Resumo
Several reports showed outbreaks of histoplasmosis acquired while bat-inhabited caves were visited by tourists, miners or researchers. We evaluated the performance of double immunodifusion (DI) and immunoblotting (IB) assays, employed for the histoplasmosis outbreak elucidation occurred in Vale do Paraíba, São Paulo. The existence of epidemiologic link, four patients with clinical signs suggestive of histoplasmosis and mycological confirmation has made that all 35 individuals involved to the cave visit were subjected to serological evaluation. By DI, we observed reactivity against H. capsulatum antigen in a single serum examined nearly 20 days after exposure to fungal propagules. On the other hand, IB showed reactivity against H and M fractions in 50% of samples evaluated. The analysis of the second sample batch, collected two months after the exposure showed that 96.7% were reactive by DI with antibodies titers ranging from 1 to 16 and 100% of reactivity against H and M fractions, by IB, suggesting an acute infection. The analysis of the overall agreement between the methods showed to be reasonable (κ = 0.37). This study confirms the importance and efficacy of more sensitive methodologies, such as IB assay, to early elucidation of disease, especially in cases of patients without mycological information.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Anticorpos Antifúngicos/sangue , Surtos de Doenças , Testes Diagnósticos de Rotina/métodos , Histoplasma/imunologia , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Técnicas Microbiológicas/métodos , Brasil/epidemiologia , Imunoensaio/métodos , Sensibilidade e EspecificidadeResumo
The recombinant protein MSP5 has been established as an important antigen for serological diagnosis of Anaplasma marginale by enzyme-linked immunosorbent assay (ELISA). However, due to the high cost of specialized equipment, this technique is not accessible to all laboratories, especially in developing countries in areas where the disease is endemic. The present study describes the standardization of a latex agglutination test (LAT) to detect antibodies against A. marginale based on recombinant MSP5. Compared with indirect enzyme-linked immunosorbent assay (iELISA), the relative sensitivity and specificity of the LAT were 95.21% and 91.86% respectively, with an almost perfect agreement between tests (kappa index = 0.863). These results can be considered important for the serological diagnosis of A. marginale, as they indicate that the test represents a rapid and low cost alternative to ELISA.(AU)
Assuntos
Animais , Bovinos , Anaplasma marginale/imunologia , Anaplasmose/diagnóstico , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias , Proteínas da Membrana Bacteriana Externa , Doenças dos Bovinos/diagnóstico , Testes Diagnósticos de Rotina/métodos , Anaplasma marginale/genética , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Testes de Fixação do Látex/métodos , Proteínas Recombinantes , Proteínas Recombinantes/genética , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Medicina Veterinária/métodosResumo
The immunohistochemistry standardization for bovine viral diarrhea virus (BVDV) diagnostic was described. The formalin-fixed tissue samples from a heifer with mucosal disease were used as positive control. The validation of the first phase results was performed using samples from an aborted fetus and a calf infected with reference strains of BVDV. The best results were seen using monoclonal antibodies and a commercial kit consisting of labelled streptavidin biotin (LSAB) reagents and the diaminobenzidine (DAB) substrate-chromogen reagent. The immunohistochemistry demonstrated to be an useful method for routine diagnosis for the controll and detection of BVDV infection.(AU)