Biochemical abnormalities in Reye's syndrome.

Reye’s syndrome has been characterized by cerebral edema without inflam­ matory cell infiltration or demyelination, and fatty degeneration of the viscera, especially the liver.19 Serum from nine children (ages 7 months to 8 years) with Reye’s syndrome confirmed at autopsy were examined prior to death. From our chemical studies this entity is defined biochemically as a severe metabolic acidosis presenting with decreased glucose concentrations in blood and cerebrospinal fluid, high concentrations of serum uric acid, urea nitrogen, ammonia and associated with marked increase of aspartate and alanine amino­ transferase, lactic dehydrogenase and creatine phosphokinase (C P K ). Biochemically, these changes may be explained by a sudden insult to intra­ cellular respiration causing an increased tissue catabolism resulting in an elevated endogenous nitrogen load. Elevations of CPK in all subjects studied implies a severe impairment of oxidative metabolism. Since CPK isoenzymes in two patients showed marked elevations in skeletal muscle CPK ( M M ) and minor increases in heart ( M B) CPK, it may be postulated that this is a result of the primary hypoxemia and hypocapnia which these children exhibit. Serum gamma-glutamyl transpeptidase activity and bilirubin concentrations in the same patients were not increased and it is possible that liver damage in Reye’s syndrome is not so important a factor as has been reported.22 A point under study at this time is the relationship of the increased CPK con­ centration and the time of demise. Preliminary findings indicate a progressive rise in CPK suggests a grave prognosis.