There are no official guidelines to assist in answering this question. I will search for relevant research papers instead.
From the Research
Definition and Characteristics of Reye's Syndrome
- Reye's syndrome is a serious, acute encephalopathy that has been linked with aspirin use in children and teenagers under 18 years of age 1.
- It is an acute metabolic encephalopathy, largely affecting children and adolescents, and can be characterized by a generalized disturbance in mitochondrial metabolism, eventually resulting in metabolic failure in the liver and other tissues 2.
- The disease typically is preceded by a viral infection with an intermediate disease-free interval of 3-5 days 2.
Relationship with Aspirin
- There is evidence to suggest a close link between Reye's syndrome and ingestion of aspirin during the febrile prodrome, with the drug appearing to act as a co-factor in susceptible individuals 1.
- However, the suggestion of a defined cause-effect relationship between aspirin intake and Reye syndrome in children is not supported by sufficient facts 2.
- The decline in case numbers of Reye's syndrome has been significant since government health warnings were appended to aspirin-containing formulations, and the use of aspirin in the pediatric age group has decreased 1, 3, 4.
Reye-like Syndrome
- Reye-like syndrome can result from inborn errors of metabolism, such as medium-chain acyl coenzyme A dehydrogenase deficiency, and can present with similar symptoms to Reye's syndrome 5, 3.
- Diagnostic differentiation between Reye's syndrome and Reye-like syndrome is difficult because the end results of mitochondrial dysfunction in both conditions may be similar 5, 3.