Significance of the complement fixation reaction in the diagnosis of the acute phase of lymphatic toxoplasmosis

: In a group of 300 sera of subjects with clinically suspect nodular toxoplasmosis the authors tested by the IgM ELISA reaction in the reverse order the importance of the complement-fixation reaction for assessment of the acute stage of the infection. In view of the revealed prolonged detection of IgM antibodies the authors used quantitative evaluation of the reaction; they consider based on a probability pattern of antibody response coefficients of 10 and above important for differentiation of a recent infection. For the suggested method of evaluation it was confirmed that low CFR titres (1:8, 1:16, 1:32) imply usually (89.5%) latent infection, titres of 1:64 chronic (42.8%) and latent infection (57.2%); in no instance onset of the disease was involved. From the titre of 1:128 onwards there is a proportional increase of the probable detection of acute infections (titre 1:1024 as much as 72.7%. However, even high titres are not unequivocal evidence of recent infection. In view of the equivocal interpretation of results of the CFR the authors recommend for assessment of the acute stage of the nodular form of toxoplasmosis examination of the suspect subject by the CFR and in case of a medium or high level assessment of IgM by the ELISA method focused on the level and dynamics of the coefficient.