Acute necrotizing hemorrhagic encephalopathy, unspecified

This code signifies a severe, rapidly progressive inflammatory encephalopathy characterized by widespread necrosis and hemorrhage within the brain. It is a rare and often fatal condition, typically occurring in children following an acute febrile illness, and involves extensive white matter damage.

Assign this code when documentation explicitly states a diagnosis of acute necrotizing hemorrhagic encephalopathy without further specification of its underlying cause. This diagnosis is usually made based on clinical presentation, neuroimaging (e.g., MRI showing multifocal lesions with hemorrhage), and sometimes brain biopsy findings.

• Ensure documentation clearly distinguishes this from other forms of acute encephalopathy or encephalitis.
• Do not use if a more specific type of necrotizing encephalopathy (e.g., due to a specific infection) is identified.
• Code any associated infectious agent or underlying condition as a secondary diagnosis, if known.