[The cerebral lesions in congenital toxoplasmosis. Study of 9 personal cases and 61 cases in the literature].

This study is a review of 70 cases of congenital toxoplasmosis; all of the patients were dead between birth and the age of nine. The anatomo-pathological examination of 9 personal cases (6 acute, 1 subacute, 2 chronic) is presented and compared with that of 61 cases from the literature. After a parasitological survey concerning the infectious agent, the author summarizes the macroscopic and the microscopic lesions of his personal cases. Those data are subsequently confronted to those referred to in the literature. The author makes an attempt to entangle the terminological confusion that exists between the different terms: cyst, pseudocyst, microglial nodule and granuloma. The frequency, the localization and the mechanisms of the main alterations - granuloma, necrosis, calcification, hydrocephaly - are studied as well as the vulnerability factors and the resistance of the subjects. The presence in 8 of the 9 chronic cases of calcified scar lesions in the inferior portion of the external wall of the lateral ventricles suggests a particular vulnerability of the spongioblasts in that area. In the acute cases the extensive necroses in the cerebral hemispheres seem to result from immunological reactions in an immature organism rather than from vascular thromboses that appear to be more a secondary phenomenon.