Aims: To study the predictive value of 9 non-specific signs for congenital toxoplasmosis.
Method: The work was carried out as a prospective study comparing non-specific signs in 22 fetuses infected with toxoplasmosis and 59 fetuses free of the disease.
Results: Four of the nine parameters were found to be statistically higher in the group of infected fetuses. These are the level of leucocytes (p < 0.05) gamma glutamyl transferase (p < 0.001) total M immunoglobulin (p < 0.0001) and C4 fraction of complement (p < 0.0001). This last sign which is non-specific for infection has never been looked at until now in congenital toxoplasmosis but is seems to be of great importance because its sensitivity is much greater than of all the other parameters that have been used up till now (81%) and the positive predictive value is excellent (72%). On the other hand the value of a raised leucocyte count is a matter for discussion.
Conclusion: The presence of even one abnormally raised feature in the fetal blood of these non-specific signs is enough to screen for a population which is of high risk for congenital toxoplasmosis and sufficient to change our attitude to treating the condition.