489

RESUMO

Cryptococcosis is considered endemic in Amazonas state, occurring more frequently in individuals with AIDS, who are predominantly infected by Cryptococcus neoformans molecular type VNI. Infections by Cryptococcus gattii VGII predominate in immunocompetent hosts from the American continent and are associated with outbreaks in North America, particularly the subtypes VGIIa and VGIIb, which are also present in the Brazilian Amazon region. Despite few environmental studies, several aspects of the molecular epidemiology of this disease in Amazonas remain unclear, including the limited use of multilocus sequence typing (MLST) to evaluate the genetic population structure of clinical isolates, mainly C. neoformans. Therefore, we used MLST to identify the sequence types of 38 clinical isolates of C. neoformans VNI and C. gattii VGII and used phylogenetic analysis to evaluate their genetic relationship to global isolates. Records of 30 patients were analyzed to describe the current scenario of cryptococcosis in the region and their associations with the different subtypes. Broth microdilution was also performed to determine the susceptibility profile to the antifungals amphotericin B, fluconazole and itraconazole. MLST identified that patients with HIV (n = 26) were exclusively affected by VNI strains with ST93, and among the VGII strains (n = 4), three STs (ST5, ST172 and the new ST445) were identified. An in-hospital lethality of 54% was observed in the HIV group, and there were no significant differences in the clinical aspects of the disease between the HIV and non-HIV groups of patients. In addition, all isolates were susceptible to the antifungals tested. Therefore, in Amazonas state, VNI isolates are a genetically monotypic group, with ST93 being highly important in HIV individuals.


Assuntos
Cryptococcus neoformans/classificação , Tipagem de Sequências Multilocus , Adulto , Idoso , Brasil/epidemiologia , Criptococose/epidemiologia , Cryptococcus neoformans/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Tipagem Micológica , Filogenia , Adulto Jovem
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