Child Neurology: Remarkable Recovery From Severe Acute Necrotizing Encephalopathy

A previously healthy 6-year-old girl presented with several days of fever before a generalized seizure. Laboratory investigation revealed elevated liver enzymes, normal ammonia, and positive influenza A through respiratory PCR. Brain MRI demonstrated extensive, bilateral lesions in the cerebral and cerebellar white matter, thalami, basal ganglia, and brainstem. She was diagnosed with acute necrotizing encephalopathy, a rare parainfectious encephalitis commonly associated with influenza. Genetic variants have been implicated (e.g., <i>RANBP2</i> and <i>RNH1</i>), but our patient's rapid genome was nondiagnostic. Her 1-month hospitalization was complicated by prolonged encephalopathy and intracranial pressure crises requiring hyperosmolar therapy, sedation, intermittent paralysis, and hypothermia. Concomitantly, she received pulse corticosteroids, plasmapheresis, and oseltamivir. Three months after illness onset, she achieved a remarkable recovery with a normal neurologic examination. Although prognosis may comprise considerable morbidity and mortality, prompt recognition, immunotherapy, and intensive care can achieve positive neurodevelopmental outcomes. Our discussion concludes with a focus on the intrinsic uncertainties of neuroprognostication in the pediatric intensive care unit.