title: Immunological assays employed for the elucidation of an histoplasmosis outbreak in São Paulo, SP.
abstract: 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.
authors.affiliation: Laboratório de Imunodiagnóstico das Micoses Centro de Imunologia Instituto Adolfo Lutz São PauloSP Brazil Laboratório de Imunodiagnóstico das Micoses, Centro de Imunologia, Instituto Adolfo Lutz, São Paulo, SP, Brazil. ; Programa de Pós-Graduação em Ciências Coordenadoria de Controle de Doenças Secretaria de Estado da Saúde de São Paulo São PauloSP Brazil Programa de Pós-Graduação em Ciências, Coordenadoria de Controle de Doenças, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brazil.
authors.forename: Angela Noronha
authors.initials: AN
authors.lastname: Passos
authors.affiliation: Laboratório de Imunodiagnóstico das Micoses Centro de Imunologia Instituto Adolfo Lutz São PauloSP Brazil Laboratório de Imunodiagnóstico das Micoses, Centro de Imunologia, Instituto Adolfo Lutz, São Paulo, SP, Brazil.
authors.forename: Valdelene Sayuri
authors.initials: VS
authors.lastname: Kohara
authors.affiliation: Laboratório de Micologia Médica Instituto de Medicina Tropical Universidade de São Paulo São PauloSP Brazil Laboratório de Micologia Médica, Instituto de Medicina Tropical, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Roseli Santos
authors.initials: RS
authors.lastname: de Freitas
authors.affiliation: Laboratório de Imunodiagnóstico das Micoses Centro de Imunologia Instituto Adolfo Lutz São PauloSP Brazil Laboratório de Imunodiagnóstico das Micoses, Centro de Imunologia, Instituto Adolfo Lutz, São Paulo, SP, Brazil. ; Programa de Pós-Graduação em Ciências Coordenadoria de Controle de Doenças Secretaria de Estado da Saúde de São Paulo São PauloSP Brazil Programa de Pós-Graduação em Ciências, Coordenadoria de Controle de Doenças, Secretaria de Estado da Saúde de São Paulo, São Paulo, SP, Brazil.
authors.forename: Adriana Pardini
authors.initials: AP
authors.lastname: Vicentini
mesh_terms: D000293:Adolescent; D000328:Adult; D000908:Antibodies, Fungal / Q000097:blood*; D001938:Brazil / Q000453:epidemiology; D003955:Diagnostic Tests, Routine / Q000379:methods*; D004196:Disease Outbreaks; D005260:Female; D006658:Histoplasma / Q000276:immunology*; D006660:Histoplasmosis / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D008828:Microbiological Techniques / Q000379:methods*; D012680:Sensitivity and Specificity
chemical_list: D000908:Antibodies, Fungal
keywords: Histoplasma; double immunodiffusion; histoplasmosis; immunoassay; immunoblotting