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.
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/farmacologiaRESUMO
BACKGROUND: Although dermatophytes are considered the major cause of onychomycosis, many reports have incriminated non-dermatophyte moulds and yeasts in the disease's etiology. Successive Trichosporon isolation from onychomycosis has led to the genus being suspected as a nail primary pathogen. OBJECTIVE: To determine the prevalence of Trichosporon isolation in onychomycosis patients who attended a mycology diagnostic service in Rio de Janeiro, Brazil, between January 2003 and December 2006. The study also includes a worldwide review on Trichosporon isolation prevalence in ungueal disease, emphasizing T. ovoides. METHODS: This retrospective study was conducted with the support of staff from the Mycology Laboratory at the Dermatological Service of Rio de Janeiro's Santa Casa da Misericórdia (MLDS). RESULTS: Mycological analysis provided positive results equaling 47/5036 (0.93%) for Trichosporon spp.; obtained mainly as a single agent (72.35%), and from mixed cultures (27.65%; X2= 6.397; p= 0.018). The great majority belongs to the T. ovoides species (91.5%; n=43), obtained as a single isolate (74.41%; n= 32/43; X2 = 7.023; p= 0.014). CONCLUSIONS: Although T. ovoides is classically associated as an etiologic agent of white piedra, this study highlights its potential as a human nail disease pathogen. Our study opens doors for future epidemiologic and virulence factors aimed at determining whether T. ovoides is an important causative agent of onychomycosis in Brazil.
Assuntos
Onicomicose/epidemiologia , Onicomicose/microbiologia , Trichosporon/isolamento & purificação , Trichosporon/patogenicidade , Idoso , Brasil/epidemiologia , Contagem de Colônia Microbiana , Feminino , Dermatoses do Pé/microbiologia , Dermatoses da Mão/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos RetrospectivosRESUMO
Abstract BACKGROUND: Although dermatophytes are considered the major cause of onychomycosis, many reports have incriminated non-dermatophyte moulds and yeasts in the disease’s etiology. Successive Trichosporon isolation from onychomycosis has led to the genus being suspected as a nail primary pathogen. OBJECTIVE: To determine the prevalence of Trichosporon isolation in onychomycosis patients who attended a mycology diagnostic service in Rio de Janeiro, Brazil, between January 2003 and December 2006. The study also includes a worldwide review on Trichosporon isolation prevalence in ungueal disease, emphasizing T. ovoides. METHODS: This retrospective study was conducted with the support of staff from the Mycology Laboratory at the Dermatological Service of Rio de Janeiro’s Santa Casa da Misericórdia (MLDS). RESULTS: Mycological analysis provided positive results equaling 47/5036 (0.93%) for Trichosporon spp.; obtained mainly as a single agent (72.35%), and from mixed cultures (27.65%; X2= 6.397; p= 0.018). The great majority belongs to the T. ovoides species (91.5%; n=43), obtained as a single isolate (74.41%; n= 32/43; X2 = 7.023; p= 0.014). CONCLUSIONS: Although T. ovoides is classically associated as an etiologic agent of white piedra, this study highlights its potential as a human nail disease pathogen. Our study opens doors for future epidemiologic and virulence factors aimed at determining whether T. ovoides is an important causative agent of onychomycosis in Brazil.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Trichosporon/isolamento & purificação , Trichosporon/patogenicidade , Onicomicose/microbiologia , Onicomicose/epidemiologia , Brasil/epidemiologia , Contagem de Colônia Microbiana , Prevalência , Estudos Retrospectivos , Dermatoses do Pé/microbiologia , Dermatoses da Mão/microbiologiaRESUMO
Cryptococcosis is a human fungal infection of significant mortality and morbidity, especially in the meningoencephalitis form. Cryptococcosis is distributed worldwide and its agents, C. neoformans and C. gattii, present eight major molecular types-VNI-VNIV and VGI-VGIV respectively. The primary cryptococcosis caused by molecular type VGII (serotype B, MAT alpha) prevails in immunocompetent patients in the North and Northeast of Brazil, revealing an endemic regional pattern to this molecular type. Since 1999, C. gattii VGII has been involved in an ongoing outbreak in Canada, and is expanding to the Northwest of the United States, two temperate regions. Exposure to propagules dispersed in the environment, related to various organic substrates, mainly decomposing wood in and around dwellings, initiates the infection process. The present study investigated the presence of the agents of cryptococcosis in dust from dwellings in the upper Rio Negro, municipality of Santa Isabel do Rio Negro in Amazonas state. Indoor dust was collected from 51 houses, diluted and plated on bird seed agar. Dark brown colonies were identified phenotypically, and genotypically by URA5 restriction fragment length polymorphism analysis and multilocus sequence typing (MLST). The mating type was identified using pheromone-specific primers. Three of the 51 houses were positive for C. gattii molecular type VGII, MATα and MATa, showing a high prevalence of this agent. MLST studies identified eight subtypes, VGIIb (ST7), VGIIa (ST20), (ST5) and 5 new subtypes unique to the region. For the first time in the state of Amazonas, C. gattii VGII MATα and MATa were isolated from the environment and correlates with endemic cryptococcosis in this state. This is the first description of MLST subtypes on environmental isolates in the Brazilian Amazon, indicating domiciliary dust as a potential source for human infection with different subtypes of C. gattii VGII MATα and MATa.
Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Cryptococcus gattii/classificação , Cryptococcus gattii/isolamento & purificação , Poeira , Clima Tropical , Brasil , Cryptococcus gattii/genética , Geografia , Humanos , Tipagem de Sequências Multilocus , Fenótipo , FilogeniaRESUMO
De acordo com o Guia para Operação de Centros de Recursos Biológicos da Organização para Cooperação e Desenvolvimento Econômico (OCDE), os Centros de Recursos Biológicos devem dispor os dados descritivos do e sua origem ao Global Biological Resource Center Network. Essa deliberação ratifica a preocupação da validação de ferramentas utilizadas no tratamento de dados pelas coleções e laboratórios prestadores de serviços no escopo indireto de suas rotinas, visando à qualidade. A avaliação do Sistema de Banco de Dados da Coleção de Culturas de Fungos de Referência (INFOGER_FUNGOS), do Instituto Nacional de Controle de Qualidade em Saúde (INCQS), de acordo com a norma ISO/IEC nº 17.025:2005, estabelece um marco na qualidade e integridade das informações, economizando tempo na elaboração das estruturas do sistema permitindo ao profissional diretamente envolvido com a coleção e suas particularidades seja seu administrador. Este trabalho teve como objetivo demonstrar um método de avaliação de um sistema de gerenciamento de dados no cumprimento de sua finalidade atingindo níveis de qualidade satisfatórios. Ele servirá de modelo para avaliações de sistemas utilizados em coleções de micro-organismos dentro das normas da Qualidade e Acreditação de seus serviços e produtos, e colaborar no estabelecimento de padrão de dados baseado em experiências brasileiras, adaptado e estendido a modelos existentes.
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Fungos , Gestão da Informação , Sistemas de InformaçãoRESUMO
De acordo com o Guia para Operação de Centros de Recursos Biológicos da Organização para Cooperação e Desenvolvimento Econômico (OCDE), os Centros de Recursos Biológicos devem dispor os dados descritivos do e sua origem ao Global Biological Resource Center Network. Essa deliberação ratifica a preocupação da validação de ferramentas utilizadas no tratamento de dados pelas coleções e laboratórios prestadores de serviços no escopo indireto de suas rotinas, visando à qualidade. A avaliação do Sistema de Banco de Dados da Coleção de Culturas de Fungos de Referência (INFOGER_FUNGOS), do Instituto Nacional de Controle de Qualidade em Saúde (INCQS), de acordo com a norma ISO/IEC nº 17.025:2005, estabelece um marco na qualidade e integridade das informações, economizando tempo na elaboração das estruturas do sistema permitindo ao profissional diretamente envolvido com a coleção e suas particularidades seja seu administrador. Este trabalho teve como objetivo demonstrar um método de avaliação de um sistema de gerenciamento de dados no cumprimento de sua finalidade atingindo níveis de qualidade satisfatórios. Ele servirá de modelo para avaliações de sistemas utilizados em coleções de micro-organismos dentro das normas da Qualidade e Acreditação de seus serviços e produtos, e colaborar no estabelecimento de padrão de dados baseado em experiências brasileiras, adaptado e estendido a modelos existentes. (AU)
Assuntos
Fungos , Sistemas de Informação , Gestão da InformaçãoRESUMO
A yeast strain isolated from feather waste from a chicken processing plant was identified as Candida parapsilosis by biochemical tests and morphological studies. The yeast was able to grow in phosphate-buffered saline supplemented with 1% native feather as the sole carbon and nitrogen source. A keratin substrate was obtained from the feathers by dimethylsulphoxide extraction. A 20-fold concentrated culture supernatant from Candida parapsilosis grown on feathers was analysed by SDS-PAGE electrophoresis containing either 1% gelatin or 1% keratin as copolymerised substrates. The presence of a single band with an approximate molecular mass of 60 kDa with gelatinolytic and keratinolytic activities was observed. This proteolytic activity was fully inhibited by phenylmethylsulphonyl fluoride. These results suggest that the extracellular enzyme belongs to the serine peptidase class. This is the first report of an extracellular serine peptidase produced by C. parapsilosis with keratinolytic activity. The role of this enzyme in yeast-host interactions is discussed.
Assuntos
Candida/enzimologia , Espaço Extracelular/enzimologia , Peptídeo Hidrolases/metabolismo , Serina Proteases/metabolismo , Animais , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Galinhas , Plumas/metabolismo , Gelatina/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Resíduos Industriais , Queratinas/metabolismo , Peso Molecular , Onicomicose/enzimologia , Onicomicose/microbiologia , Peptídeo Hidrolases/química , Fluoreto de Fenilmetilsulfonil/farmacologia , Serina Proteases/química , Inibidores de Serina Proteinase/farmacologia , Especificidade por SubstratoRESUMO
The Trichosporon genus is constituted by many species, of which Trichosporon ovoides and Trichosporon inkin are the causative agents of white piedra. They can cause nodules in genital hair or on the scalp. At present, Brazilian laboratory routines generally do not include the identification of the species of Trichosporon genus, which, although morphologically and physiologically distinct, present many similarities, making the identification difficult. The aim of this study was to identify the aetiological agents at the species level of white piedra from clinical specimens. Therefore, both the macro and micro morphology were studied, and physiological tests were performed. Trichosporon spp. was isolated from 10 clinical samples; T. ovoides was predominant, as it was found in seven samples, while T. inkin was identified just in two samples. One isolate could not be identified at the species level. T. inkin was identified for the first time as a white piedra agent in the hair shaft on child under the age of 10.
Assuntos
Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Piedra/microbiologia , Dermatoses do Couro Cabeludo/microbiologia , Trichosporon/classificação , Técnicas de Tipagem Micológica , Estudos Retrospectivos , Trichosporon/química , Trichosporon/citologiaRESUMO
In order to study the infectious agents causing human disseminated cryptococcosis in the state of Pará, North Brazil, 56 isolates of Cryptococcusspp. (54 isolated from cerebral spinal fluid and two from blood cultures) from 43 cases diagnosed between 2003-2007 were analysed. The species were determined through morphological and physiological tests and genotypes were determined by URA5-RFLP and PCR-fingerprinting (wild-type phage M13). The following species and genotypes were identified: Cryptococcus neoformans VNI (28/56, 50 percent), Cryptococcus gattii VGII (25/56, 44.64 percent) and C. gattii VGI (3/56, 5.26 percent). The genotype VNI occurred in 12 out of 14 HIV-positive adults, whereas the genotype VGII occurred in 11 out of 21 HIV-negative adults (p < 0.02, OR = 6.6 IC95 percent 0.98-56.0). All patients less than 12 years old were HIV negative and six cases were caused by the VGII genotype, one by the VGI and one by VNI. Therefore, endemic primary mycosis in HIV-negative individuals, including an unexpectedly high number of children, caused by the VGII genotype deserves further study and suggests the need for surveillance on cryptococcal infection in the state of Pará, Eastern Amazon.