[Toxoplasmosis: comparative serological diagnosis (direct agglutination, complement fixation, hemagglutination inhibition tests) in order to attempt to clarify the diverse periods of infection in man].

Large diffusion of human toxoplasmotic infection and consequent injuries that, sometimes, occur in pregnancy and to the newborn, have been and are principal stimulus to study and to set several diagnostic means to specify, directly or indirectly, acute infection and acquired immunity. Serological methods are, at least till now, the best diagnostic means; among these, we have selected 3 methods: IHA (Behring), CF (I.S.M.) and DA (Bio-Mérieux); with which have been tested 125 sera (selected randomly). Obtained results have been elaborated statistically according to some interpretative perspectives which have been considered the most significant. Da test, that had a propensity to understimulation of serum-positive cases, would show a good sensibility about acute or recent infections and would be positive more difficulty about past infections. IHA test, on the contrary, that showed the greatest percentage of erroneously positive results, had, on the whole, a opposite propensity, but it would seem, with some reservations, also adaptable to the search of acute infections. CF test, rather complicated and long, would seem most versatile of three tests fitting well both to the search of past immunity and to serological diagnosis of acute infection, thanks to the new TTE antigen use.