Serum ornithine carbamyl transferase activities in Reye's syndrome.

Serum levels of ornithine carbamyl transferase (S-OCT), glutamic oxaloacetic transaminase and glutamic pyruvic transaminase were compared for 37 Reye's syndrome patients with regard to variation with clinical stage an serum ammonia levels. In stage I patients, the mean S-OCT activities were greater and the serum ammonia levels lower than found with patients in the more advanced stages. Covariation of these two parameters was found only in the more advanced stages. No significant correlation with stage or serum ammonia levels was found for S-GOT or S-GPT activities. These observations are discussed in terms of their relevance to reports of an early transient decrease of hepatic OCT activity in Reye's syndrome.

Serum enzyme alterations in arginine-deficient, influenza-infected ferrets: a potential animal model of Reye's syndrome.

Young male ferrets developed hyperammonemia and encephalopathy soon after eating a diet lacking arginine. Because of this characteristic and their known susceptibility to influenza infections, they were further tested as an animal model for Reye's syndrome (RS), a childhood disorder which sometimes develops following influenza and which is characterized in part by encephalopathy, hyperammonemia, and elevated serum transaminase levels. Either the deficiency or infection alone resulted in minor elevations of serum ornithine carbamyl transferase (S-OCT) activities and together resulted in substantial elevations. These and associated alterations are discussed in relationship to the metabolic disorders occurring in RS.

Mortality due to Reye's syndrome in Michigan: distribution and longitudinal trends.

Death rates due to Reye's syndrome and related diseases among children in Michigan were estimated from 1969 to mid-1977 on the basis of searches of death certificates, with verification of diagnosis by review of hospital records. There was no significant increase in mortality for Reye's syndrome during the study period. Temporal association with type A and B influenza outbreaks was found. The syndrome occurred at a lower rate in summer and autumn when these infections, as well as chickenpox, were rare. The mean age of children dying of Reye's syndrome and related diseases was 5.5 years, with a modal age of less than one year. Deaths among white children were more frequent than among black children, but below the age of one year the reverse was true. In black children a higher mortality was found among males than among females. Deaths due to Reye's syndrome were more common in rural areas than in urban areas.

Congenital tuberculosis and associated hypoadrenocorticism.

Two cases of probable congenital tuberculosis occurring in the ten-year period from 1966 to 1976 are reported. One infant with confirmed congenital tuberculosis also had symptomatic hypoadrenocorticism. Tuberculosis should be considered in the differential diagnosis of the seriously ill infant.

Reye syndrome associated with vaccination with live virus vaccines. An exploration of possible etiologic relationships.

To determine whether vaccination with live virus vaccines may be etiologically related to Reye syndrome, we examined 404 cases reported to the Center for Disease Control. Fifteen of 269 children with Reye syndrome has been inoculated with live virus vaccines within 30 days before onset of illness. Although this temporal relationship may have occurred by chance, seasonal distribution and clustering of incubation periods suggests that live virus vaccines may occasionally serve as cofactors in the etiology of Reye syndrome through undefined mechanisms.

Possible pathogenic role of endotoxin in Reye's syndrome.

Evidence of circulating endotoxin was sought in children with Reye's syndrome, on the thesis that severe hepatic failure is likely to result in loss of capacity to detoxify intestinal endotoxins entering the circulation. A modification of the Limulus assay was used to demonstrate high levels of endotoxin-like activity (E.L.A.) in nine comatose patients with Reye's syndrome and in one of the two non-comatose patients. The symptom-free sibling of one patient had raised liver enzymes and a negative Limulus test. Plasma E.L.A. correlated significantly with degree of electroencephalographic disturbance early in the course of the illness. E.L.A. was also found in both of two cerebrospinal fluids evaluated. Preliminary in-vitro characterisation of this substance indicated that it resembled endotoxin derived from anaerobic intestinal bacteria. Intestinally derived endotoxin could be one factor in the pathogenesis of encephalopathy and other features of Reye's syndrome.