Assuntos
Histoplasmose/diagnóstico , Pneumopatias Fúngicas/diagnóstico , Adulto , Animais , Animais Selvagens/microbiologia , Argentina , Columbidae/microbiologia , Diagnóstico Diferencial , Fezes/microbiologia , Hepatomegalia/etiologia , Histoplasmina/imunologia , Histoplasmose/complicações , Histoplasmose/diagnóstico por imagem , Histoplasmose/patologia , Histoplasmose/transmissão , Humanos , Hipergamaglobulinemia/etiologia , Imunodifusão , Testes Intradérmicos , Pneumopatias Fúngicas/complicações , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/patologia , Pneumopatias Fúngicas/transmissão , Masculino , Ratos/microbiologia , Esplenomegalia/etiologia , Tomografia Computadorizada por Raios XRESUMO
Histoplasma capsulatum is a dimorphic pathogenic fungus that causes a wide spectrum of disease when mycelial fragments are inhaled. Resistance to H. capsulatum is dependent on cellular immunity mediated by T cells and macrophages. Here we standardized the production of extracts containing cell-free antigens (CFAgs) and observed their efficacy in evaluating cellular immunity during murine histoplasmosis. CFAgs induced a more potent delayed-type hypersensitivity (DTH) response in H. capsulatum-infected mice than did histoplasmin-a classical antigen. This DTH response to CFAgs is able to determine the immune status of infected mice and to predict their death. Moreover, CFAgs stimulated spleen cells from immune mice to produce higher amounts of gamma interferon (IFN-gamma) in vitro. Finally, immunization with CFAgs protected against a lethal inoculum of H. capsulatum. These results demonstrate that CFAgs may be useful for the evaluation of cellular immune response and as a potential source for the development of a vaccine against histoplasmosis.
Assuntos
Antígenos de Fungos/administração & dosagem , Antígenos de Fungos/imunologia , Histoplasma/imunologia , Histoplasmina/imunologia , Histoplasmose/imunologia , Histoplasmose/prevenção & controle , Animais , Antígenos de Fungos/isolamento & purificação , Histoplasma/patogenicidade , Histoplasmina/administração & dosagem , Histoplasmose/microbiologia , Histoplasmose/mortalidade , Humanos , Hipersensibilidade Tardia , Imunidade Celular , Imunização , Interferon gama/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos CBA , Baço/citologia , Baço/imunologiaRESUMO
Since Paracoccidioides brasiliensis and Histoplasma capsulatum are known to be present in similar environments, there have been many epidemiologic investigations regarding the prevalences of these two organisms. However, cross-reactivity can occur in paracoccidioidin and histoplasmin skin tests, and this usually results in the overestimation of the prevalence of P. brasiliensis. The prevalence of infection with P. brasiliensis was evaluated in a cross-sectional study of 298 asymptomatic school children in the Brazilian Amazon region (Mato Grosso State). In this investigation, the reactivity of children to two different P. brasiliensis antigen preparations, paracoccidioidin and a purified 43-kD glycoprotein (gp43), was compared with or without the co-administration of histoplasmin. In the group of individuals receiving paracoccidioidin who had a positive histoplasmin skin test result, the prevalence of exposure to P. brasiliensis was 44% (16 of 36). This reactivity to P. brasiliensis was significantly higher than that observed in other groups, which ranged from 4% to 6% (P < 5 x 10(-4) for each). Overall prevalence was 4.6% (95% confidence interval = 2.5-7.7%). These data suggest that gp43 provides a better estimate of exposure to P. brasiliensis when the co-administration of histoplasmin is desired.
Assuntos
Antígenos de Fungos/análise , Proteínas Fúngicas , Glicosaminoglicanos/análise , Histoplasmina/análise , Paracoccidioides/imunologia , Paracoccidioidomicose/epidemiologia , Adolescente , Brasil/epidemiologia , Criança , Feminino , Proteínas Fúngicas/imunologia , Glicoproteínas/imunologia , Glicosaminoglicanos/imunologia , Histoplasmina/imunologia , Humanos , Testes Intradérmicos , Masculino , Paracoccidioidomicose/diagnóstico , Paracoccidioidomicose/imunologia , Prevalência , Testes CutâneosRESUMO
Paracoccidioidomycosis is a systemic mycoses caused by Paracoccidioides brasiliensis, a dimorphic fungus that infects man through respiratory ducts. It has been accepted that its ecological niche is located in the soil and plants of subtropical forests of Latin America. The Province of Corrientes is located at the northeastern border of Argentina, in a subtropical area where important environmental modifications have been introduced in the last decade as consequence of damming the Paranà river at Yacyretà, one of the biggest hydroelectric dams in the world. Since there are no data on human infection provoqued by this fungal agent in Corrientes, the purpose of this study was to obtain information at present time about infection indexes and to assess if environmental changes introduced in the area could impact on the epidemiology of the disease. Skin tests with paracoccidioidin and histoplasmin were performed on 455 persons of both sexes, from 1 to 73 years of age, who live permanently in the area and voluntarily accepted to be included in the study. Both antigens were employed at the same time in order to evaluate crossed type reactions. Of the 455 persons, 52 (39 males-13 females) were reactive to paracoccidioidin (11.4%), with an increasing prevalence with age. According to previous data, these results would indicate an increase in the index of human infection by P. brasiliensis, and this may be related to the important changes in climatic and environmental conditions introduced in the area in the last years.
Assuntos
Meio Ambiente , Paracoccidioidomicose/epidemiologia , Clima Tropical , Adolescente , Adulto , Idoso , Argentina/epidemiologia , Criança , Pré-Escolar , Feminino , Proteínas Fúngicas/imunologia , Histoplasmina/imunologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Paracoccidioidomicose/diagnóstico , Testes CutâneosRESUMO
OBJECTIVE: Histoplasma capsulatum infection is considered to be endemic in the West Indies. Nevertheless, few epidemiologic studies have been conducted in this area. The histoplasmin skin test reflects the frequency of asymptomatic forms of histoplasmosis. We studied the prevalence of positive skin tests in a population of the French West Indies (Martinique). MATERIALS AND METHODS: Forty one patients (24 females and 17 males), age range 29 to 90 years, were tested for histoplasmin skin sensitivity between August and October 1997, in the department of dermatology of Fort de France (French West Indies). Patients with immunosuppression or personal history of histoplasmosis were excluded. RESULTS: Five patients had a positive skin test (12 p. 100). No significative association was found between a positive skin test and diabetes, rural occupations or exposure to bats. DISCUSSION: Despite the small number of cases, related with difficulties in obtaining histoplasmin, our study showed a sensitivity level similar to medium endemic areas of the USA. The positive skin test rate is much higher than the rate reported before in West Indies, in a sample of the population under 25 years of age.
Assuntos
Doenças Endêmicas , Histoplasmina , Histoplasmose/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Histoplasmina/imunologia , Histoplasmose/diagnóstico , Histoplasmose/imunologia , Humanos , Testes Intradérmicos , Masculino , Martinica , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Pele/imunologiaRESUMO
The present work was undertaken to obtain epidemiological data on the extent and distribution of Histoplasma capsulatum var. capsulatum and Paracoccidiodes brasiliensis diseases in the Vipos, La Toma and Choromoro areas. Skin test surveys with histoplasmin and paracoccidioidin were carried out in the permanent human population of those localities. Mycological sputum studies and serological tests were performed to skin test reactors to determine if there were signs or symptoms of active mycotic disease. La Toma and Choromoro are highly prevalent areas of histoplasmosis (>30% the histoplasmin positive individuals) whereas Vipos can be relatively considered a highly prevalent area (between 20-30% the histoplasmin reactors) according to the normally accepted range used to define an endemic disease [2]. Early Histoplasma capsulatum infection (<10 years old) is reported for Vipos and Choromoro. La Toma has the highest rate of previous exposure to P. brasiliensis detected in the studied area (10.2%). Vipos residents are not infected with P. brasiliensis.
Assuntos
Histoplasmose/epidemiologia , Paracoccidioidomicose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antifúngicos/sangue , Argentina/epidemiologia , Criança , Pré-Escolar , Proteínas Fúngicas/imunologia , Histoplasma/imunologia , Histoplasma/isolamento & purificação , Histoplasmina/imunologia , Humanos , Lactente , Pessoa de Meia-Idade , Paracoccidioides/imunologia , Paracoccidioides/isolamento & purificação , Prevalência , Testes Cutâneos , Escarro/microbiologiaRESUMO
Introducción: El empleo de un antígeno parcialmente purificado denominado complejo polisacárido-proteína desproinizado de Histoplasma capsulatum (CPPD-Histo), utilizado para discriminar la histoplasmosis de diversas micosis pulmonares y otras enfermedades respiratorias en métodos inmunodiagnósticos de alta sensibilidad, ha sido motivo de estudio desde hace años por nuestro grupo de investigación: Objetivo: En este trabajo se planteó conocer la ubicación celular preferencial del antígeno CPPD-Histo, en las diferentes formas y estructuras de las fases micelial y levaduriforme del hongo. Material y métodos: El estudio se desarrolló mediante inmunolocalización con marcaje de oro coloidal para microscopia electrónica, usando anticuerpos primarios CPPD-Histo específicos. Resultados y discusión: La localización en microscopia electrónica mostró mayor concentración del CPPD-Histo en las zonas de mayor grosor de la capa externa de la pared celular de las proyecciones digitiformes de macroconidios, poco marcaje en pared celular de hifas, y una distribución dispersa de la marca en las levaduras. Conclusión: La pared celular de los macroconidios de la fase micelial del hongo es la estructura fúngica con mayor concentración del antígeno CPPD-Histo
Assuntos
Complexo Antígeno-Anticorpo , Coloide de Ouro , Histoplasma/imunologia , Histoplasma/ultraestrutura , Histoplasmina , Histoplasmina/química , Histoplasmina/imunologia , Micelas , Microscopia Eletrônica , Relação Estrutura-Atividade , Testes Imunológicos/métodosRESUMO
O estudo envolve a comparaçäo entre o antigeno polissacaridico de Histoplasma capsulatum com a histoplasmina classica em inquerito epidemiologico, atraves de provas intradermicas de hipersensibilidade do tipo tardio, realizado em 115 individuos da regiäo de Santo Amaro. Os resultados revelaram 46 por cento de provas positivas com a histoplasmina classica e 51,30 por cento de resultados positivos com o antigeno polissacaridico em sua maior concentraçäo. A principal conclusao da pesquisa: e possível utilizar o antigeno polissacaridico como histoplasmina, em substituiçäo ao antigeno filtrado
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Histoplasmina/imunologia , Hipersensibilidade Tardia , Polissacarídeos/imunologia , Brasil , Testes Intradérmicos/métodosRESUMO
Immunologic and occupational aspects of the susceptible population exposed to Histoplasma capsulatum, the causative agent of histoplasmosis were analyzed in the Mexican State of Guerrero. Three areas were studied, Juxtlahuaca, Olinala, and Coyuca; in the first two, their populations refer contact with bat guano and/or avian excreta, which contain nutrients for fungal growth, while the Coyuca population referred no contact with the above mentioned excreta. Previous infection with H. capsulatum was determined by histoplasmin-skin test, and the response was higher in men than in women (93.87, 85.71, and 6.6% for men, and 78.94, 66.6, and 0% for women) in Juxtlahuaca, Olinala, and Coyuca, respectively. Labor activities related to a persistent contact with the fungus were considered as an occupational risk factor, histoplasmin-skin test reached 88.57 and 36.36% of positive response in individuals with high and low risk activities. A high percentage of histoplasmin responses was observed in subjects with constant contact with H. capsulatum, such as, cave-tourist guides, peasants, and game-cock handlers, and generally they developed the largest diameter of skin reactions. Genetic risk factor was determined by studying the gene frequency of the Major Histocompatibility Complex antigens in a sample of individuals and their degree relatives in Juxtlahuaca, Olinala, and Coyuca. Significant differences were found for HLA-B22 and B17 antigens in Juxtlahuaca, and for HLA-B22 in Olinala, in comparison to the usual gene frequency observed in the normal Mexican population. HLA results were important, considering that HLA-B22 was previously found to be possibly related to pulmonary histoplasmosis in Guerrero.
Assuntos
Histoplasmose/epidemiologia , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Animais , Aves , Quirópteros , Feminino , Frequência do Gene , Antígenos HLA-A/sangue , Antígenos HLA-A/genética , Antígenos HLA-B/sangue , Antígenos HLA-B/genética , Antígenos HLA-C/sangue , Antígenos HLA-C/genética , Teste de Histocompatibilidade , Histoplasma/imunologia , Histoplasma/patogenicidade , Histoplasmina/imunologia , Histoplasmose/genética , Histoplasmose/imunologia , Humanos , Masculino , México/epidemiologia , Doenças Profissionais/genética , Doenças Profissionais/imunologia , Exposição Ocupacional/estatística & dados numéricos , Fatores de Risco , Saúde da População Rural , Fatores Sexuais , Testes CutâneosRESUMO
This work was planned by taking into account all the knowledge accumulated from the immunological study of paracoccidioidomycosis. It aimed at comparing a polysaccharide antigen from Histoplasma capsulatum to a classic histoplasmin with the help of intradermal tests of delayed type of hypersensitivity. Tests were applied to 115 individuals in Santo Amaro, a town in the State of São Paulo. Positive results using classic histoplasmin were obtained in 46.0% cases whereas positive results using the polysaccharide antigen at its highest concentration were obtained in 51.30% cases. The major conclusion in this investigation is that it is possible to use the polysaccharide antigen as histoplasmin instead of the filtrate antigen.