Inflammatory and reparative tissue reaction in developing human central nervous system.

Morphologic features of inflammatory reactions in the immature central nervous system (CNS) develop in the second half of pregnancy. The cells composing the infiltrations arise early during development but their presence in circulation and final localization in fully mature inflammatory reactions is prolonged in time. The aim of this work was to compare the picture of inflammatory infiltrations in a group of fetal brains following various infections and aseptic injuries. It was found that numerous granulocytes appeared in bacterial infections, but not in aseptic lesions of the brain. The young maturing blood cells and granulocytes demonstrate the subsequent stages in the development of the inflammatory reaction. The changes depend on the character of the injurious factor and the level of maturation of the CNS. The topography of maturing brain lesions due to infections and anoxic/ischemic damage was similar and localized most often in the periventricular white matter.