[Reactivity of a purified antigen of Paracoccidioides brasiliensis with paracoccidioidomycosis and histoplasmosis sera].

The immunoelectrophoretic reactivity of a "crude" and a "purified" antigens of Paracoccidiodes brasiliensis against the sera of confirmed cases of paracoccidioidomycosis and histoplasmosis was evaluated. The "crude" antigen revealed precipitating antibodies in both the homologous and the heterologous human sera; the number of precipitating systems being higher with the former. The "purified" antigen reacted only with the homologous sera. It is postulated that the use of such "purified" antigen may significantly reduce the non specificity of the serologic tests in the immunodiagnosis of paracoccidioidomycosis.