Acute Postviral Encephalopathy: Pathologic and Radiologic Correlation in an Atypical Case

Area of Science:

• Neurology
• Infectious Diseases
• Pathology

Background:

• Acute encephalopathy is a severe neurological complication.
• Influenza infections, particularly influenza A, have been linked to acute necrotizing encephalopathy.
• Necrotizing white matter encephalopathy presents with characteristic but sometimes variable neuropathological findings.

Purpose of the Study:

• To report a rare case of fatal acute encephalopathy following influenza infection.
• To describe the clinical, imaging, and pathological findings, highlighting atypical features.
• To discuss the potential mechanisms and differential diagnoses, including acute necrotizing encephalopathy.

Main Methods:

• Case report of an 8-year-old male with influenza infection.
• Clinical presentation including refractory seizures and hemodynamic instability.
• Magnetic resonance imaging (MRI) and post-mortem autopsy with histopathological examination.

Main Results:

• The patient developed severe neurological deterioration and hemodynamic instability post-influenza.
• MRI revealed bilateral cerebral and cerebellar white matter lesions and microhemorrhages.
• Autopsy showed extensive coagulative necrosis in the centrum semiovale and other brain regions, consistent with necrotizing white matter encephalopathy and hypoxic-ischemia.

Conclusions:

• Fatal acute encephalopathy can occur following influenza infection.
• Atypical neuropathological and imaging findings may arise due to superimposed factors like cardiovascular collapse.
• This case expands the understanding of influenza-associated encephalopathies and necrotizing white matter encephalopathy.