Avidez de anticorpos IgG específicos como marcadores de infecção primária recente pelo Toxoplasma gondii

• Autor(a) principal: Camargo, Mário E.
• Data de Publicação: 1991
• Outros Autores: Silva, Sueli M. da, Leser, Paulo G., Granato, Celso H.
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Revista do Instituto de Medicina Tropical de São Paulo
• Texto Completo: https://www.revistas.usp.br/rimtsp/article/view/28821
• topic: Toxoplasma gondii; Infecção primária; IgG

For serologically characterizing a recent primary toxoplasma infection, the low avidity of IgG specific antibodies was studied. Avidity was evaluated as the decrease of IgG antibody titers in ELISA after treating plates with 6 M urea, as a dissociating solution of low avidity antigen-antibody complexes. Sixty nine serum samples were studied, presenting characteristic patterns of recent, transitional or chronic toxoplasmosis. Serological patterns were determined according to results of IgG and IgM immunofluorescence, IgM-capture, and hemagglutination tests. Twenty three serum samples from each of the referred patterns I,II and III were titrated. For chronic toxoplasmosis infections, which presented a serological pattern III, observed decrease of titers was 3% ± 3%. For pattern I recent toxoplasmosis sera it was 34% ± 12%, and for transition pattern II, 12% ±9%. Thus, a low avidity of IgG specific antibodies can be applicable for the diagnosis of a recent toxoplasmosis infection.