Multinucleated giant cells in areas of the brain stem necrosis after cardiac arrest in two infants.

A rare type of cellular reaction in the brain stem of two infants with cardiac arrest encephalopathy is presented. After cardiac arrest both newborns were resuscitated and put on artificial ventilation. Their survival time amounted to 16 and 18 days, respectively, in a deep coma with areflexia. At the postmortem examination a widespread hemispheric necrosis of the gray and white matter was observed as well as symmetrical necrosis of the tegmental part of the brain stem extending from the midbrain up to medulla. Striking proliferation of blood vessels and large number of multinucleated giant cells originating from monocyte/macrophage lineage was found in the areas of the brain stem necrosis. No evidence of inflammatory process was found. It seems that giant cells appeared as local reaction on disintegration of maturing structures.