Acute viral encephalitis syndrome in paediatric patients: Clinical profile and laboratory correlation

Objectives: Acute encephalitis syndrome (AES) poses a significant public health challenge in India, particularly in children. The aetiological spectrum varies regionally, with viral agents being predominant. This study evaluates the clinico-virological profile of AES in children at a tertiary care centre in North Karnataka. Material and Methods: A prospective observational study was conducted among children aged 6 months to 12 years presenting with AES, defined as acute fever with altered sensorium and/or seizures. Detailed clinical evaluation, neuroimaging and laboratory investigations were performed. Immunoglobulin M enzyme-linked immunosorbent assay testing for herpes simplex virus type (HSV)-1, HSV-2, mumps, dengue, chikungunya and Japanese encephalitis (JE) virus was used to determine viral aetiology. Outcomes were assessed at discharge. Results: Among 41 children, 58.5% were male and most were from low socioeconomic backgrounds. Fever and altered sensorium were present in all cases; seizures occurred in 68.3%. Mumps (22%), HSV-1/2 (17%), dengue (14.6%) and JE (4.9%) were the major viral causes identified, while no aetiology could be determined in 51.2% of cases. Neuroimaging was abnormal in 34.2%, and hypoxia, low Glasgow Coma Scale and need for ventilation were associated with poorer outcomes. The mortality rate was 17%. Conclusion: A substantial proportion of AES cases remained aetiologically undiagnosed, underscoring the limitations of current diagnostic tools. Regional epidemiological data and enhanced viral testing are essential for developing targeted public health strategies, improving early detection and preventing long-term morbidity and mortality among affected children.