What physiological change is associated with Reye's syndrome?

Reye's syndrome is characterized by a combination of symptoms that typically develop after a viral infection, most commonly influenza or varicella (chickenpox), particularly in children. A hallmark of this condition is the presence of fatty changes in the liver, which occurs due to the direct effect of the illness on hepatic metabolism. The accumulation of fat within liver cells leads to hepatomegaly and can result in liver failure if the syndrome progresses.

In Reye's syndrome, the exact mechanism is still not entirely understood, but it is thought to involve mitochondrial dysfunction that disrupts normal fatty acid metabolism, causing an abnormal buildup of fat in the liver. This is why identifying fatty changes in the liver is a critical aspect of diagnosing Reye's syndrome.

In considering other options, although increased intracranial pressure, altered glucose metabolism, and dehydration may be associated with various critical illnesses or complications in pediatric patients, they do not specifically encapsulate the key pathological features of Reye's syndrome. The fatty liver changes remain the defining aspect of the syndrome.