Neuropathologic findings in Reye syndrome.

Brain tissue from three patients with a clinical diagnosis of Reye syndrome was compared with tissue from three control patients. All Reye syndrome patients demonstrated cytotoxic cerebral edema, with swelling of astrocyte foot processes, which was not seen in controls. Myelin sheath splitting was seen both in controls and patients, but myelin blebs were uncommon in both. Mitochondrial changes also were not seen. Although cerebral edema is a nonspecific finding, it appears to be characteristic of Reye syndrome.