Background: Influenza is a common contagious respiratory virus that primarily causes respiratory tract infections. Neurological complications associated with influenza have also been reported, mainly in pediatric populations, and may be fatal.

Methods: A descriptive study evaluated pediatric patients who were diagnosed with severe influenza-associated neurological complications at the Tropical Pediatrics Center-Vietnam National Children´s Hospital from October 2022 to February 2024.

Results: In this study involving 20 patients, 80% of children were under 5 years old; 70% of patients had a history of good health. All patients had not received an influenza vaccination within 12 months. The median time from onset to neurological symptoms was 1 day. The most common neurological complication was encephalitis (16/20 patients) with symptoms included altered consciousness and seizures. Most patients had elevated levels of ALT (60%), AST (90%), LDH (94%), and ferritin (69%) in serum. The imaging of brain damage on MRI and CT scans varied in patterns and locations. There was no difference in the timing of methylprednisolone treatment within and after 48 h. The mortality rate was 20%, with 45% of patients experiencing severe sequelae.

Conclusions: IANCs are severe with damage to both white matter and central gray matter and can occur in healthy children, emphasizing the importance of vaccination to reduce the risk.