Reye's syndrome

Reye's syndrome is a rare but severe condition characterized by acute encephalopathy and fatty degeneration of the liver, typically occurring in children recovering from a viral infection, most commonly influenza or varicella, and often associated with aspirin use. It leads to rapid development of brain swelling and liver dysfunction, which can be life-threatening.

This code is used when documentation clearly indicates a diagnosis of Reye's syndrome. It is typically supported by clinical findings of acute encephalopathy, liver dysfunction (e.g., elevated liver enzymes, hyperammonemia), and a history of a preceding viral illness, often with aspirin exposure.

• Ensure documentation specifies "Reye's syndrome" and not just encephalopathy or liver failure, as these are symptoms.
• Investigate for a history of viral illness and aspirin use if not explicitly stated, as these are key diagnostic indicators.
• Code any associated viral infection (e.g., influenza, varicella) as an additional diagnosis, if present and documented.