Final answer:
Reye's syndrome is associated with encephalopathy, which includes swelling of the liver and brain, leading to possible neurological damage. It often follows a viral infection and can be exacerbated by the use of aspirin in children.
Step-by-step explanation:
A major symptom associated with Reye's syndrome is encephalopathy, which is swelling in the liver and brain that can lead to neurological damage. The condition often develops in children and teenagers after a viral infection, such as influenza or chickenpox. It has been specifically associated with the use of aspirin during a viral infection, which can exacerbate brain swelling and may be fatal. Therefore, it is advised to avoid using aspirin or aspirin-containing products in children younger than 19 years old when they are ill with a viral infection.