Sérologie de la toxoplasmose : comparaison de deux techniques : microplaque Platelia® (Biorad) et automate Liaison® (Diasorin) étu de de l'avi dite des anticorps IgG anti-toxoplasmiques

The serological diagnosis of toxoplasmosis is especially based on the measurement of Toxoplasma-specffic immunoglobulin IgG and IgM: the determination of the IgG avidity index contributes to date the seroconversion. 393 serums samples were separated in 6 groups: negative sera, past toxoplasmosis, past toxoplasmosis with persistance of IgM, séroconversions, recently acquired toxoplasmosis and reactivations, were tested in IgG and IgM with two methods: a manual one. Platelia® Biorad and an automatised one, Liaison® system Diasorin, in comparison with AxSYM® and Vidas®. When serological interpretation is difficult, it's possible to determinate the IgG avidity index. 270 sera were also tested in avidity with the same methods. Our study shows that results obtained with Platelia® and Liaison® system are similar to Vidas® regarding the antibodies kinetics. This study confirms that a high avidity index of IgG excludes a recently acquired infection with Toxoplasma gondii. The combination of different assays improves the serological interpretation.