The metabolic course of Reye's syndrome: distinction between survivors and nonsurvivors.

We compared the levels of hormones and metabolites in the plasma of 37 survivors of Reye's syndrome with the levels in 8 fatal cases, at four time periods within 72 hours of admission. The most prominent differences were found for norepinephrine (NE), which was significantly elevated in fatal cases compared with survivors at all periods. Lactate and dopamine were elevated in the earlier periods. Epinephrine and alpha-amino acid nitrogen were also elevated in fatal cases, but the differences usually were not significant. NE elevation may reflect an increased sympathoadrenal medullary output associated with brain edema, compounded by impaired hepatic clearance of monoamines. Skeletal muscle ischemia from NE-induced vasoconstriction may explain the association between lactic acidemia and the severity of encephalopathy.